WO2015074127A1 - Hydrogen production method and catalyst - Google Patents

Hydrogen production method and catalyst Download PDF

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Publication number
WO2015074127A1
WO2015074127A1 PCT/BR2013/000504 BR2013000504W WO2015074127A1 WO 2015074127 A1 WO2015074127 A1 WO 2015074127A1 BR 2013000504 W BR2013000504 W BR 2013000504W WO 2015074127 A1 WO2015074127 A1 WO 2015074127A1
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Prior art keywords
catalyst
ammonia
hydrogen
alumina
stream
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PCT/BR2013/000504
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French (fr)
Portuguese (pt)
Inventor
Roberto Carlos PONTES BITTENCOURT
Luiz Eduardo MAGALHÃES CORREA DA SILVA
Maira ANDRADE RODRIGUES
Cecilia PEREIRA RODRIGUES
Carlos Otavio BRITO
Fernanda DE CARVALHO MUNIZ BOMBARDELLI
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Petróleo Brasileiro S.A.-Petrobras
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Priority to BR112014017691-4A priority Critical patent/BR112014017691B1/en
Priority to PCT/BR2013/000504 priority patent/WO2015074127A1/en
Priority to ARP140104179A priority patent/AR098331A1/en
Publication of WO2015074127A1 publication Critical patent/WO2015074127A1/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02Impregnation, coating or precipitation
    • B01J37/0201Impregnation
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002Mixed oxides other than spinels, e.g. perovskite
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/78Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with alkali- or alkaline earth metals
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/80Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with zinc, cadmium or mercury
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/16Reducing
    • B01J37/18Reducing with gases containing free hydrogen
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B3/00Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
    • C01B3/02Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
    • C01B3/04Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by decomposition of inorganic compounds, e.g. ammonia
    • C01B3/047Decomposition of ammonia
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00Constitutive chemical elements of heterogeneous catalysts
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30Hydrogen technology
    • Y02E60/36Hydrogen production from non-carbon containing sources, e.g. by water electrolysis

Definitions

  • the present invention finds its field of application among the processes for the production of hydrogen by catalytic decomposition of ammonia solutions. More specifically, the catalytic production of hydrogen from ammoniacal gaseous streams generated in the acid water unit resulting from hydrocarbon hydrotreating processes.
  • Petroleum is composed of a complex mixture of hydrocarbons, associated with varying contents of organic compounds containing nitrogen, sulfur and oxygen and smaller amounts of metals such as vanadium, nickel, sodium, calcium and copper.
  • Oil processing generates numerous derivatives, including gasoline, diesel and aviation kerosene.
  • hydrotreating a treatment that alters or remove the impurities present in these derivatives by the use of hydrogenation reactions.
  • H 2 S hydrogen sulfide
  • NH 3 ammonia
  • the acid water stream contains contaminants that make it impossible to release it directly into the environment or reuse it in refining processes. For this to occur, it is usual for this effluent to be treated in a specific unit called the "acid water unit" for the removal of hydrogen sulfide and ammonia.
  • This effluent is treated in a specific unit called the "acid water unit" for the removal of hydrogen sulfide and ammonia.
  • the acid water stream is rectified, and gaseous streams containing ammonia and hydrogen sulfide are generated.
  • the Claus process is the standard method for eliminating sulfur from gaseous effluents. It comprises a first thermal (or combustion) step and a second catalytic (or catalytic bed) step.
  • sulfur oxide (SO 2 ) reacts with the remaining hydrogen sulfide, represented by the following reaction:
  • the sulfur thus recovered is sold in liquid or solid state.
  • Injection of the ammoniacal gas stream recovered from the acid water unit into a Claus unit may be a convenient method of disposing of this effluent.
  • it does produce some obstacles, such as the difficulty in controlling the ratio of sulfur dioxide and hydrogen sulfide concentrations in the combustion section, particularly when the ammonia stream contains hydrocarbons. This ratio is a critical factor for the correct operation of the unit.
  • carbon dioxide (C0 2) formed in combustion of hydrocarbons or previously existing in the ammonia stream lead to loss of sulfur recovery efficiency.
  • Ammonia that is not incinerated has the potential to form exit deposits in equipment such as ammonium sulfides, compromising the efficiency or campaign time of the unit.
  • partial incineration can generate a high emission of environmentally harmful nitrogen oxides (NO x ) subject to restrictions under environmental legislation.
  • NO x environmentally harmful nitrogen oxides
  • Some oils occurring in Brazil are characterized by high levels of nitrogenous compounds, for example, the one exploited in the Campos Basin. As a consequence, the acid water unit produces a lift gas with ammonia content lift.
  • Ammonia can be recovered directly in anhydrous form or in aqueous solution, or indirectly in the form of sodium hydrosulfide, ammonium thiosulfate, ammonium sulfate and ammonium phosphate.
  • Nickel-based catalysts are used in refractory supports of alpha-alumina, magnesium aluminates and calcium aluminates.
  • hydrocarbons used in addition to natural gas and naphtha are refinery gases, propane and butanes.
  • propane and butanes are refinery gases, propane and butanes.
  • the steam reforming process is usually conducted by introducing a previously purified charge into a variable number of fixed bed reactors.
  • Such reactors are constructed of metal tubes, typically 7 cm to 15 cm in diameter and 10 m to 13 m high, located inside a heating furnace that supplies the heat needed for the reactions.
  • the reactor and furnace assembly is called the primary reformer.
  • the typical inlet temperature of the gases to be processed in the primary reformer reactors is in the range of 400 ° C to 550 ° C, and the outlet temperature in the range of 750 ° C to 950 ° C at typical pressures in the range. from 10 kgf / cm 2 to 35 kgf / cm 2 .
  • ammonia decomposition reaction thermodynamically favored by the use of high temperatures, is represented by the equation:
  • thermodynamic equilibrium predicts a conversion greater than 99.5%.
  • Decomposition of ammonia into hydrogen and nitrogen can be performed on a variety of catalysts, such as those based on platinum (Pt), rhodium (Rh), palladium (Pd), iridium (Ir) and nickel (Ni). It is known and used in industrial practice that decomposition of ammonia can be performed by nickel-based catalysts under the conditions of the primary reformer. Such decomposition can be used for the initial reduction of catalysts supplied as nickel oxide, according to the equations below:
  • Nickel-based catalysts used in the primary reformer are highly susceptible to poisoning deactivation. Most common contaminants are sulfur, arsenic, phosphorus, lead and halogens. These should be reduced to levels below 0.1 ppm, preferably below 0.01 ppm to achieve adequate catalytic activity and therefore a campaign time of at least 3 years.
  • the aqueous stream that is treated in the acid water unit contains hydrogen sulfide and ammonia in contents ranging from 300 ppm to 20,000 ppm, with ammonia to hydrogen sulfide ratios in the range 1 to 2.0.
  • This stream may further contain other contaminants such as hydrocarbons, chlorides, sulfates, formates, cyanides, cations such as sodium, potassium and calcium, mineral or organic acids and dissolved gases such as carbon dioxide and oxygen in varying concentrations.
  • US 2007/0178034 discloses a process for removing organic and inorganic sulfur compounds from an ammonia stream.
  • Sulfur is removed by a catalytic absorbent fixed bed composed of a catalyst with nickel mass ranging from 10% to 30%.
  • the catalyst support is chosen from alumina, silica, titania, magnesium, zirconia or a mixture thereof.
  • the promoter is chosen from the oxides of the chemical elements cerium, praseodymium, neodymium, promethium, samarium or a mixture thereof. Methanation catalysts are indicated as preferred.
  • the ammoniacal current after The sulfur removal is mixed with a hydrocarbon stream and is employed for hydrogen generation in a steam reforming process.
  • the purification method presented herein is specific for the removal of sulfur compounds.
  • An ammoniacal current generated in an "acid water" unit contains a plurality of other contaminants.
  • EP 0096970 discloses a process for removing organic sulfur compounds such as hydrogen sulfide, mercaptans, sulfides and disulfides present in ammonia streams generated in the processing of hydrocarbons, oil shale and coal. Sulfur is removed in a zinc oxide bed at a reaction temperature in the range of 260 ° C to 454 ° C. However, no mention is made of the purification of other contaminants or of their use for hydrogen production.
  • US 7,258,848 discloses a process for treating gases containing ammonia and hydrogen sulfide.
  • Ammonia is removed by washing the gases with a strong acid, for example concentrated sulfuric acid, to convert the ammonia to a salt.
  • a strong acid for example concentrated sulfuric acid
  • the aqueous solution or crystallized ammonia salt may be employed as fertilizer.
  • the purification processes of ammonia currents generated in acid water units are specific for the removal of sulfur compounds.
  • the prior art lacks a process that removes other contaminants, such as halogen compounds, metals and hydrocarbons, and results in an ammoniacal current which, employed in a catalytic reforming process for hydrogen production, leads to a reduced rate. of catalyst deactivation.
  • the object of the present invention is a process for the production of hydrogen by catalytic decomposition of ammonia solutions. from acid water units.
  • Such a process involves the purification of an ammonia stream and the use of this purified stream as a charge in a steam reforming process.
  • the purification step removes impurities such as sulfur, halogens, metals and olefin hydrocarbons.
  • the purified stream is fed to a reforming furnace, which is part of the steam reforming process, for the conversion of ammonia to hydrogen.
  • a catalyst is synthesized, whose characteristics make it possible to use it to purify the ammonia current with a low deactivation rate.
  • the present invention relates to a process for producing hydrogen by catalytic decomposition of ammonia solutions from acidic water units.
  • the objective is achieved by a process carried out in two main steps, namely: a first ammonia current purification step comprising a pretreatment of the ammonia current in a plurality of catalyst beds, and a second step, which consists in the submission of the treated current to the steam reform.
  • a catalyst is synthesized, the characteristics of which enable its use in the purification step of the ammoniacal current.
  • the invention is a continuous process for the production of hydrogen, carried out in two steps:
  • the first step comprises the following steps:
  • the second step comprises the following steps:
  • the present invention can be applied to existing hydrogen production units by the steam reforming process by simply adapting the pretreatment section of the existing unit to the plurality of beds.
  • a hydrocarbon stream can also be fed in the first process step.
  • the hydrocarbon stream corresponds to the charge that is normally employed in industrial hydrogen production units by the steam reforming process.
  • the ammoniacal current corresponds to a fraction of the hydrocarbon charge and is in the range of 1% to 10% by volume.
  • Hydrocarbons may be chosen from natural gas, liquefied petroleum gas, naphtha and a mixture thereof in any proportion.
  • hydrogen is preferably added to the filler to prevent coke formation in the second catalytic bed.
  • the inclusion of nickel oxide in the catalyst formulation enables the partial transformation of ammonia to hydrogen and nitrogen.
  • the catalyst is synthesized containing nickel oxide as the active phase, supported by materials chosen from zinc oxide, alumina and a mixture thereof, and promoted by materials chosen from alkaline and alkaline earth metals.
  • the catalyst is obtained by dry impregnation technique from the impregnation of a support selected from alumina and zinc oxide with a metal hydroxide solution to obtain a material of type K / alumina or K / ZnO. .
  • the material is dry and calcined.
  • the calcined material is then impregnated with nickel nitrate solution, dried and calcined again, giving rise to the catalyst whose characteristics allow its use for the purification of the ammonia current with a low deactivation rate.
  • Catalyst synthesis will be presented in detail below.
  • the fourth bed is composed of materials that can be chosen from zinc and copper oxides in contents above 50% by mass.
  • materials that can be chosen from zinc and copper oxides in contents above 50% by mass.
  • LTS low temperature shift
  • the beds used in the first stage are mounted inside reactors.
  • Each reactor contains a single bed type, totaling four beds and four different reactors.
  • the plurality of beds may be contained in a single reactor.
  • the arrangement of beds in a single or several reactors is determined by the volumetric capacity of the unit and the relative costs of the equipment.
  • the volume of each bed should be selected according to the content of contaminants present in the ammonia stream, as well as the campaign time projected for an industrial unit.
  • the use of the first and second beds in an industrial configuration of the present invention is determined by the type of contaminants present. Thus, in a metal free load, the use of the first bed is not necessary. In a load free of organic sulfur, the use of the second bed is not necessary.
  • the use of the fourth bed for the final removal of inorganic and organic compounds containing sulfur and chlorides is determined by the contaminant content allowed in the product, as well as the objective campaign time of the reformer of an industrial unit.
  • purified ammonia current is routed to a pre-reformer, and, alternatively, to a primary reformer, commonly employed in the steam reform process.
  • a primary reformer commonly employed in the steam reform process.
  • the residual ammonia from the third bed is converted into hydrogen and nitrogen.
  • the stream obtained after the conversion reaction shall be treated to remove impurities mixed with hydrogen.
  • the treatment methods employed are known from the state of the art.
  • the reduction of carbon monoxide (CO) content occurs by the displacement reaction.
  • the removal of carbon monoxide, carbon dioxide, methane and nitrogen occurs by the use of a pressure variation adsorption system (PSA).
  • PSA pressure variation adsorption system
  • the catalyst developed according to the present invention is employed in the third bed being capable of decomposing ammonia and simultaneously removing chloride (Cl) and sulfur (S) from the ammonia stream.
  • the catalyst can be chosen from an alumina supported catalyst, promoted by an alkaline or alkaline earth metal, preferably potassium, and with an active phase of nickel oxide (NiO / K / alumina) and a zinc oxide supported catalyst by an alkaline or alkaline earth metal, preferably potassium, and with an active nickel oxide phase (NiO / K / ZnO).
  • alumina and zinc oxide silica alumina or mixtures thereof may be used as a support.
  • the alkali metal content employed in the catalyst is in the range 1% to 7% by weight, preferably 2% to 4% by weight.
  • the nickel oxide content employed in the catalyst is in the range of 5% to 40% by weight, preferably between 10% to 20% by weight.
  • Catalysts with specific area in the range of 15 m 2 / g to 30 m 2 / g are obtained.
  • EXAMPLE 1 Synthesis of NiO / K / alumina catalyst.
  • alumina-supported catalyst was synthesized, promoted by potassium and active phase of nickel oxide (NiO / K / alumina).
  • the catalyst was prepared with two hundred grams of Pural SB alumina hydroxide (Condea Chemie), impregnated with an aqueous solution of 11.5 grams of potassium hydroxide (KOH) by the dry impregnation technique (pore volume technique).
  • KOH potassium hydroxide
  • the material thus obtained was dried at temperatures in the range of 100 ° C to 120 ° C for a period of time in the range of 8 hours to 12 hours and calcined at temperature around 600 ° C for a period of time around 4 ° C. hours After this time, the calcination temperature was raised to around 1,200 ° C for a time of about 1 hour to obtain a K / alumina type material.
  • K / alumina material was impregnated with an aqueous solution containing 27.2 grams of nickel nitrate hexahydrate [Ni (N03) 2.6H20] by dry impregnation technique (pore volume technique). followed by drying at a temperature in the range of 100 ° C to 120 ° C for a period of time in the range of 8 hours to 12 hours and calcined at a temperature of around 450 ° C for a period of about 4 hours to obtain a NiO / K / alumina catalyst.
  • the catalyst thus obtained had a concentration of 3% by weight of potassium (K), 15% by weight of nickel oxide (NiO) and a specific area of 27,7 m 2 / g determined by the nitrogen adsorption technique.
  • the catalyst is employed for ammonia conversion and removal of chloride and sulfur.
  • EXAMPLE 2 Synthesis of NiO / K / ZnO Catalyst.
  • the potassium-promoted zinc oxide support catalyst and nickel oxide active phase (NiO / K / ZnO) were synthesized.
  • the catalyst was prepared with one hundred and fifty grams of a commercial zinc oxide impregnated with an aqueous solution of 3.01 grams of potassium hydroxide (KOH) by pore volume technique.
  • KOH potassium hydroxide
  • the material thus obtained was dried at a temperature of about 110 ° C and calcined at a temperature of about 450 ° C for a period of about 4 hours to obtain a K / ZnO type material.
  • Ni (NO3) 2.6H20 nickel nitrate hexahydrate
  • the catalyst thus obtained had a concentration of 2% by weight of potassium (K) and 15% by weight of nickel oxide (NiO) and a specific area of 17,2 m 2 / g determined by the nitrogen adsorption technique.
  • the catalyst is employed for ammonia conversion and removal of chloride and sulfur.
  • a first selected catalyst is a commercial nickel-based catalyst.
  • a second catalyst selected for the low temperature shift (LTS) step in the steam reforming hydrogen production process is a commercial CuO / ZnO / AI 20 type catalyst.
  • the catalysts were initially pretreated under hydrogen flow at a temperature of 400 ° C for a period of 60 minutes and then cooled to a temperature of 350 ° C.
  • the experiment consists of passing a flow of 40 mL / min. of hydrogen in a saturator containing concentrated hydrochloric acid PA kept at a temperature of 10 ° C and feed it to the reactor.
  • the catalysts are compared over time to observe the appearance of chloride in the reactor effluent.
  • An average hydrogen chloride solution concentration of 34% was assumed (corresponding to a vapor pressure of hydrogen chloride on the solution of 26.4 mmHg according to the tabulated values in the literature).
  • the time for chloride "leakage” to occur was used to estimate chloride retention capacity (kg Cl / kg material).
  • the reactor effluent was followed by mass spectrometry, monitoring the fragment with a mass / charge ratio of 36.
  • Example 1 the material synthesized in Example 1 has a 75% higher chloride retention capacity than the commercial methanation catalyst (base case).
  • the catalyst synthesized in Example 2 has an 875% higher chloride retention capacity relative to the commercial methanation catalyst.
  • the catalysts were initially pretreated under hydrogen flow at a temperature of 400 ° C for a period of 60 minutes and then cooled to a temperature of 350 ° C.
  • Sulfur was fed to the reactor by passing an 8 ml flow per minute of a gas mixture containing 15% hydrogen sulfide in hydrogen.
  • the presence of hydrogen sulfide was detected in the reactor effluent by the use of ampoules for the detection of hydrogen sulfide, known as the Drager ampoule.
  • the catalysts are compared over time to observe the appearance of sulfur in the reactor effluent and this value used to estimate sulfur retention capacity (kg S / kg material). Results are presented in Table 2 below.
  • Example 2 According to Table 2, the material synthesized in Example 2 has 177% higher sulfur retention capacity than the commercial methanation catalyst.
  • the commercial catalyst LTS according to the process of the present invention can be used to make up the plurality of acid water stream purification beds as it has 200% superior chloride retention capacity and superior sulfur retention capacity. 205% over the methanation catalyst.
  • the catalysts were initially pretreated under hydrogen flow at 450 ° C for a time period of 60 minutes.
  • Ammonia was fed to the reactor by passing flow rates in the range of 10 mL / min. at 40 mL / min. of hydrogen in a saturator containing concentrated ammonium hydroxide PA at a concentration in the range of 28 to 30% ammonia maintained at a temperature of 10 ° C.
  • the reactor effluent was monitored by mass spectrometry, monitoring the fragments with the mass / charge ratio of 17 and 28 for ammonia and nitrogen, respectively.
  • the catalysts are compared for ammonia conversion activity (%) by varying the hourly space gas velocity (GHSV) parameter and the reaction temperature, as shown in Table 3 below.
  • GHSV hourly space gas velocity
  • Example 1 shows greater decomposition activity of ammonia in hydrogen and nitrogen than observed in the methanation catalyst. Both catalysts exhibit significant ammonia decomposition activity only at temperatures above 450 ° C.
  • the decomposition reaction of ammonia it is not necessary for the decomposition reaction of ammonia to occur simultaneously with the treatment of the stream to remove contaminants such as sulfur and chloride, as such reaction will occur downstream of the purification step in primary reform stage of the hydrogen production process by steam reforming.
  • the examples demonstrate that chloride retention can be increased by up to 875% and sulfur retention by up to 177% by using the catalysts synthesized in the present invention over commercial methanation catalysts.
  • the commercial catalyst LTS which according to the present invention can be used to make up the plurality of acid water stream purification beds has 200% higher chloride holding capacity and 205% higher sulfur holding capacity. regarding commercial methanation catalysts.

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Abstract

The present application discloses a method for producing hydrogen by catalytic decomposition of ammonia from acid water units. In a first step, the ammonia stream is purified in contact with various catalytic beds, removing chlorides and sulfur, and more specifically, ammonia is partially transformed into hydrogen in the bed formed by a catalyst based on alkalis and alkaline earths, supported on zinc oxide, alumina, silica-alumina and mixtures thereof, with nickel oxide as the active phase. In the second step, the purified ammonia stream is fed to the steam reforming reactor to generate hydrogen which is then purified. The application also relates to the catalyst used in the method.

Description

PROCESSO E CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO  Hydrogen production process and catalyst
CAMPO DA INVENÇÃO FIELD OF INVENTION
A presente invenção encontra seu campo de aplicação dentre os processos para a produção de hidrogénio por decomposição catalítica de soluções amoniacais. Mais especificamente, a produção catalítica de hidrogénio a partir de correntes gasosas amoniacais geradas na unidade de águas ácidas decorrente de processos de hidrotratamento de hidrocarbonetos. The present invention finds its field of application among the processes for the production of hydrogen by catalytic decomposition of ammonia solutions. More specifically, the catalytic production of hydrogen from ammoniacal gaseous streams generated in the acid water unit resulting from hydrocarbon hydrotreating processes.
FUNDAMENTOS DA INVENÇÃO  BACKGROUND OF THE INVENTION
O petróleo é composto por uma complexa mistura de hidrocarbonetos, associada a teores variáveis de compostos orgânicos contendo nitrogénio, enxofre e oxigénio e menores quantidades de metais, tais como: vanádio, níquel, sódio, cálcio e cobre.  Petroleum is composed of a complex mixture of hydrocarbons, associated with varying contents of organic compounds containing nitrogen, sulfur and oxygen and smaller amounts of metals such as vanadium, nickel, sodium, calcium and copper.
O processamento do petróleo gera inúmeros derivados, dentre os quais, gasolina, óleo diesel e querosene de aviação.  Oil processing generates numerous derivatives, including gasoline, diesel and aviation kerosene.
Compostos tais como enxofre, nitrogénio, oxigénio, halogênios e metais são classificados como indesejáveis nos derivados, pois ao longo da cadeia de consumo geram poluentes atmosféricos e alteram a integridade de equipamentos e do próprio derivado.  Compounds such as sulfur, nitrogen, oxygen, halogens and metals are classified as undesirable in derivatives because along the consumption chain they generate atmospheric pollutants and alter the integrity of equipment and the derivative itself.
Para garantir a qualidade e a adequação à legislação vigente, é usual encaminhar esses derivados para um tratamento denominado "hidrotratamento", cuja característica é alterar, ou remover, as impurezas presentes nestes derivados pelo emprego de reações de hidrogenação.  To ensure quality and compliance with current legislation, it is usual to refer these derivatives to a treatment called "hydrotreating", whose characteristic is to alter or remove the impurities present in these derivatives by the use of hydrogenation reactions.
Para hidrocarbonetos tendo como contaminantes enxofre e nitrogénio, reações de hidrogenação geram sulfeto de hidrogénio (H2S) e amónia (NH3). Estas reações ocorrem em reatores preenchidos com leitos fixos e que utilizam catalisadores manufaturados em sua maioria com sulfetos de níquel (ou cobalto) e molibdênio, suportados principalmente em alumina. For hydrocarbons having sulfur and nitrogen contaminants, hydrogenation reactions generate hydrogen sulfide (H 2 S) and ammonia (NH 3 ). These reactions occur in fixed bed filled reactors that use catalysts manufactured mostly from nickel (or cobalt) and molybdenum sulfides, supported mainly by alumina.
Durante o processo de hidrotratamento é realizada a injeção de água, que ocorre em etapa prévia à separação entre o hidrogénio utilizado em excesso à estequiometria das reações de hidrogenação e os produtos do processo. O objetivo da injeção de água é reter sulfeto de hidrogénio e amónia em solução aquosa. Este procedimento evita a deposição de sais, tal como o sulfeto de amónia (NH4SH), que poderiam obstruir linhas e equipamentos, após processo de deposição, se presente na corrente de hidrocarbonetos. A solução aquosa assim obtida constitui um efluente denominado "água ácida". During the hydrotreating process the injection of water, which occurs prior to the separation between the excess hydrogen used at the stoichiometry of the hydrogenation reactions and the process products. The goal of water injection is to retain hydrogen sulfide and ammonia in aqueous solution. This avoids the deposition of salts such as ammonium sulfide (NH 4 SH) which could clog lines and equipment after deposition if present in the hydrocarbon stream. The aqueous solution thus obtained constitutes an effluent called "acid water".
Além do hidrotratamento, diversos processos da indústria do refino também geram água ácida. São exemplos: a destilação, o craqueamento catalítico, o hidrocraqueamento, o craqueamento térmico e o coqueamento retardado.  In addition to hydrotreating, various processes in the refining industry also generate acidic water. Examples are distillation, catalytic cracking, hydrocracking, thermal cracking and delayed coking.
A corrente de água ácida contém contaminantes que inviabilizam a sua liberação direta no meio ambiente ou o seu reaproveitamento em processos de refino. Para que isso ocorra, é usual que este efluente sofra um tratamento em uma unidade específica denominada "unidade de águas ácidas" para a retirada do sulfeto de hidrogénio e da amónia. Múltiplas configurações de unidades de águas ácidas são encontradas na literatura técnica especializada. A corrente de água ácida é retificada, e são geradas correntes gasosas contendo amónia e sulfeto de hidrogénio.  The acid water stream contains contaminants that make it impossible to release it directly into the environment or reuse it in refining processes. For this to occur, it is usual for this effluent to be treated in a specific unit called the "acid water unit" for the removal of hydrogen sulfide and ammonia. Multiple configurations of acid water units are found in the specialized technical literature. The acid water stream is rectified, and gaseous streams containing ammonia and hydrogen sulfide are generated.
Um método rotineiramente empregado para o tratamento final destas correntes gasosas amoniacais geradas na unidade de águas ácidas é a incineração.  One method routinely employed for the final treatment of these ammoniacal gas streams generated in the acid water unit is incineration.
Na indústria de petróleo, o processo Claus é o método padrão para a eliminação do enxofre de efluentes gasosos. Compreende uma primeira etapa térmica (ou de combustão) e uma segunda etapa catalítica (ou de leitos catalíticos).  In the petroleum industry, the Claus process is the standard method for eliminating sulfur from gaseous effluents. It comprises a first thermal (or combustion) step and a second catalytic (or catalytic bed) step.
Compostos de enxofre presentes na corrente amoniacal são incinerados nos queimadores de uma unidade do processo Claus para recuperar o enxofre. As reações da etapa térmica do processo Claus são: H2S + y2 o2→ so2 + H2O Sulfur compounds present in the ammonia stream are incinerated in the burners of a Claus process unit to recover sulfur. The thermal step reactions of the Claus process are: H 2 S + y 2 o 2 → so 2 + H 2 O
2NH3 + 3/202→ N2 + H20 2NH 3 + 3/20 2 → N 2 + H 2 0
Na etapa catalítica, o óxido de enxofre (S02) reage com o remanescente de sulfeto de hidrogénio, representado pela seguinte reação: In the catalytic step, sulfur oxide (SO 2 ) reacts with the remaining hydrogen sulfide, represented by the following reaction:
2H2S + S02→ S + 2H20 2H 2 S + S0 2 → S + 2H 2 0
O enxofre assim recuperado é comercializado no estado líquido ou sólido.  The sulfur thus recovered is sold in liquid or solid state.
A injeção da corrente gasosa amoniacal, recuperada na unidade de águas ácidas, em uma unidade Claus pode ser um método conveniente de dispor deste efluente. No entanto, produz alguns obstáculos, como a dificuldade em controlar a relação das concentrações de dióxido de enxofre e sulfeto de hidrogénio na seção de combustão, particularmente, quando a corrente amoniacal contiver hidrocarbonetos. Esta relação é um fator critico para a correta operação da unidade. Adicionalmente, o dióxido de carbono (C02) formado na combustão de hidrocarbonetos ou previamente existente na corrente amoniacal, acarreta perda da eficiência de recuperação do enxofre. A amónia que não for incinerada apresenta a capacidade potencial de formar depósitos de saís nos equipamentos, tais como sulfetos de amónia, comprometendo a eficiência ou o tempo de campanha da unidade. Paralelamente, a incineração parcial pode gerar uma elevada emissão de óxidos de nitrogénio (NOx), danosos ao meio ambiente e sujeitos a restrições previstas na legislação ambiental. Injection of the ammoniacal gas stream recovered from the acid water unit into a Claus unit may be a convenient method of disposing of this effluent. However, it does produce some obstacles, such as the difficulty in controlling the ratio of sulfur dioxide and hydrogen sulfide concentrations in the combustion section, particularly when the ammonia stream contains hydrocarbons. This ratio is a critical factor for the correct operation of the unit. Additionally, carbon dioxide (C0 2) formed in combustion of hydrocarbons or previously existing in the ammonia stream, lead to loss of sulfur recovery efficiency. Ammonia that is not incinerated has the potential to form exit deposits in equipment such as ammonium sulfides, compromising the efficiency or campaign time of the unit. At the same time, partial incineration can generate a high emission of environmentally harmful nitrogen oxides (NO x ) subject to restrictions under environmental legislation.
Uma dificuldade adicional enfrentada para o uso de correntes amoniacais em unidades Claus no estado da técnica está limitado a um valor máximo de adição de amónia em relação ao total da carga processada em torno de 30% a 35% em base úmida.  An additional difficulty faced with the use of ammonia currents in Claus units in the prior art is limited to a maximum ammonia addition value relative to the total processed charge of about 30% to 35% on wet basis.
Alguns petróleos de ocorrência no Brasil caracterizam-se por altos teores de compostos nitrogenados, por exemplo, o explorado na Bacia de Campos. Em consequência, a unidade de águas ácidas produz uma corrente gasosa com elevador teor de amónia. Some oils occurring in Brazil are characterized by high levels of nitrogenous compounds, for example, the one exploited in the Campos Basin. As a consequence, the acid water unit produces a lift gas with ammonia content lift.
Uma solução técnica para contornar essa situação é a incineração combinada: utilizando-se a unidade Claus até o limite estabelecido pela técnica, e o encaminhamento do excesso de amónia para um incinerador dedicado.  One technical solution to circumvent this situation is combined incineration: using the Claus unit to the limit established by the technique, and directing excess ammonia to a dedicated incinerator.
Embora conhecido do estado da técnica, a incineração da corrente amoniacal oriunda da unidade de águas ácidas, seja em uma unidade do tipo Claus ou em um incinerador dedicado, não gera produtos que possam ser comercializados.  Although known from the state of the art, incineration of the ammonia stream from the acid water unit, either in a Claus type unit or in a dedicated incinerator, does not generate products that can be traded.
São encontrados, na literatura técnica especializada, diferentes processos para a recuperação de amónia presente em correntes de águas ácidas. A amónia pode ser recuperada diretamente na forma anidra ou em solução aquosa, ou indiretamente, na forma de hidrossulfeto de sódio, tiosulfato de amónia, sulfato de amónia e fosfato de amónia.  Different processes for the recovery of ammonia present in acidic water streams are found in the specialized technical literature. Ammonia can be recovered directly in anhydrous form or in aqueous solution, or indirectly in the form of sodium hydrosulfide, ammonium thiosulfate, ammonium sulfate and ammonium phosphate.
Assume grande importância, especificamente para a indústria do petróleo, a recuperação da amónia por meio de sua transformação em hidrogénio, pois este é um insumo utilizado em larga escala em processos de hidrotratamento. Atualmente, para a produção de hidrogénio, são empregados preferencialmente gás natural e nafta, matérias-primas de elevado custo, porém, de múltiplos usos. O primeiro, empregado na matriz energética, o segundo, matéria-prima nas centrais petroquímicas.  Of particular importance to the oil industry is the recovery of ammonia through its transformation into hydrogen, as this is a large-scale input used in hydrotreating processes. Currently, for the production of hydrogen, natural gas and naphtha are preferably used, which are high-cost but multi-purpose raw materials. The first, used in the energy matrix, the second, raw material in the petrochemical plants.
O processo mais utilizado para produzir hidrogénio em larga escala, na indústria do refino, é a reforma a vapor. Hidrocarbonetos reagem com vapor de água, em elevadas temperaturas e pressões. São empregados catalisadores a base de níquel em suportes refratários de alfa-alumina, aluminatos de magnésio e aluminatos de cálcio.  The most widely used process for producing large scale hydrogen in the refining industry is steam reforming. Hydrocarbons react with water vapor at high temperatures and pressures. Nickel-based catalysts are used in refractory supports of alpha-alumina, magnesium aluminates and calcium aluminates.
Em unidades de grande capacidade, os hidrocarbonetos utilizados além do gás natural e da nafta, são os gases de refinaria, o propano e butanos. Tendo como exemplo o metano, as principais reações são representadas pelas equações abaixo, que em conjunto, têm um saldo altamente endotérmico. In large capacity units, the hydrocarbons used in addition to natural gas and naphtha are refinery gases, propane and butanes. Taking methane as an example, the main reactions are represented by the equations below, which together have a balance highly endothermic.
CH4+ H20→ CO + 3H2 (endotérmica, 206,4 kJ/mol). CH 4 + H 2 O → CO + 3H 2 (endothermic, 206.4 kJ / mol).
CO + H20→ C02 + H2 (exotérmica, - 41 ,2kJ/mol). CO + H 2 0 → CO 2 + H 2 (exothermic, - 41.2kJ / mol).
O processo de reforma a vapor é usualmente conduzido pela introdução de uma carga previamente purificada, em um número variável de reatores de leito fixo. Tais reatores são construídos com tubos metálicos, com dimensões típicas entre 7 cm e 15 cm de diâmetro externo e altura na faixa de 10 m a 13 m, localizados no interior de um forno de aquecimento, que supre o calor necessário para as reações. O conjunto de reatores e forno é chamado de reformador primário. A temperatura típica de entrada dos gases a serem processados nos reatores do reformador primário situa-se na faixa de 400°C a 550°C, e a de saída, na faixa de 750°C a 950°C, em pressões típicas na faixa de 10 kgf/cm2 a 35 kgf/cm2. The steam reforming process is usually conducted by introducing a previously purified charge into a variable number of fixed bed reactors. Such reactors are constructed of metal tubes, typically 7 cm to 15 cm in diameter and 10 m to 13 m high, located inside a heating furnace that supplies the heat needed for the reactions. The reactor and furnace assembly is called the primary reformer. The typical inlet temperature of the gases to be processed in the primary reformer reactors is in the range of 400 ° C to 550 ° C, and the outlet temperature in the range of 750 ° C to 950 ° C at typical pressures in the range. from 10 kgf / cm 2 to 35 kgf / cm 2 .
A reação de decomposição da amónia, termodinamicamente favorecida pelo uso de elevadas temperaturas, é representada pela equação:  The ammonia decomposition reaction, thermodynamically favored by the use of high temperatures, is represented by the equation:
NH3→1,5H2 + 0,5N2 NH 3 → 1.5H 2 + 0.5N 2
Conforme a literatura técnica, sob temperaturas de reação superiores a 527°C e pressão de 1 ,9 bar, o equilíbrio termodinâmico prevê uma conversão superior a 99,5%.  According to the technical literature, under reaction temperatures above 527 ° C and a pressure of 1.9 bar, the thermodynamic equilibrium predicts a conversion greater than 99.5%.
A decomposição da amónia em hidrogénio e nitrogénio pode ser realizada sobre uma variedade de catalisadores, tais como aqueles baseados em: platina (Pt), ródio (Rh), paládio (Pd), irídio (Ir) e níquel (Ni). É conhecido e utilizado na prática industrial, que a decomposição de amónia pode ser realizada por catalisadores à base de níquel sob as condições existentes no reformador primário. Tal decomposição pode ser utilizada para a redução inicial dos catalisadores, fornecidos na forma de óxido de níquel, conforme as equações abaixo:  Decomposition of ammonia into hydrogen and nitrogen can be performed on a variety of catalysts, such as those based on platinum (Pt), rhodium (Rh), palladium (Pd), iridium (Ir) and nickel (Ni). It is known and used in industrial practice that decomposition of ammonia can be performed by nickel-based catalysts under the conditions of the primary reformer. Such decomposition can be used for the initial reduction of catalysts supplied as nickel oxide, according to the equations below:
NH3→1,5H2 + 0,5N2 NH 3 → 1.5H 2 + 0.5N 2
H2 + NiO/suporte→ Ni/suporte + H20 A literatura técnica e a prática industrial também ensinam que os catalisadores á base de níquel, utilizados no reformador primário, são altamente suscetíveis à desativação por envenenamento. Contaminantes mais comuns são: enxofre, arsénio, fósforo, chumbo e halogênios. Estes devem ser reduzidos a níveis inferiores a 0,1 ppm, preferencialmente inferiores a 0,01 ppm para alcançar uma adequada atividade catalítica e, consequentemente, um tempo de campanha de pelo menos 3 anos. H 2 + NiO / holder → Ni / holder + H 2 0 Technical literature and industry practice also teach that nickel-based catalysts used in the primary reformer are highly susceptible to poisoning deactivation. Most common contaminants are sulfur, arsenic, phosphorus, lead and halogens. These should be reduced to levels below 0.1 ppm, preferably below 0.01 ppm to achieve adequate catalytic activity and therefore a campaign time of at least 3 years.
A corrente aquosa que é tratada na unidade de águas ácidas contém sulfeto de hidrogénio e amónia em teores na faixa de 300 ppm a 20.000 ppm, com relações amónia para sulfeto de hidrogénio na faixa de 1 a 2,0. Esta corrente pode ainda conter outros contaminantes, tais como hidrocarbonetos, cloretos, sulfatos, formatos, cianetos, cátions como sódio, potássio e cálcio, ácidos minerais ou orgânicos e gases dissolvidos como dióxido de carbono e oxigénio em concentrações variadas.  The aqueous stream that is treated in the acid water unit contains hydrogen sulfide and ammonia in contents ranging from 300 ppm to 20,000 ppm, with ammonia to hydrogen sulfide ratios in the range 1 to 2.0. This stream may further contain other contaminants such as hydrocarbons, chlorides, sulfates, formates, cyanides, cations such as sodium, potassium and calcium, mineral or organic acids and dissolved gases such as carbon dioxide and oxygen in varying concentrations.
A corrente gasosa que é gerada na unidade de águas ácidas, além da contaminação por compostos de enxofre, como sulfeto de hidrogénio e mercaptanas, apresenta ainda outros contaminantes, por vezes abaixo dos limites de detecção analíticos, mas suficientes para causar a desativação dos catalisadores de reforma primária. Potenciais contaminantes são os compostos inorgânicos e orgânicos de cloro. Cloretos podem reduzir significativamente a atividade de catalisadores de reforma a vapor.  The gaseous stream that is generated in the acid water unit, in addition to contamination by sulfur compounds such as hydrogen sulfide and mercaptans, also has other contaminants, sometimes below analytical detection limits, but sufficient to cause deactivation of sulfur catalysts. primary reform. Potential contaminants are inorganic and organic chlorine compounds. Chlorides can significantly reduce the activity of steam reforming catalysts.
O documento US 2007/0178034 apresenta um processo para a remoção de compostos orgânicos e inorgânicos de enxofre de uma corrente amoniacal. O enxofre é removido por um leito fixo absorvente catalítico composto por um catalisador com a massa de níquel variando entre 10% e 30%. O suporte do catalisador é escolhido entre alumina, sílica, titânia, magnésio, zircônia ou uma mistura destes. O promotor é escolhido entre os óxidos dos elementos químicos cério, praseodímio, neodímio, promécio, samário ou uma mistura destes. Os catalisadores de metanação são indicados como os preferidos. A corrente amoniacal, após a retirada do enxofre, é misturada a uma corrente de hidrocarbonetos e é empregada para a geração de hidrogénio em um processo de reforma a vapor. O método de purificação apresentado neste documento é específico para a remoção de compostos de enxofre. Uma corrente amoniacal, gerada em uma unidade de "águas ácidas", contem uma pluralidade de outros contaminantes. US 2007/0178034 discloses a process for removing organic and inorganic sulfur compounds from an ammonia stream. Sulfur is removed by a catalytic absorbent fixed bed composed of a catalyst with nickel mass ranging from 10% to 30%. The catalyst support is chosen from alumina, silica, titania, magnesium, zirconia or a mixture thereof. The promoter is chosen from the oxides of the chemical elements cerium, praseodymium, neodymium, promethium, samarium or a mixture thereof. Methanation catalysts are indicated as preferred. The ammoniacal current after The sulfur removal is mixed with a hydrocarbon stream and is employed for hydrogen generation in a steam reforming process. The purification method presented herein is specific for the removal of sulfur compounds. An ammoniacal current generated in an "acid water" unit contains a plurality of other contaminants.
O documento EP 0096970 apresenta um processo para remoção de compostos orgânicos de enxofre tais como sulfeto de hidrogénio, mercaptanas, sulfetos e dissulfetos presentes em correntes amoniacais geradas no processamento de hidrocarbonetos, xisto betuminoso e carvão. O enxofre é removido em um leito de óxido de zinco a uma temperatura reacional na faixa de 260°C a 454°C. Não ocorre, no entanto, menção à purificação de outros contaminantes, nem ao emprego para a produção de hidrogénio.  EP 0096970 discloses a process for removing organic sulfur compounds such as hydrogen sulfide, mercaptans, sulfides and disulfides present in ammonia streams generated in the processing of hydrocarbons, oil shale and coal. Sulfur is removed in a zinc oxide bed at a reaction temperature in the range of 260 ° C to 454 ° C. However, no mention is made of the purification of other contaminants or of their use for hydrogen production.
O documento US 7,258,848 apresenta um processo para o tratamento de gases contendo amónia e sulfeto de hidrogénio. A amónia é removida pela lavagem dos gases com um ácido forte, por exemplo, ácido sulfúrico concentrado, de forma a converter à amónia em um sal. A solução aquosa ou o sal cristalizado de amónia podem ser empregados como fertilizante.  US 7,258,848 discloses a process for treating gases containing ammonia and hydrogen sulfide. Ammonia is removed by washing the gases with a strong acid, for example concentrated sulfuric acid, to convert the ammonia to a salt. The aqueous solution or crystallized ammonia salt may be employed as fertilizer.
Assim, os processos de purificação de correntes amoniacais geradas em unidades de águas ácidas são específicos para a remoção de compostos de enxofre. O estado da técnica carece de um processo que remova outros contaminantes, tais como compostos de halogênios, metais e hidrocarbonetos, e resulte em uma corrente amoniacal, que, empregada em um processo de reforma catalítica para a produção de hidrogénio, conduza a uma reduzida taxa de desativação dos catalisadores.  Thus, the purification processes of ammonia currents generated in acid water units are specific for the removal of sulfur compounds. The prior art lacks a process that removes other contaminants, such as halogen compounds, metals and hydrocarbons, and results in an ammoniacal current which, employed in a catalytic reforming process for hydrogen production, leads to a reduced rate. of catalyst deactivation.
SUMÁRIO DA INVENÇÃO SUMMARY OF THE INVENTION
É objeto da presente invenção um processo para a produção de hidrogénio por decomposição catalítica de soluções amoniacais proveniente de unidades de água ácida. Tal processo envolve a purificação de uma corrente amoniacal e o emprego desta corrente purificada como carga em um processo de reforma a vapor. A etapa de purificação remove impurezas tais como enxofre, halogênios, metais e hidrocarbonetos olefínicos. A corrente purificada é conduzida para um forno reformador, que faz parte do processo de reforma a vapor, para a conversão da amónia em hidrogénio. The object of the present invention is a process for the production of hydrogen by catalytic decomposition of ammonia solutions. from acid water units. Such a process involves the purification of an ammonia stream and the use of this purified stream as a charge in a steam reforming process. The purification step removes impurities such as sulfur, halogens, metals and olefin hydrocarbons. The purified stream is fed to a reforming furnace, which is part of the steam reforming process, for the conversion of ammonia to hydrogen.
Adicionalmente, é sintetizado um catalisador, cujas características possibilitam seu emprego para a purificação da corrente amoniacal com uma reduzida taxa de desativação.  Additionally, a catalyst is synthesized, whose characteristics make it possible to use it to purify the ammonia current with a low deactivation rate.
DESCRIÇÃO DETALHADA DA INVENÇÃO  DETAILED DESCRIPTION OF THE INVENTION
Refere-se a presente invenção a um processo para produção de hidrogénio por decomposição catalítica de soluções amoniacais provenientes de unidades de água ácida. O objetivo é alcançado por meio de um processo realizado em duas etapas principais, a saber: uma primeira etapa de purificação da corrente amoniacal, que compreende um pré-tratamento da corrente amoniacal em uma pluralidade de leitos de catalisadores, e, uma segunda etapa, que consiste na submissão da corrente tratada à reforma a vapor.  The present invention relates to a process for producing hydrogen by catalytic decomposition of ammonia solutions from acidic water units. The objective is achieved by a process carried out in two main steps, namely: a first ammonia current purification step comprising a pretreatment of the ammonia current in a plurality of catalyst beds, and a second step, which consists in the submission of the treated current to the steam reform.
Adicionalmente, para a realização do processo, é sintetizado um catalisador, cujas características possibilitam seu emprego na etapa de purificação da corrente amoniacal.  Additionally, to perform the process, a catalyst is synthesized, the characteristics of which enable its use in the purification step of the ammoniacal current.
Em linhas gerais a invenção trata de um processo contínuo para a produção de hidrogénio, realizado em duas etapas, sendo que:  Generally speaking, the invention is a continuous process for the production of hydrogen, carried out in two steps:
a primeira etapa compreende os seguintes passos: The first step comprises the following steps:
- remover metais e cloretos existentes na corrente amoniacal gasosa proveniente de unidades de água ácida, em um primeiro leito, composto por materiais escolhidos entre alumina, sílica-aluminas, sílica, titânio, magnésio, zircônio e misturas destes, mantido a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma primeira corrente de efluente; - remove metals and chlorides in the gaseous ammonia stream from acidic water units in a first bed consisting of materials chosen from alumina, silica-alumina, silica, titanium, magnesium, zirconium and mixtures thereof, maintained at a reaction temperature in 300 ° C range 650 ° C under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a first stream of effluent;
- transformar compostos orgânicos de cloretos e enxofre, contaminantes da primeira corrente de efluente, em ácido clorídrico e sulfeto de hidrogénio, e, adicionalmente, hidrogenar compostos olefínicos, em um segundo leito, composto por catalisadores de hidrotratamento escolhidos entre cobalto- molibdênio e níquel-molibdênio, suportados em alumina, e alternativamente, suportados em óxidos de zinco, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma segunda corrente de efluente; - transform organic chloride and sulfur compounds, contaminants of the first effluent stream, into hydrochloric acid and hydrogen sulfide, and additionally hydrogenate olefinic compounds into a second bed consisting of hydrotreating catalysts chosen from cobalt-molybdenum and nickel. supported on alumina and alternatively supported on zinc oxides at a reaction temperature in the range 300 ° C to 650 ° C under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a second effluent stream;
- remover sulfeto de hidrogénio e compostos inorgânicos de cloro, tais como ácido clorídrico, cloreto de amónia, e, adicionalmente, transformar parcialmente a amónia em hidrogénio e nitrogénio, em um terceiro leito, composto por catalisadores promovidos por materiais escolhidos entre os metais alcalinos e alcalinos terrosos, suportados em materiais escolhidos entre óxidos de zinco, alumina, sílicas-alumina e misturas destes, e tendo óxido de níquel como fase ativa, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma terceira corrente de efluente; removing hydrogen sulfide and inorganic chlorine compounds such as hydrochloric acid, ammonium chloride and additionally partially transforming ammonia into hydrogen and nitrogen into a third bed consisting of catalysts promoted by materials selected from alkali metals and alkaline earth based on materials chosen from zinc oxide, alumina, silica alumina and mixtures thereof and having nickel oxide as the active phase at a reaction temperature in the range 300 ° C to 650 ° C under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a third stream of effluent;
- remover compostos inorgânicos e orgânicos de enxofre e cloro existentes na terceira corrente de efluente, em um quarto leito, composto por catalisadores escolhidos entre aqueles contendo óxidos de zinco e cobre, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2 para obter uma corrente amoniacal purificada; - removing inorganic and organic sulfur and chlorine compounds from the third effluent stream in a fourth bed consisting of catalysts selected from those containing zinc and copper oxides at a reaction temperature in the range 300 ° C to 650 ° C, under pressure in the range of 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a purified ammonia current;
a segunda etapa compreende os seguintes passos: The second step comprises the following steps:
- alimentar a corrente amoniacal purificada em um reator, para a 4 - feed the purified ammonia current into a reactor for 4
10 produção de hidrogénio pelo processo de reforma a vapor, para obter uma corrente gasosa rica em hidrogénio;  Producing hydrogen by the steam reforming process to obtain a hydrogen rich gas stream;
- purificar a corrente gasosa rica em hidrogénio, para obter o produto final hidrogénio.  purifying the hydrogen rich gas stream to obtain the final hydrogen product.
A presente invenção pode ser aplicada a unidades existentes de produção de hidrogénio pelo processo de reforma a vapor, bastando adequar à seção de pré-tratamento da unidade existente à pluralidade de leitos.  The present invention can be applied to existing hydrogen production units by the steam reforming process by simply adapting the pretreatment section of the existing unit to the plurality of beds.
Além da corrente amoniacal, uma corrente de hidrocarbonetos também pode ser alimentada na primeira etapa do processo. A corrente de hidrocarbonetos corresponde à carga que é normalmente empregada em unidades industriais de produção de hidrogénio pelo processo de reforma a vapor. A corrente amoniacal corresponde a uma fração da carga de hidrocarbonetos, e encontra se na faixa entre 1 % a 10% em volume. Os hidrocarbonetos podem ser escolhidos entre gás natural, gás liquefeito de petróleo, nafta e uma mistura destes, em quaisquer proporções.  In addition to the ammonia stream, a hydrocarbon stream can also be fed in the first process step. The hydrocarbon stream corresponds to the charge that is normally employed in industrial hydrogen production units by the steam reforming process. The ammoniacal current corresponds to a fraction of the hydrocarbon charge and is in the range of 1% to 10% by volume. Hydrocarbons may be chosen from natural gas, liquefied petroleum gas, naphtha and a mixture thereof in any proportion.
No processo de purificação, ocorre preferencialmente a adição de hidrogénio à carga, com o objetivo de evitar a formação de coque no segundo leito catalítico.  In the purification process, hydrogen is preferably added to the filler to prevent coke formation in the second catalytic bed.
No terceiro leito, a inclusão de óxido de níquel na formulação do catalisador permite realizar a transformação parcial da amónia em hidrogénio e nitrogénio. O catalisador é sintetizado contendo óxido de níquel como fase ativa, suportado pelos materiais escolhidos entre óxido de zinco, alumina e uma mistura destes, e promovido por materiais escolhidos entre os metais alcalinos e alcalinos terrosos.  In the third bed, the inclusion of nickel oxide in the catalyst formulation enables the partial transformation of ammonia to hydrogen and nitrogen. The catalyst is synthesized containing nickel oxide as the active phase, supported by materials chosen from zinc oxide, alumina and a mixture thereof, and promoted by materials chosen from alkaline and alkaline earth metals.
O catalisador é obtido por meio de técnica de impregnação a seco, a partir da impregnação de um suporte, selecionado entre alumina e óxido de zinco, com uma solução de hidróxido do metal, para obter um material do tipo K/alumina ou K/ZnO. O material é seco e calcinado. A seguir, o material calcinado é impregnado com solução de nitrato de níquel, seco e novamente calcinado, dando origem ao catalisador cujas características possibilitam seu emprego para a purificação da corrente amoniacal com uma reduzida taxa de desativação. A síntese do catalisador será apresentada em detalhe mais adiante. The catalyst is obtained by dry impregnation technique from the impregnation of a support selected from alumina and zinc oxide with a metal hydroxide solution to obtain a material of type K / alumina or K / ZnO. . The material is dry and calcined. The calcined material is then impregnated with nickel nitrate solution, dried and calcined again, giving rise to the catalyst whose characteristics allow its use for the purification of the ammonia current with a low deactivation rate. Catalyst synthesis will be presented in detail below.
O quarto leito é composto por materiais que podem ser escolhidos entre óxidos de zinco e cobre em teores acima de 50% em massa. Podem ser usados, por exemplo, catalisadores comerciais de deslocamento a baixa temperatura (LTS), conhecidos na técnica pelo termo em inglês "low temperature shift", utilizados em processos de produção de hidrogénio pela reforma a vapor.  The fourth bed is composed of materials that can be chosen from zinc and copper oxides in contents above 50% by mass. For example, commercial low temperature shift (LTS) catalysts known in the art by the term "low temperature shift" used in steam reforming hydrogen production processes may be used.
Os leitos empregados na primeira etapa são montados dentro de reatores. Cada reator contém um único tipo de leito, somando quatro leitos e quatro reatores diferentes. Alternativamente, a pluralidade de leitos pode estar contida em um único reator. O arranjo dos leitos em um único reator, ou em vários, é determinado pela capacidade volumétrica da unidade e pelos custos relativos dos equipamentos. O volume de cada leito deve ser selecionado em função do teor de contaminantes presentes na corrente amoniacal, além do tempo de campanha projetado para uma unidade industrial.  The beds used in the first stage are mounted inside reactors. Each reactor contains a single bed type, totaling four beds and four different reactors. Alternatively, the plurality of beds may be contained in a single reactor. The arrangement of beds in a single or several reactors is determined by the volumetric capacity of the unit and the relative costs of the equipment. The volume of each bed should be selected according to the content of contaminants present in the ammonia stream, as well as the campaign time projected for an industrial unit.
O emprego do primeiro e do segundo leito, em uma configuração industrial da presente invenção, é determinado pelo tipo de contaminantes presentes. Assim, em uma carga livre de metais, o emprego do primeiro leito não é necessário. Em uma carga livre de enxofre orgânico, o emprego do segundo leito não é necessário. O emprego do quarto leito, para a remoção final de compostos inorgânicos e orgânicos contendo enxofre e cloretos, é determinado pelo teor de contaminantes permitido no produto, além do tempo objetivo de campanha do reformador de uma unidade industrial.  The use of the first and second beds in an industrial configuration of the present invention is determined by the type of contaminants present. Thus, in a metal free load, the use of the first bed is not necessary. In a load free of organic sulfur, the use of the second bed is not necessary. The use of the fourth bed for the final removal of inorganic and organic compounds containing sulfur and chlorides is determined by the contaminant content allowed in the product, as well as the objective campaign time of the reformer of an industrial unit.
Na segunda etapa do processo, a reforma a vapor, a corrente amoniacal purificada é encaminhada para um pré-reformador, e, alternativamente, a um reformador primário, comumente empregado no processo de reforma a vapor. Nestes equipamentos ocorre a conversão da amónia residual oriunda do terceiro leito em hidrogénio e nitrogénio. A corrente obtida após a reação de conversão deve ser tratada para a retirada de impurezas misturadas ao hidrogénio. In the second stage of the process, steam reforming, purified ammonia current is routed to a pre-reformer, and, alternatively, to a primary reformer, commonly employed in the steam reform process. In these devices, the residual ammonia from the third bed is converted into hydrogen and nitrogen. The stream obtained after the conversion reaction shall be treated to remove impurities mixed with hydrogen.
Os métodos de tratamento empregados são conhecidos do estado da técnica. A redução do teor de monóxido de carbono (CO) ocorre pela reação de deslocamento. A remoção de monóxido de carbono, dióxido de carbono, metano e nitrogénio, ocorre pelo emprego de um sistema de adsorção por variação de pressão (PSA).  The treatment methods employed are known from the state of the art. The reduction of carbon monoxide (CO) content occurs by the displacement reaction. The removal of carbon monoxide, carbon dioxide, methane and nitrogen occurs by the use of a pressure variation adsorption system (PSA).
O catalisador desenvolvido de acordo com a presente invenção é empregado no terceiro leito sendo capaz de decompor amónia e simultaneamente retirar cloreto (Cl) e enxofre (S) da corrente amoniacal. O catalisador pode ser escolhido entre um catalisador suportado em alumina, promovido por um metal alcalino ou alcalino terroso, preferencialmente o potássio, e com fase ativa de óxido de níquel (NiO/K/alumina) e um catalisador suportado em óxido de zinco, promovido por um metal alcalino ou alcalino terroso, preferencialmente o potássio, e com fase ativa de óxido de níquel (NiO/K/ZnO). Além da alumina e do óxido de zinco, pode-se utilizar como suporte a sílica-alumina, ou, ainda, misturas destes.  The catalyst developed according to the present invention is employed in the third bed being capable of decomposing ammonia and simultaneously removing chloride (Cl) and sulfur (S) from the ammonia stream. The catalyst can be chosen from an alumina supported catalyst, promoted by an alkaline or alkaline earth metal, preferably potassium, and with an active phase of nickel oxide (NiO / K / alumina) and a zinc oxide supported catalyst by an alkaline or alkaline earth metal, preferably potassium, and with an active nickel oxide phase (NiO / K / ZnO). In addition to alumina and zinc oxide, silica alumina or mixtures thereof may be used as a support.
O teor de metal alcalino empregado no catalisador está na faixa de 1% a 7% em massa, preferencialmente entre 2% a 4% em massa. O teor de óxido de níquel empregado no catalisador está na faixa de 5% e 40% em massa, preferencialmente entre 10% e 20% em massa. São obtidos catalisadores com área especifica na faixa de 15 m2/g a 30 m2/g. The alkali metal content employed in the catalyst is in the range 1% to 7% by weight, preferably 2% to 4% by weight. The nickel oxide content employed in the catalyst is in the range of 5% to 40% by weight, preferably between 10% to 20% by weight. Catalysts with specific area in the range of 15 m 2 / g to 30 m 2 / g are obtained.
Para síntese do catalisador são empregados procedimentos conhecidos da técnica e descritos detalhadamente nos exemplos que ilustram a presente invenção.  For catalyst synthesis procedures known in the art are employed and described in detail in the examples illustrating the present invention.
EXEMPLO 1 : Síntese do catalisador NiO/K/alumina. EXAMPLE 1: Synthesis of NiO / K / alumina catalyst.
Neste exemplo foi sintetizado o catalisador em suporte de alumina, promovido por potássio e fase ativa de óxido de níquel (NiO/K/alumina).In this example the alumina-supported catalyst was synthesized, promoted by potassium and active phase of nickel oxide (NiO / K / alumina).
O catalisador foi preparado com duzentos gramas de hidróxido de alumina Pural SB (Condea Chemie), impregnado com uma solução aquosa de 11 ,5 gramas de hidróxido de potássio (KOH) pela técnica da impregnação seca (técnica de volume de poros). O material assim obtido foi seco em temperaturas na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas e calcinado em temperatura em torno de 600°C por um período de tempo em torno de 4 horas. Após esse período de tempo, a temperatura de calcinação foi elevada para um valor em torno de 1.200°C por um período de tempo em torno de 1 hora para obter um material do tipo K/alumina. The catalyst was prepared with two hundred grams of Pural SB alumina hydroxide (Condea Chemie), impregnated with an aqueous solution of 11.5 grams of potassium hydroxide (KOH) by the dry impregnation technique (pore volume technique). The material thus obtained was dried at temperatures in the range of 100 ° C to 120 ° C for a period of time in the range of 8 hours to 12 hours and calcined at temperature around 600 ° C for a period of time around 4 ° C. hours After this time, the calcination temperature was raised to around 1,200 ° C for a time of about 1 hour to obtain a K / alumina type material.
Uma quantidade de cento e trinta e três gramas do material K/alumina foi impregnado com uma solução aquosa contendo 27,2 gramas de nitrato de níquel hexahidratado [Ni(N03)2.6H20] pela técnica da impregnação seca (técnica de volume de poros), seguido de secagem em temperatura na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas e calcinado em temperatura em torno de 450°C por um período de tempo em torno de 4 horas para obter um catalisador do tipo NiO/K/alumina. O catalisador assim obtido apresentou uma concentração de 3% em massa de potássio (K), 15% em massa de óxido de níquel (NiO) e área especifica de 27,7 m2/g, determinada pela técnica de adsorção de nitrogénio. One hundred and thirty-three grams of K / alumina material was impregnated with an aqueous solution containing 27.2 grams of nickel nitrate hexahydrate [Ni (N03) 2.6H20] by dry impregnation technique (pore volume technique). followed by drying at a temperature in the range of 100 ° C to 120 ° C for a period of time in the range of 8 hours to 12 hours and calcined at a temperature of around 450 ° C for a period of about 4 hours to obtain a NiO / K / alumina catalyst. The catalyst thus obtained had a concentration of 3% by weight of potassium (K), 15% by weight of nickel oxide (NiO) and a specific area of 27,7 m 2 / g determined by the nitrogen adsorption technique.
O catalisador é empregado para a conversão de amónia e remoção de cloreto e de enxofre.  The catalyst is employed for ammonia conversion and removal of chloride and sulfur.
EXEMPLO 2: Síntese do catalisador NiO/K/ZnO. EXAMPLE 2: Synthesis of NiO / K / ZnO Catalyst.
Neste exemplo foi sintetizado o catalisador em suporte de óxido de zinco, promovido por potássio e fase ativa de óxido de níquel (NiO/K/ZnO).  In this example the potassium-promoted zinc oxide support catalyst and nickel oxide active phase (NiO / K / ZnO) were synthesized.
O catalisador foi preparado com cento e cinquenta gramas de um óxido de zinco comercial, impregnado com uma solução aquosa de 3,01 gramas de hidróxido de potássio (KOH) pela técnica de volume de poros. O material assim obtido foi seco em temperatura em torno de 110°C e calcinado em temperatura em torno de 450°C por um período de tempo em torno de 4 horas para obter um material do tipo K/ZnO. The catalyst was prepared with one hundred and fifty grams of a commercial zinc oxide impregnated with an aqueous solution of 3.01 grams of potassium hydroxide (KOH) by pore volume technique. The material thus obtained was dried at a temperature of about 110 ° C and calcined at a temperature of about 450 ° C for a period of about 4 hours to obtain a K / ZnO type material.
Uma quantidade de noventa gramas do material K/ZnO foi impregnado com uma solução aquosa contendo 19,5 gramas de nitrato de níquel hexahidratado [Ni(N03)2.6H20] pela técnica de volume de poros, seguido de secagem em temperaturas na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas e calcinado em temperatura em torno de 450°C por um período de tempo em torno de 4 horas para obter um material do tipo NiO/K/ZnO. O catalisador assim obtido apresentou uma concentração de 2% em massa de potássio (K) e 15% em massa de óxido de níquel (NiO) e área especifica de 17,2 m2/g, determinada pela técnica de adsorção de nitrogénio. Ninety grams of the K / ZnO material was impregnated with an aqueous solution containing 19.5 grams of nickel nitrate hexahydrate [Ni (NO3) 2.6H20] by pore volume technique, followed by drying at temperatures in the range of 100 ° C. ° C to 120 ° C for a period of time in the range of 8 hours to 12 hours and calcined at a temperature of around 450 ° C for a period of about 4 hours to obtain a NiO / K / ZnO material . The catalyst thus obtained had a concentration of 2% by weight of potassium (K) and 15% by weight of nickel oxide (NiO) and a specific area of 17,2 m 2 / g determined by the nitrogen adsorption technique.
O catalisador é empregado para a conversão de amónia e remoção de cloreto e de enxofre.  The catalyst is employed for ammonia conversion and removal of chloride and sulfur.
EXEMPLO 3: Desempenho dos catalisadores - retenção de cloretos.  EXAMPLE 3: Catalyst Performance - Chloride Retention.
Neste exemplo foi comparada a capacidade de retenção de cloretos dos catalisadores da invenção, preparados de acordo com os Exemplos 1 e 2, em relação a catalisadores comerciais usados em processos do estado da técnica. Um primeiro catalisador selecionado trata-se de um catalisador comercial à base de níquel. Um segundo catalisador selecionado para a etapa de deslocamento a baixa temperatura ("low temperature shift" ou LTS) no processo de produção de hidrogénio pela reforma a vapor, é um catalisador comercial do tipo CuO/ZnO/AI20. In this example the chloride retention capacity of the catalysts of the invention prepared according to Examples 1 and 2 was compared to commercial catalysts used in prior art processes. A first selected catalyst is a commercial nickel-based catalyst. A second catalyst selected for the low temperature shift (LTS) step in the steam reforming hydrogen production process is a commercial CuO / ZnO / AI 20 type catalyst.
Os experimentos foram realizados em uma unidade de processo em escala de laboratório, contendo um reator de leito fixo de catalisador e empregando as seguintes condições experimentais:  The experiments were performed in a laboratory scale process unit, containing a catalyst fixed bed reactor and employing the following experimental conditions:
- pressão atmosférica;  - atmospheric pressure;
- temperatura de 350°C;  - temperature of 350 ° C;
- Massa de catalisador igual a 2,0 g; granulometria menor que 0,105 mm ou mesh 150. - Catalyst mass equal to 2,0 g; particle size less than 0.105 mm or 150 mesh.
Os catalisadores foram inicialmente pré-tratados em fluxo de hidrogénio em temperatura de 400°C pelo período de tempo de 60 minutos e a seguir resfriados para a temperatura de 350°C.  The catalysts were initially pretreated under hydrogen flow at a temperature of 400 ° C for a period of 60 minutes and then cooled to a temperature of 350 ° C.
O experimento consiste em fazer passar um fluxo de 40 mL/min. de hidrogénio em um saturador contendo ácido clorídrico concentrado PA mantido a temperatura de 10°C e alimentá-lo ao reator.  The experiment consists of passing a flow of 40 mL / min. of hydrogen in a saturator containing concentrated hydrochloric acid PA kept at a temperature of 10 ° C and feed it to the reactor.
Os catalisadores são comparados em relação ao tempo para se observar o aparecimento de cloreto no efluente do reator. Assumiu-se uma concentração média da solução de cloreto de hidrogénio de 34% (correspondendo a uma pressão de vapor do cloreto de hidrogénio sobre a solução de 26,4 mmHg conforme valores tabelados na literatura). O tempo para a ocorrência da "fuga" de cloreto foi utilizado para a estimativa da capacidade de retenção de cloreto (kg Cl/kg material).  The catalysts are compared over time to observe the appearance of chloride in the reactor effluent. An average hydrogen chloride solution concentration of 34% was assumed (corresponding to a vapor pressure of hydrogen chloride on the solution of 26.4 mmHg according to the tabulated values in the literature). The time for chloride "leakage" to occur was used to estimate chloride retention capacity (kg Cl / kg material).
O efluente do reator foi acompanhado por espectrometria de massas, monitorando-se o fragmento com a relação massa/carga igual a 36.  The reactor effluent was followed by mass spectrometry, monitoring the fragment with a mass / charge ratio of 36.
Os resultados são apresentados na Tabela 1 abaixo.  Results are presented in Table 1 below.
Figure imgf000016_0001
Figure imgf000016_0001
De acordo com a Tabela 1 , o material sintetizado no Exemplo 1 possui capacidade de retenção de cloreto superior em 75% em relação ao catalisador de metanação comercial (caso base). O catalisador sintetizado no Exemplo 2 possui capacidade de retenção de cloreto superior em 875% em relação ao catalisador de metanação comercial. According to Table 1, the material synthesized in Example 1 has a 75% higher chloride retention capacity than the commercial methanation catalyst (base case). The catalyst synthesized in Example 2 has an 875% higher chloride retention capacity relative to the commercial methanation catalyst.
EXEMPLO 4: Desempenho dos catalisadores - retenção de enxofre.  EXAMPLE 4: Catalyst Performance - Sulfur Retention.
Neste exemplo foi comparada a capacidade de retenção de enxofre dos catalisadores da invenção, preparados de acordo com os Exemplos 1 e 2, em relação a catalisadores do estado da técnica. Os catalisadores comerciais selecionados foram os mesmos empregados no Exemplo 3.  In this example the sulfur holding capacity of the catalysts of the invention prepared according to Examples 1 and 2 was compared to prior art catalysts. The selected commercial catalysts were the same as those employed in Example 3.
Os experimentos foram realizados em uma unidade de processo em escala de laboratório, empregando as seguintes condições experimentais:  The experiments were performed in a laboratory scale process unit, employing the following experimental conditions:
- pressão atmosférica;  - atmospheric pressure;
- temperatura de 350°C;  - temperature of 350 ° C;
- massa de catalisador igual a 3,0 g; granulometria menor que 0,105 mm.  - catalyst mass of 3,0 g; particle size less than 0.105 mm.
Os catalisadores foram inicialmente pré-tratados em fluxo de hidrogénio em temperatura de 400°C pelo período de tempo de 60 minutos e a seguir resfriados para a temperatura de 350°C.  The catalysts were initially pretreated under hydrogen flow at a temperature of 400 ° C for a period of 60 minutes and then cooled to a temperature of 350 ° C.
O enxofre foi alimentado ao reator através da passagem de um fluxo de 8 ml por minuto de uma mistura gasosa contendo 15% de sulfeto de hidrogénio em hidrogénio. A presença de sulfeto de hidrogénio foi detectada no efluente do reator pelo uso de ampolas para a detecção de sulfeto de hidrogénio, conhecido como ampola Drager. Os catalisadores são comparados em relação ao tempo para se observar o aparecimento de enxofre no efluente do reator e este valor utilizado para estimar a capacidade de retenção de enxofre (kg S / kg material). Os resultados são apresentados na Tabela 2 abaixo.  Sulfur was fed to the reactor by passing an 8 ml flow per minute of a gas mixture containing 15% hydrogen sulfide in hydrogen. The presence of hydrogen sulfide was detected in the reactor effluent by the use of ampoules for the detection of hydrogen sulfide, known as the Drager ampoule. The catalysts are compared over time to observe the appearance of sulfur in the reactor effluent and this value used to estimate sulfur retention capacity (kg S / kg material). Results are presented in Table 2 below.
TABELA 2 TABLE 2
Exemplo 1 Exemplo 2 Catalisador Catalisador Example 1 Example 2 Catalyst Catalyst
CATALISADOR CATALYST
NiO/K/alumina NiO/K/ZnO Metanação LTS  NiO / K / alumina NiO / K / ZnO LTS methanation
Tempo de Fuga do  Escape Time
25 149 54 164 Enxofre (minutos)  25 149 54 164 Sulfur (minutes)
Capacidade de  Capacity of
Retenção (kg S/kg 0,037 0,219 0,079 0,241 material)
Figure imgf000018_0001
Retention (kg S / kg 0.037 0.219 0.079 0.241 material)
Figure imgf000018_0001
De acordo com a Tabela 2, o material sintetizado no Exemplo 2 possui capacidade de retenção de enxofre superior em 177% em relação ao catalisador de metanação comercial.  According to Table 2, the material synthesized in Example 2 has 177% higher sulfur retention capacity than the commercial methanation catalyst.
O catalisador comercial LTS, de acordo com o processo da presente invenção, pode ser utilizado para compor a pluralidade de leitos de purificação da corrente de água ácida, visto que possui capacidade de retenção de cloreto superior em 200% e capacidade de retenção de enxofre superior em 205% em relação ao catalisador de metanação.  The commercial catalyst LTS according to the process of the present invention can be used to make up the plurality of acid water stream purification beds as it has 200% superior chloride retention capacity and superior sulfur retention capacity. 205% over the methanation catalyst.
Estes exemplos ilustram a maior capacidade de retenção de cloretos e enxofre pelos catalisadores preparados de acordo com a presente invenção quando comparados aos catalisadores do estado da técnica. EXEMPLO 5: Desempenho dos catalisadores - decomposição de amónia.  These examples illustrate the increased chloride and sulfur retention capacity of the catalysts prepared according to the present invention as compared to prior art catalysts. EXAMPLE 5: Catalyst Performance - Ammonia Decomposition.
Neste exemplo foi comparada a atividade de decomposição da amónia por catalisadores da invenção, preparados de acordo com os Exemplos 1 e 2, em relação a catalisadores do estado da técnica. Os catalisadores comerciais selecionados foram os mesmos empregados nos exemplos anteriores.  In this example the ammonia decomposition activity of catalysts of the invention prepared according to Examples 1 and 2 was compared to prior art catalysts. The selected commercial catalysts were the same as those employed in the previous examples.
Os experimentos foram realizados em uma unidade de processo em escala de laboratório, empregando as seguintes condições experimentais:  The experiments were performed in a laboratory scale process unit, employing the following experimental conditions:
- pressão atmosférica;  - atmospheric pressure;
- temperatura na faixa de 450°C a 550°C;  - temperature in the range from 450 ° C to 550 ° C;
- massa de catalisador igual a 0,5 g; granulometria menor que 0,105 mm.  - catalyst mass equal to 0,5 g; particle size less than 0.105 mm.
Os catalisadores foram inicialmente pré-tratados em fluxo de hidrogénio em temperatura de 450°C pelo período de tempo de 60 minutos. A amónia foi alimentada ao reator através da passagem de vazões situadas na faixa de 10 mL/min. a 40 mL/min. de hidrogénio em um saturador contendo hidróxido de amónio concentrado PA, na concentração situada na faixa de 28% a 30% de amónia, mantido a temperatura de 10°C. O efluente do reator foi acompanhado por espectrometria de massas, monitorando-se os fragmentos com a relação massa/carga de 17 e 28 para amónia e nitrogénio, respectivamente. The catalysts were initially pretreated under hydrogen flow at 450 ° C for a time period of 60 minutes. Ammonia was fed to the reactor by passing flow rates in the range of 10 mL / min. at 40 mL / min. of hydrogen in a saturator containing concentrated ammonium hydroxide PA at a concentration in the range of 28 to 30% ammonia maintained at a temperature of 10 ° C. The reactor effluent was monitored by mass spectrometry, monitoring the fragments with the mass / charge ratio of 17 and 28 for ammonia and nitrogen, respectively.
Os catalisadores são comparados em relação à atividade de conversão da amónia (%), variando se o parâmetro velocidade espacial horária do gás (GHSV) e a temperatura de reação, conforme resultados apresentados na Tabela 3 adiante.  The catalysts are compared for ammonia conversion activity (%) by varying the hourly space gas velocity (GHSV) parameter and the reaction temperature, as shown in Table 3 below.
Os resultados da Tabela 3 mostram que o catalisador sintetizado no The results from Table 3 show that the catalyst synthesized in the
Exemplo 1 apresenta atividade para a decomposição da amónia em hidrogénio e nitrogénio superior ao observado no catalisador de metanação. Ambos os catalisadores apresentam uma atividade significativa de decomposição da amónia somente em valores de temperatura acima de 450°C. Example 1 shows greater decomposition activity of ammonia in hydrogen and nitrogen than observed in the methanation catalyst. Both catalysts exhibit significant ammonia decomposition activity only at temperatures above 450 ° C.
Figure imgf000019_0001
Figure imgf000019_0001
De acordo com a presente invenção, não é necessário que ocorra a reação de decomposição de amónia simultaneamente com o tratamento da corrente para remoção de contaminantes, tais como enxofre e cloreto, uma vez que tal reação irá ocorrer à jusante da etapa de purificação, na etapa de reforma primária do processo de produção de hidrogénio pela reforma a vapor. Em certas situações, no entanto, tais como a de limitado volume do catalisador de reforma primária ou elevada vazão de amónia em mistura com a corrente de hidrocarbonetos, é desejável que ocorra parte da transformação da amónia em hidrogénio simultaneamente à remoção de contaminantes, tais como cloretos e enxofre. Portanto, é possível conciliar uma elevada capacidade de retenção de contaminantes com uma alta conversão parcial da amónia empregando-se mistura de leitos dos materiais sintetizados de acordo com os Exemplos 1 e 2 e catalisador de LTS. According to the present invention, it is not necessary for the decomposition reaction of ammonia to occur simultaneously with the treatment of the stream to remove contaminants such as sulfur and chloride, as such reaction will occur downstream of the purification step in primary reform stage of the hydrogen production process by steam reforming. In certain situations, however, such as limited volume of the primary reforming catalyst or high flow rate of ammonia in admixture with the hydrocarbon stream, it is desirable that part of the transformation of ammonia to hydrogen occurs simultaneously with the removal of contaminants such as chlorides and sulfur. Therefore, it is possible to reconcile a high contaminant holding capacity with a high partial conversion of ammonia by employing bed mixtures of materials synthesized according to Examples 1 and 2 and LTS catalyst.
Os resultados confirmam o grande potencial da aplicação do processo para a produção de hidrogénio por decomposição catalítica de soluções amoniacais, bem como o potencial para a purificação da corrente amoniacal pelo catalisador sintetizado.  The results confirm the great potential of the application of the process for hydrogen production by catalytic decomposition of ammonia solutions, as well as the potential for ammonia current purification by the synthesized catalyst.
Os exemplos demonstram que é possível aumentar a retenção de cloreto em até 875% e aumentar a retenção de enxofre em até 177%, com o emprego dos catalisadores sintetizados na presente invenção, em relação a catalisadores de metanação comerciais. O catalisador comercial LTS que de acordo com a presente invenção, pode ser utilizado para compor a pluralidade de leitos de purificação da corrente de água ácida, possui capacidade de retenção de cloreto superior em 200% e capacidade de retenção de enxofre superior em 205% em relação aos catalisadores de metanação comerciais.  The examples demonstrate that chloride retention can be increased by up to 875% and sulfur retention by up to 177% by using the catalysts synthesized in the present invention over commercial methanation catalysts. The commercial catalyst LTS which according to the present invention can be used to make up the plurality of acid water stream purification beds has 200% higher chloride holding capacity and 205% higher sulfur holding capacity. regarding commercial methanation catalysts.
Tornam-se evidentes, portanto, as vantagens da presente invenção em relação ao estado da técnica, a saber:  Therefore, the advantages of the present invention in relation to the state of the art, as follows:
- provê um método relativamente de baixo custo para a purificação de correntes amoniacais proveniente de unidades de água acida; - provides a relatively low cost method for the purification of ammonia currents from acidic water units;
- propicia a purificação de correntes amoniacais com alta concentração de contaminantes; - provides the purification of ammonia currents with high concentration of contaminants;
- permite produzir hidrogénio a partir de correntes com alta concentração de amónia e outros contaminantes, empregando processo de reforma catalítica a vapor; e - pode ser aplicado em unidades já instaladas de produção de hidrogénio em larga escala pelo processo de reforma a vapor, sem necessidade de custos adicionais de capital. - makes it possible to produce hydrogen from streams with a high concentration of ammonia and other contaminants using a catalytic steam reforming process; and - can be applied to already installed large-scale hydrogen production units by the steam reforming process without the need for additional capital costs.
Embora a presente invenção tenha sido descrita em sua forma de realização preferida, o conceito principal que norteia a invenção, se mantém preservado quanto ao caráter inovador, onde aqueles usualmente versados na técnica poderão vislumbrar e praticar variações, modificações, alterações, adaptações e equivalentes cabíveis e compatíveis ao meio de trabalho em questão, sem, contudo se afastar da abrangência do espírito e escopo da presente invenção, que estão representados pelas reivindicações que se seguem.  Although the present invention has been described in its preferred embodiment, the main concept underlying the invention remains preserved as to its innovative character, where those of ordinary skill in the art may envision and practice appropriate variations, modifications, alterations, adaptations and equivalents. and compatible with the working environment in question, without, however, departing from the scope of the spirit and scope of the present invention, which are represented by the following claims.

Claims

REIVINDICAÇÕES
1- PROCESSO PARA PRODUÇÃO DE HIDROGÉNIO, caracterizado por compreender a decomposição catalítica de soluções amoniacais provenientes de unidades de águas ácidas, realizada em duas etapas, sendo uma primeira etapa de purificação da corrente amoniacal promovida em uma pluralidade de leitos catalíticos, e uma segunda etapa de reforma a vapor da corrente amoniacal purificada, segundo o qual: 1. Hydrogen production process, characterized by comprising the catalytic decomposition of ammonia solutions from acidic water units, carried out in two stages, being a first stage of purification of the ammonia stream promoted in a plurality of catalytic beds, and a second stage. steam reforming of the purified ammonia stream, according to which:
a primeira etapa de purificação da corrente amoniacal compreende os seguintes passos:  The first step of purifying the ammoniacal current comprises the following steps:
- remover metais e cloretos existentes na corrente amoniacal em um primeiro leito, composto por materiais escolhidos entre alumina, sílica-aluminas, sílica, titânio, magnésio, zircônio e misturas destes, mantido a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma primeira corrente de efluente; - remove metals and chlorides from the ammonia stream in a first bed, consisting of materials chosen from alumina, silica alumina, silica, titanium, magnesium, zirconium and mixtures thereof, maintained at a reaction temperature in the range 300 ° C to 650 ° C, under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 , to obtain a first stream of effluent;
- transformar compostos orgânicos de cloretos e enxofre, contaminantes da primeira corrente de efluente, em ácido clorídrico e sulfeto de hidrogénio, e, adicionalmente, hidrogenar compostos olefínicos, em um segundo leito, composto por catalisadores de hidrotratamento escolhidos entre cobalto- molibdênio e níquel-molibdênio, suportados em alumina, e alternativamente, suportados em óxidos de zinco, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma segunda corrente de efluente; - transform organic chloride and sulfur compounds, contaminants of the first effluent stream, into hydrochloric acid and hydrogen sulfide, and additionally hydrogenate olefinic compounds into a second bed consisting of hydrotreating catalysts chosen from cobalt-molybdenum and nickel. supported on alumina and alternatively supported on zinc oxides at a reaction temperature in the range 300 ° C to 650 ° C under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a second effluent stream;
- remover sulfeto de hidrogénio e compostos inorgânicos de cloro, tais como ácido clorídrico, cloreto de amónia, contaminantes da segunda corrente de efluente e, adicionalmente, transformar parcialmente a amónia em hidrogénio e nitrogénio, em um terceiro leito, composto por catalisadores promovidos por materiais escolhidos entre os metais alcalinos e alcalinos terrosos, suportados em materiais escolhidos entre óxidos de zinco, alumina, sílicas-alumina e misturas destes, e tendo óxido de níquel como fase ativa, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2, para obter uma terceira corrente de efluente; - remove hydrogen sulfide and inorganic chlorine compounds such as hydrochloric acid, ammonium chloride, contaminants from the second effluent stream and additionally partially transform the ammonia into hydrogen and nitrogen into a third bed, consisting of catalysts promoted by materials selected from alkaline and alkaline earth metals, supported on materials chosen from zinc oxides, alumina, silica-alumina and mixtures thereof, and having nickel oxide as the active phase at a reaction temperature in the range from 300 ° C to 650 ° C under pressure in the range 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a third stream of effluent;
- remover compostos inorgânicos e orgânicos de enxofre e cloro existentes na terceira corrente de efluente, em um quarto leito, composto por catalisadores escolhidos entre aqueles contendo óxidos de zinco e cobre, a uma temperatura reacional na faixa de 300°C a 650°C, sob pressão na faixa de 1 kgf/cm2 a 40 kgf/cm2 para obter uma corrente amoniacal purificada; - removing inorganic and organic sulfur and chlorine compounds from the third effluent stream in a fourth bed consisting of catalysts selected from those containing zinc and copper oxides at a reaction temperature in the range 300 ° C to 650 ° C, under pressure in the range of 1 kgf / cm 2 to 40 kgf / cm 2 to obtain a purified ammonia current;
a segunda etapa compreende os seguintes passos:  The second step comprises the following steps:
- alimentar a corrente amoniacal purificada em um reator, para a produção de hidrogénio pelo processo de reforma a vapor, para obter uma corrente gasosa rica em hidrogénio;  feeding the purified ammonia stream into a reactor for the production of hydrogen by the steam reforming process to obtain a hydrogen rich gas stream;
- purificar a corrente gasosa rica em hidrogénio, para obter o produto final hidrogénio.  purifying the hydrogen rich gas stream to obtain the final hydrogen product.
2- PROCESSO PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 1 , caracterizado por a corrente de solução amoniacal corresponder entre 1 % a 10% em volume da carga de hidrocarbonetos alimentada ao processo.  Hydrogen production process according to claim 1, characterized in that the ammonia solution stream corresponds to between 1% and 10% by volume of the hydrocarbon feedstock fed to the process.
3- PROCESSO PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 1 , caracterizado por o arranjo dos leitos ser determinado pela capacidade volumétrica da unidade e o volume de cada leito ser selecionado em função do teor de contaminantes presentes na corrente amoniacal.  Hydrogen production process according to claim 1, characterized in that the arrangement of the beds is determined by the volumetric capacity of the unit and the volume of each bed is selected as a function of the contaminant content present in the ammonia stream.
4- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, por decomposição catalítica de soluções amoniacais provenientes de unidades de águas ácidas caracterizado por ser composto por catalisadores promovidos por materiais escolhidos entre os metais alcalinos e alcalinos terrosos, suportados em materiais escolhidos entre óxidos de zinco, alumina, sílicas-alumina e misturas destes, e tendo óxido de níquel como fase ativa, sendo tal catalisador empregado em pelo menos um leito catalítico de um processo para a produção de hidrogénio de acordo com a reivindicação 1. 4- CATALYST FOR HYDROGEN PRODUCTION by catalytic decomposition of ammonia solutions from acid waters characterized by catalysts promoted by materials chosen from alkaline and alkaline earth metals, supported on materials chosen from zinc oxides, alumina, silica-alumina and mixtures thereof, and having nickel oxide as the active phase, such catalyst being employed in at least one catalytic bed of a hydrogen production process according to claim 1.
5- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 4, caracterizado por ser sintetizado por meio da impregnação a seco de um suporte selecionado entre alumina, óxido de zinco, ou ainda, misturas destes, com uma solução de pelo menos um hidróxido de metal alcalino, ou alcalinos terrosos, tendo incorporado óxido de níquel como fase ativa.  Hydrogen production catalyst according to Claim 4, characterized in that it is synthesized by dry impregnation of a support selected from alumina, zinc oxide or mixtures thereof with a solution of at least one hydroxide. alkali metal or earth alkaline, having incorporated nickel oxide as the active phase.
6- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com as reivindicações 4 e 5, caracterizado por as partículas de catalisadores obtidas possuírem área especifica na faixa de 15jn2/g a 30 m2/g. Hydrogen production catalyst according to claims 4 and 5, characterized in that the catalyst particles obtained have a specific area in the range 15jn 2 / g and 30 m 2 / g.
7- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com as reivindicações 4 e 5, caracterizado por o teor de metal alcalino empregado no catalisador estar na faixa de 1 % a 7% em massa e o teor de óxido de níquel empregado no catalisador está na faixa de 5% e 40% em massa,.  Hydrogen production catalyst according to claims 4 and 5, characterized in that the alkali metal content employed in the catalyst is in the range of 1% to 7% by weight and the nickel oxide content employed in the catalyst is in the range. 5% and 40% by mass.
8- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 6, caracterizado por o teor de metal alcalino estar entre 2% a 4% em massa.  8. Hydrogen production catalyst according to claim 6, characterized in that the alkali metal content is between 2% and 4% by mass.
9- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 6, caracterizado por o teor de óxido de níquel estar entre 10% e 20% em massa. Hydrogen production catalyst according to claim 6, characterized in that the nickel oxide content is between 10% and 20% by mass.
10- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 4, caracterizado por ser sintetizado por meio da impregnação a seco de um suporte selecionado entre alumina, óxido de zinco, ou ainda, misturas destes, com uma solução de pelo menos um hidróxido de metal alcalino, ou alcalinos terrosos, tendo incorporado óxido de níquel como fase ativa. Hydrogen production catalyst according to claim 4, characterized in that it is synthesized by dry impregnation of a support selected from alumina, oxide of zinc, or mixtures thereof, with a solution of at least one alkali metal hydroxide or earth alkali having nickel oxide as the active phase.
11- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 4, caracterizado por a síntese do catalisador compreender as seguintes etapas:  Catalyst for the production of hydrogen according to claim 4, characterized in that the catalyst synthesis comprises the following steps:
- impregnar o hidróxido de alumina com uma solução aquosa de hidróxido de potássio, e secar o material em temperaturas na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas;  - impregnating alumina hydroxide with an aqueous potassium hydroxide solution, and drying the material at temperatures ranging from 100 ° C to 120 ° C for a period of time ranging from 8 hours to 12 hours;
- calcinar o material em temperatura em torno de 600°C por um período de tempo em torno de 4 horas;  - calcining the material at a temperature of around 600 ° C for a period of time of about 4 hours;
- elevar a temperatura de calcinação para um valor em torno de 1.200°C pelo período de tempo em torno de 1 hora para obter um material K/alumina;  - raise the calcination temperature to around 1,200 ° C for a period of time around 1 hour to obtain a K / alumina material;
- impregnar o material K/alumina com uma solução aquosa de nitrato de níquel hexahidratado, e secar o material em temperaturas na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas;  - impregnating the K / alumina material with an aqueous solution of nickel nitrate hexahydrate, and drying the material at temperatures in the range 100 ° C to 120 ° C for a period of time ranging from 8 hours to 12 hours;
- calcinar o material impregnado em temperatura em torno de 450°C por um período de tempo em torno de 4 horas; e  - calcining the impregnated material at a temperature of around 450 ° C for a period of time of about 4 hours; and
- elevar a temperatura de calcinação para um valor em torno de 1.200°C pelo período de tempo em torno de 1 hora para obter um catalisador do tipo NiO/K/alumina.  - raise the calcination temperature to around 1,200 ° C for a period of time around 1 hour to obtain a NiO / K / alumina catalyst.
12- CATALISADOR PARA PRODUÇÃO DE HIDROGÉNIO, de acordo com a reivindicação 4, caracterizado por a síntese do catalisador compreender as seguintes etapas:  Catalyst for the production of hydrogen according to claim 4, characterized in that the catalyst synthesis comprises the following steps:
- impregnar o óxido de zinco com uma solução aquosa de hidróxido de potássio, e secar o material em temperatura no entorno de 110°C; - calcinar o material em temperatura em torno de 450°C por um período de tempo em torno de 4 horas, para obter um material K/ZnO; - impregnate the zinc oxide with an aqueous potassium hydroxide solution, and dry the material at a temperature around 110 ° C; calcining the material at a temperature of about 450 ° C for a period of time of about 4 hours to obtain a K / ZnO material;
- impregnar o material K/ZnO com uma solução aquosa de nitrato de níquel hexahidratado, e secar o material em temperaturas na faixa de 100°C a 120°C por um período de tempo na faixa de 8 horas a 12 horas;  - impregnating the K / ZnO material with an aqueous nickel nitrate hexahydrate solution, and drying the material at temperatures in the range 100 ° C to 120 ° C for a period of time ranging from 8 hours to 12 hours;
- calcinar o material impregnado em temperatura em torno de 450°C por um período de tempo em torno de 4 horas para obter um catalisador do tipo NiO/K/ZnO.  calcining the impregnated material at a temperature of about 450 ° C for a period of about 4 hours to obtain a NiO / K / ZnO catalyst.
PCT/BR2013/000504 2013-11-22 2013-11-22 Hydrogen production method and catalyst WO2015074127A1 (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106492868A (en) * 2016-09-28 2017-03-15 电子科技大学 Catalyst and preparation method thereof and the method for photocatalytic hydrogen production by water decomposition
US11539063B1 (en) 2021-08-17 2022-12-27 Amogy Inc. Systems and methods for processing hydrogen
US11697108B2 (en) 2021-06-11 2023-07-11 Amogy Inc. Systems and methods for processing ammonia
US11724245B2 (en) 2021-08-13 2023-08-15 Amogy Inc. Integrated heat exchanger reactors for renewable fuel delivery systems
US11795055B1 (en) 2022-10-21 2023-10-24 Amogy Inc. Systems and methods for processing ammonia
US11834334B1 (en) 2022-10-06 2023-12-05 Amogy Inc. Systems and methods of processing ammonia
US11834985B2 (en) 2021-05-14 2023-12-05 Amogy Inc. Systems and methods for processing ammonia
US11866328B1 (en) 2022-10-21 2024-01-09 Amogy Inc. Systems and methods for processing ammonia

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB966883A (en) *
US20070178034A1 (en) * 2006-01-31 2007-08-02 Hojlund Nielsen Poul E Process for the production of hydrogen
US20120015802A1 (en) * 2009-03-17 2012-01-19 Junji Okamura Catalyst for production of hydrogen and process for producing hydrogen using the catalyst, and catalyst for combustion of ammonia, process for producing the catalyst and process for combusting ammonia using the catalyst
US20130156687A1 (en) * 2010-08-31 2013-06-20 Hitachi Zosen Corporation Ammonia oxidation/decomposition catalyst

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB966883A (en) *
US20070178034A1 (en) * 2006-01-31 2007-08-02 Hojlund Nielsen Poul E Process for the production of hydrogen
US20120015802A1 (en) * 2009-03-17 2012-01-19 Junji Okamura Catalyst for production of hydrogen and process for producing hydrogen using the catalyst, and catalyst for combustion of ammonia, process for producing the catalyst and process for combusting ammonia using the catalyst
US20130156687A1 (en) * 2010-08-31 2013-06-20 Hitachi Zosen Corporation Ammonia oxidation/decomposition catalyst

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106492868A (en) * 2016-09-28 2017-03-15 电子科技大学 Catalyst and preparation method thereof and the method for photocatalytic hydrogen production by water decomposition
CN106492868B (en) * 2016-09-28 2019-02-26 电子科技大学 The method of catalyst and preparation method thereof and photocatalytic hydrogen production by water decomposition
US11994061B2 (en) 2021-05-14 2024-05-28 Amogy Inc. Methods for reforming ammonia
US11994062B2 (en) 2021-05-14 2024-05-28 AMOGY, Inc. Systems and methods for processing ammonia
US12000333B2 (en) 2021-05-14 2024-06-04 AMOGY, Inc. Systems and methods for processing ammonia
US11834985B2 (en) 2021-05-14 2023-12-05 Amogy Inc. Systems and methods for processing ammonia
US11697108B2 (en) 2021-06-11 2023-07-11 Amogy Inc. Systems and methods for processing ammonia
US12097482B2 (en) 2021-06-11 2024-09-24 AMOGY, Inc. Systems and methods for processing ammonia
US11724245B2 (en) 2021-08-13 2023-08-15 Amogy Inc. Integrated heat exchanger reactors for renewable fuel delivery systems
US11769893B2 (en) 2021-08-17 2023-09-26 Amogy Inc. Systems and methods for processing hydrogen
US11764381B2 (en) 2021-08-17 2023-09-19 Amogy Inc. Systems and methods for processing hydrogen
US11843149B2 (en) 2021-08-17 2023-12-12 Amogy Inc. Systems and methods for processing hydrogen
US11539063B1 (en) 2021-08-17 2022-12-27 Amogy Inc. Systems and methods for processing hydrogen
US11834334B1 (en) 2022-10-06 2023-12-05 Amogy Inc. Systems and methods of processing ammonia
US11975968B2 (en) 2022-10-06 2024-05-07 AMOGY, Inc. Systems and methods of processing ammonia
US11912574B1 (en) 2022-10-06 2024-02-27 Amogy Inc. Methods for reforming ammonia
US11840447B1 (en) 2022-10-06 2023-12-12 Amogy Inc. Systems and methods of processing ammonia
US11866328B1 (en) 2022-10-21 2024-01-09 Amogy Inc. Systems and methods for processing ammonia
US11795055B1 (en) 2022-10-21 2023-10-24 Amogy Inc. Systems and methods for processing ammonia

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