CN117004438A - Paraffin hydrofining method - Google Patents

Paraffin hydrofining method Download PDF

Info

Publication number
CN117004438A
CN117004438A CN202210456905.4A CN202210456905A CN117004438A CN 117004438 A CN117004438 A CN 117004438A CN 202210456905 A CN202210456905 A CN 202210456905A CN 117004438 A CN117004438 A CN 117004438A
Authority
CN
China
Prior art keywords
paraffin
catalyst
hydrofining
type
pore volume
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202210456905.4A
Other languages
Chinese (zh)
Inventor
刘文洁
袁胜华
耿新国
穆福军
段日
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sinopec Dalian Petrochemical Research Institute Co ltd
China Petroleum and Chemical Corp
Original Assignee
Sinopec Dalian Petrochemical Research Institute Co ltd
China Petroleum and Chemical Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sinopec Dalian Petrochemical Research Institute Co ltd, China Petroleum and Chemical Corp filed Critical Sinopec Dalian Petrochemical Research Institute Co ltd
Priority to CN202210456905.4A priority Critical patent/CN117004438A/en
Publication of CN117004438A publication Critical patent/CN117004438A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10G—CRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G73/00—Recovery or refining of mineral waxes, e.g. montan wax
    • C10G73/42—Refining of petroleum waxes
    • C10G73/44—Refining of petroleum waxes in the presence of hydrogen or hydrogen-generating compounds
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts 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
    • B01J23/84—Catalysts 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 arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/85—Chromium, molybdenum or tungsten
    • B01J23/88—Molybdenum
    • B01J23/882—Molybdenum and cobalt
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts 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
    • B01J23/84—Catalysts 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 arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/85—Chromium, molybdenum or tungsten
    • B01J23/888—Tungsten
    • B01J23/8885—Tungsten containing also molybdenum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J33/00—Protection of catalysts, e.g. by coating

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Materials Engineering (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • General Chemical & Material Sciences (AREA)
  • Catalysts (AREA)
  • Production Of Liquid Hydrocarbon Mixture For Refining Petroleum (AREA)

Abstract

The invention discloses a paraffin hydrofining method. The method comprises the steps of mixing hydrogen and paraffin raw materials, crushing the hydrogen into micro bubbles with the diameter of 1 mu m-1 mm through a micro interface generator, and then entering a reactor to contact with a catalyst for hydrofining reaction; wherein the reactor comprises 3 catalyst beds, a protecting agent is filled in the first bed along the flowing direction of the reactant, a type I paraffin hydrofining catalyst is filled in the second bed, and a type II paraffin hydrofining catalyst is filled in the third bed; wherein the filling volumes of the protective agent, the type I paraffin hydrofining catalyst and the type II paraffin hydrofining catalyst respectively account for 2% -10%, 20% -40% and 50% -78% of the total volume of the reactor. The method solves the problem of shortened service life of the paraffin hydrofining catalyst caused by carbon deposition, prolongs the service life of the paraffin hydrofining catalyst and improves the operation period of a paraffin hydrogenation device.

Description

Paraffin hydrofining method
Technical Field
The invention relates to a paraffin hydrofining method, in particular to a method for preparing a catalyst and grading the catalyst used in the paraffin hydrofining process and a hydrogenation process thereof.
Background
Paraffin is an important petroleum processing product, and is a flaky or needle-shaped crystal obtained by solvent refining, solvent dewaxing or wax freezing crystallization, squeezing and dewaxing of a lubricating oil fraction obtained from crude oil distillation to prepare a cerate, and solvent deoiling and refining. Paraffin is widely applied to various fields of national economy such as food, medicine, precise instruments, daily chemical industry and the like.
The paraffin hydrofining process mainly comprises the hydrogenation of non-hydrocarbon compounds containing sulfur, nitrogen and oxygen, olefin hydrogenation and the hydrogenation saturation of polycyclic aromatic hydrocarbon. The paraffin hydrorefining generally adopts a fixed bed reactor, belongs to a typical trickle bed liquid phase reaction process, and has small reaction heat. The existing paraffin hydrofining process flow principle is different in flow, and the main difference is that the properties of raw materials, the used catalyst and the refining depth are different. Typical processes are single-stage and two-stage two-type hydrofining process streams.
CN103773499a discloses a hydrofining method of petroleum wax, which comprises the following steps: the petroleum wax raw material and hydrogen gas pass through a gas-liquid countercurrent hydrogenation reactor in a countercurrent mode, after the petroleum wax raw material and hydrogen gas contact and react with a non-noble metal hydrofining catalyst in the gas-liquid countercurrent hydrogenation reactor, gas phase is discharged from the top of the reactor for other purposes, liquid phase effluent directly enters a second hydrogenation reaction zone, sequentially passes through a hydrogenation protection reaction zone and a main hydrofining reaction zone, sequentially contacts with a hydrogenation protecting agent and a reduction type hydrofining catalyst in the second hydrogenation reaction zone for hydrogenation reaction, and after a hydrofining product is separated, the gas phase is circulated back to the gas-liquid countercurrent hydrogenation reactor, and the liquid phase is a refined petroleum wax product.
CN109988627a discloses a flexible paraffin hydrogenation process. The paraffin raw material enters a hydrofining reactor, and the material passing through the upper hydrofining catalyst bed layer is divided into two strands; one strand of material is pumped out of the hydrofining reactor from the middle of the bed layer and enters the hydroisomerization reactor for isomerization reaction; the other material continuously flows downwards through the hydrofining catalyst bed layer at the lower part; the obtained hydrofining reaction material and hydroisomerization reaction material are respectively subjected to gas-liquid separation and fractionation to obtain paraffin products with different specifications.
In the hydrogenation process of the conventional paraffin hydrofining catalyst, as the operation time of a hydrogenation device is prolonged, deposited carbon blocks pore channels to cover active sites, so that the utilization rate of active metals is reduced, and the operation period of the hydrogenation device is shortened. In the traditional fixed bed hydrogenation reaction device, the gas-liquid mass transfer phase boundary area is small, and the apparent reaction speed is slower. Therefore, the development of the paraffin hydrofining catalyst with long service life and carbon deposit resistance and the improvement of the technological process have great significance.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a paraffin hydrofining method to solve the problem of shortened service life of a paraffin hydrofining catalyst caused by deposition of carbon deposit, prolong the service life of the paraffin hydrofining catalyst and improve the operation cycle of a paraffin hydrogenation device.
The invention provides a paraffin hydrofining method, which comprises the steps of mixing hydrogen and paraffin raw materials, crushing the hydrogen into micro bubbles with the diameter of 1 mu m-1 mm through a micro interface generator, uniformly distributing the formed micro bubbles in the raw materials of the paraffin, and enabling a gas-liquid mixed phase to enter a reactor from the bottom of the reactor to contact with a catalyst for hydrofining reaction; the paraffin hydrofining reactor comprises 3 catalyst beds, wherein a protecting agent is filled in the first bed along the flowing direction of a reactant, a type I paraffin hydrofining catalyst is filled in the second bed, and a type II paraffin hydrofining catalyst is filled in the third bed; wherein the filling volumes of the protective agent, the type I paraffin hydrofining catalyst and the type II paraffin hydrofining catalyst respectively account for 2% -10%, 20% -40% and 50% -78% of the total volume of the reactor.
In the method of the invention, the paraffin raw material is the two-and three-line-reduced crude paraffin after solvent dewaxing and deoiling.
In the method, the reaction temperature is 230-310 ℃, the reaction pressure is 3.0-8.0 MPa, and the liquid hourly space velocity is 0.3-1.5 h -1 The hydrogen wax volume ratio is 100-500.
In the method of the present invention, the protecting agent may be selected from commercial protecting agents conventional in the art, or protecting agents prepared by other conventional methods, such as protecting agent series developed by Dalian petrochemical institute of China's petrochemical Co., ltd.
In the method of the invention, the type I paraffin hydrofining catalyst comprises a catalyst body composed of a carrier and an active component carried on the carrier, and a macroporous alumina layer is arranged on the outer surface of the catalyst body. The macropore alumina is 0.50cm higher than the pore volume of the catalyst body 3 Preferably 0.51 to 0.60% of the total weight of the catalyst per gram. The macroporous alumina layer contains at least one auxiliary agent of fluorine, phosphorus, silicon or boron, and the addition amount of the auxiliary agent is 0.5-20% of the mass of the alumina, preferably 1-16%, and more preferably 2-16% of the mass of the alumina.
In the method of the invention, in the type I paraffin hydrofining catalyst, the total acid amount of the macroporous alumina layer is 0.47-0.75 mmol/g.
In the method of the invention, in the type I paraffin hydrofining catalyst, the pore volume of the macroporous alumina layer is more than 0.90cm 3 And/g (mercury intrusion method), wherein the pore volume of pores with the pore diameter of more than 45nm accounts for 20-50% of the total pore volume, and can accommodate more carbon deposition. Because macroporous alumina added with the auxiliary agent has higher acidity, more carbon deposit can be deposited in the pore channels, and in order to prevent the pore channels from being blocked, the alumina membrane layer needs to have more pore channels with large aperture.
In the method of the invention, in the type I paraffin hydrofining catalyst, the thickness of the macroporous alumina layer is 1-500 mu m, preferably 50-200 mu m.
In the method of the invention, in the type I paraffin hydrofining catalyst, the characteristics of the catalyst body are as follows: pore volume of more than 0.35cm 3 The active metals of VIB group and VIII group are used as active metals, and the active metals are preferably molybdenum and cobalt, so that the catalystThe mass of the body is based on the weight, the content of molybdenum oxide is 4.0 to 30.0 percent, and the content of cobalt oxide is 1.0 to 10.0 percent.
In the method of the invention, the type II paraffin hydrofining catalyst comprises a catalyst body composed of a carrier and an active component carried on the carrier, and the outer surface of the catalyst body is provided with a macroporous alumina layer. The macropore alumina is 0.40cm higher than the pore volume of the catalyst body 3 Preferably 0.45 to 0.55 cm/g or more 3 /g。
In the method of the invention, in the II-type paraffin hydrofining catalyst, the pore volume of the macroporous alumina layer is more than 0.80cm 3 Preferably 0.85 to 0.95cm per gram (mercury intrusion) 3 And/g, the pore volume of the pores with the pore diameter of more than 30nm accounts for 20-60 percent, preferably 40-55 percent of the total pore volume, and can accommodate more carbon deposition.
In the method of the invention, in the type II paraffin hydrofining catalyst, the thickness of the macroporous alumina layer is 1-400 mu m, preferably 60-180 mu m.
In the method of the invention, in the type II paraffin hydrofining catalyst, the characteristics of the catalyst body are as follows: pore volume of more than 0.35cm 3 And/g, wherein the mass of the catalyst body is taken as a reference, the content of tungsten oxide is 2.0-25.0%, the content of molybdenum oxide is 2.0-20.0%, and the content of nickel oxide is 0.4-8.0%.
In the method of the invention, the preparation method of the type I paraffin hydrofining catalyst comprises the following steps:
a. impregnating an active metal into a paraffin hydrofining catalyst carrier to prepare a paraffin hydrofining catalyst as a catalyst body;
b. and c, adding the catalyst body obtained in the step a into macroporous pseudo-boehmite gel containing at least one auxiliary agent of fluorine, phosphorus, silicon or boron, stirring and soaking, wrapping the gel on the surface, taking out, drying and roasting to obtain the type I paraffin hydrofining catalyst.
In the step a, the catalyst carrier is selected from alumina or modified alumina, and the specific surface area of the catalyst carrier is 160-400 m 2 Per gram, the pore volume is 0.60-1.00 mL/g, and the average pore size is equalThe diameter is 7-16 nm.
In the step a, the active metal is preferably molybdenum or cobalt, and the content of molybdenum oxide is 4.0% -30.0%, preferably 6.0% -28.0%, more preferably 10.0% -26.0%, and the content of cobalt oxide is 1.0% -10.0%, preferably 2.0% -10.0%, more preferably 2.0% -8.0% based on the mass of the catalyst.
In step b, the catalyst body is preferably immersed in a binder solution before being added to the macroporous pseudo-boehmite gel. The mass content of the binder in the binder solution is 1% -80%, preferably 2% -25%. The adhesive solution consists of an adhesive and purified water. The adhesive can be at least one of starch, dextrin, polyvinyl alcohol or carboxymethyl cellulose.
Preferably, the catalyst body is soaked in the binder solution for 10 to 50 seconds, the excess binder solution is drained off, and the catalyst body is left to stand at room temperature for 15 to 60 minutes.
In the step b, the macroporous pseudo-boehmite gel has the following properties of being converted into macroporous alumina: pore volume of more than 0.90cm 3 And/g (mercury intrusion method), has a through pore, and the pore volume of pores with the pore diameter of more than 45nm accounts for 20-50% of the total pore volume, so that more carbon deposit can be accommodated. Wherein the macroporous pseudo-boehmite gel is converted into macroporous alumina by roasting at 450-650 ℃ for 3-6 hours. The macroporous pseudo-boehmite gel can be prepared by adopting an inorganic aluminum source as a raw material, adding an auxiliary agent and not adding a template agent, and performing hydrothermal treatment at 180-300 ℃ for 3-6 hours. The modified alumina added with the auxiliary agent has slightly higher surface acidity than the pure alumina, so that more carbon deposit is deposited in the alumina film layer to reduce the deposition in the catalyst body. The concentration of alumina in the macroporous pseudo-boehmite gel is 20 g/L-100 g/L, preferably 20 g/L-75 g/L.
In the step b, the catalyst particles are added into macroporous pseudo-boehmite gel and stirred, the soaking time is 10 s-20 min, the gel is taken out after the surface is wrapped, the gel is removed after the surface is centrifuged by a centrifuge, the superfluous gel on the surface is removed after the centrifugation time is 1-20 min, and then the catalyst particles are dried for 2-12 h at the temperature of 80-150 ℃. The thickness of the alumina film layer can be controlled by controlling the concentration, soaking time and centrifuging time of alumina in the macroporous pseudo-boehmite gel.
In the step b, the temperature programming is adopted for the roasting. The roasting conditions are as follows: the temperature rising rate is 1 ℃/min-3 ℃/min, the roasting temperature is 450-650 ℃ and the roasting time is 3-6 hours. After calcination, an alumina coating of 1 to 500. Mu.m, preferably 50 to 200. Mu.m, can be formed on the catalyst surface.
In the method of the invention, the preparation method of the type II paraffin hydrofining catalyst comprises the following steps:
(1) preparing a paraffin hydrofining catalyst as a catalyst body;
(2) adding the catalyst body obtained in the step (1) into macroporous pseudo-boehmite gel, stirring and soaking, wrapping the gel on the surface, taking out, drying and roasting to obtain the paraffin hydrofining catalyst.
The paraffin hydrofining catalyst in the step (1) has a pore volume of more than 0.35cm 3 The active metals in the catalyst are preferably tungsten, molybdenum and nickel, the content of tungsten oxide is 2.0-25.0 percent, the content of molybdenum oxide is 2.0-20.0 percent and the content of nickel oxide is 0.4-8.0 percent based on the mass of the catalyst body.
In step (2), the catalyst body is preferably immersed in a binder solution before being added to the macroporous pseudo-boehmite gel. The mass content of the binder in the binder solution is 1% -80%, preferably 2% -30%. The adhesive solution consists of an adhesive and purified water. The adhesive can be one or more of starch, dextrin, polyvinyl alcohol or carboxymethyl cellulose.
Preferably, the catalyst body is soaked in the binder solution for 10 to 50 seconds, the excess binder solution is drained off, and the catalyst body is left to stand at room temperature for 15 to 60 minutes.
In the step (2), the macroporous pseudo-boehmite gel has the following properties of being converted into macroporous alumina: pore volume of more than 0.80cm 3 /g (mercury intrusion method) with through holeThe pore volume of the pore with the aperture of more than 30nm is 20-60% of the total pore volume, and more carbon deposit can be accommodated. Wherein the macroporous pseudo-boehmite gel is converted into macroporous alumina by roasting at 450-650 ℃ for 3-6 hours. The macroporous pseudo-boehmite gel can be prepared by taking an inorganic aluminum source as a raw material, not adding a template agent, adjusting the pH value to 2.8-3.2, and carrying out hydrothermal treatment at 180-300 ℃ for 3-6 hours. The concentration of alumina in the macroporous pseudo-boehmite gel is 20 g/L-100 g/L, preferably 20 g/L-70 g/L.
In the step (2), the catalyst particles are added into macroporous pseudo-boehmite gel, stirred, soaked for 10 s-20 min, taken out after the gel is wrapped on the surface, centrifuged by a centrifuge to remove superfluous gel on the surface, and dried for 2-12 hours at 80-150 ℃. The thickness of the alumina film layer can be controlled by controlling the concentration, soaking time and centrifuging time of alumina in the macroporous pseudo-boehmite gel.
In the step (2), the temperature programming is adopted for the roasting. The temperature rising rate is 1 ℃/min-3 ℃/min, the roasting temperature is 450-650 ℃ and the roasting time is 3-6 hours. After calcination, an alumina coating of 1 to 400. Mu.m, preferably 60 to 180. Mu.m, can be formed on the catalyst surface.
Compared with the prior art, the invention has the following beneficial effects:
1. in the paraffin hydrofining method, hydrogen is crushed into micro bubbles with the diameter of micron by the micro interface generator before entering the reactor, and the micro bubbles have the advantages of good independence, uniform distribution and difficult combination, so that the contact probability between the hydrogen and the raw material wax is increased, the gas-liquid reaction is enhanced, and the mass transfer efficiency is improved.
2. The inventor finds that, in the paraffin hydrofining process, the protecting agent is sequentially filled in a specific proportion along the flowing direction of reactants by adopting the grading method of the catalyst, and the type I paraffin hydrofining catalyst and the type II paraffin hydrofining catalyst are sequentially filled in the specific proportion. Specifically, the surface of the type I paraffin hydrofining catalyst body is coated with macroporous alumina, and an auxiliary agent is added into the macroporous alumina, so that the catalyst has better desulfurization and nitrogen performance in the hydrogenation process, and more carbon deposit can be firstly deposited in alumina pore channels on the surface, and as the film layer is provided with penetrating pore channels, the carbon deposit but does not block the pore channels, wax can enter the catalyst body for hydrogenation reaction, the deposition of the carbon deposit in the catalyst body is reduced, and the carbon deposit resistance of the catalyst is improved; the II-type paraffin hydrofining catalyst has active metal of tungsten-molybdenum-nickel system, macroporous alumina is coated on the surface of the catalyst, the catalyst has good arene saturation performance, carbon deposit generated by reaction is firstly deposited in alumina pore channels on the surface in the hydrogenation process, and as the film layer is provided with penetrating pore channels, the carbon deposit but does not block the pore channels, wax can enter the catalyst body to carry out hydrogenation reaction, so that the deposition of carbon deposit in the catalyst body is reduced, the carbon deposit resistance of the catalyst is improved, and the service life of the catalyst is prolonged.
Drawings
FIG. 1 is a schematic illustration of a process flow of a paraffin hydrofining method of the present invention;
the reference numerals are explained as follows: i-new hydrogen, II-raw material wax, III-recycle hydrogen; 1-degasser, 2-heating furnace, 3-micro interface generator, 4-reactor, 5-hot high fraction and 6-cold high fraction.
Detailed Description
The technical scheme and effect of the present invention will be further described with reference to the following examples, but is not limited to the following examples.
The invention provides a process flow diagram of a paraffin hydrofining method (see figure 1). The method specifically comprises the following steps: raw material wax II is mixed with hydrogen after passing through a degassing tower 1, is heated by a heating furnace 2, is crushed into micro bubbles by a micro interface generator 3, and enters a reactor 4 from the bottom of the reactor as a gas-liquid mixed phase, and sequentially passes through a protective agent, a type I paraffin hydrofining catalyst and a type II paraffin hydrofining catalyst. The hydrogenation product comes out from the top of the reactor and enters a hot high fraction 5 and a cold high fraction 6 for separation.
In the invention, the pore volume, the pore diameter and the specific surface area of the external surface macroporous alumina related in the examples and the comparative examples are obtained by testing by adopting an instrument MicroActive AutoPore V9600 by mercury porosimetry, and the pore volume, the pore diameter and the specific surface area of the catalyst and the carrier are obtained by testing by adopting an ASAP-2420 physical adsorption instrument.
The method for measuring total acid content of macroporous alumina includes scraping alumina on the outer surface of the roasted catalyst, tabletting, introducing ammonia gas at a set temperature after nitrogen purging and temperature rising dehydration at normal temperature by using an instrument AUTOCHEM 2910 temperature programming adsorption instrument, adsorbing the sample until the ammonia gas is saturated, then purging the nitrogen gas to remove the ammonia gas physically adsorbed on the surface of the sample, and finally adsorbing NH on the sample under the temperature programming condition 3 The amount of acid was obtained by calculating the area of the desorption peak.
Example 1
The two-line reduction fraction prepared by reduced pressure distillation is prepared by taking a wax material (melting point 58.5 ℃, oil content 0.33wt%, color (Sai) -No. 7 and light stability No. 7-8) prepared by dewaxing and deoiling ketone benzene as a raw material wax, mixing with hydrogen after passing through a degassing tower 1, heating by a heating furnace 2, then passing through a micro-interface generator 3, crushing the hydrogen into micro-bubbles (diameter is 200-800 mu m) and then entering a reactor 4, wherein the raw material wax is shown in the figure 1. The paraffin hydrogenation reactor is filled with 5% of protective agent, 35% of type I paraffin hydrofining catalyst and 60% of type II paraffin hydrofining catalyst in sequence. At a reaction temperature of 255 ℃, a reaction pressure of 5.0MPa and a liquid hourly space velocity of 1.0h- 1 And carrying out paraffin hydrogenation under the process condition that the hydrogen wax volume ratio is 500:1.
Preparation of type I paraffin hydrofining catalyst:
a, taking a catalyst alumina carrier (the specific surface area of the carrier is 336m 2 Per gram, pore volume of 0.72mL/g, average pore diameter of 9.7 nm) of the impregnated molybdenum cobalt solution, the content of molybdenum oxide on the impregnated catalyst was 23.7%, and the content of cobalt oxide was 4.7%.
b, preparing an adhesive solution: dissolving 25g of starch in 500 g of purified water under heating and stirring, and uniformly stirring and dissolving;
c, preparing macroporous pseudo-boehmite gel: 50g of aluminum sulfate, 5g of silica sol (30% by weight of silica) are weighed and hydrothermally treated at 180℃for 4 hours. The concentration of alumina in the macroporous pseudo-boehmite was 25g/L.
d immersing the catalyst particles in the step b after drying in the binder in the step b for 15 seconds, taking out, draining excessive binder solution, and standing at room temperature for 25 minutes.
And e, adding the catalyst particles obtained in the step d into the macroporous pseudo-boehmite gel prepared in the step c, stirring for 2min, taking out after the gel is wrapped on the surface, centrifuging for 2min by a high-speed centrifuge, and drying at 120 ℃ for 5 h.
f, roasting: roasting for 4 hours at a temperature rising rate of 1 ℃/min to 550 ℃ by adopting a temperature programming mode to obtain the type I paraffin hydrofining catalyst, wherein the thickness of the macroporous alumina film layer is 122 mu m, and the pore volume is 0.95cm 3 And/g, wherein the pore volume occupied by pores with the pore diameter of more than 45nm is 38% of the total pore volume. The pore volume of the macroporous alumina membrane layer is 0.53cm higher than that of the paraffin hydrofining catalyst body 3 The total acid amount per gram of macroporous alumina was 0.541mmol/g.
Preparation of type II paraffin hydrofining catalyst:
(1) 100g of paraffin hydrofining catalyst with a pore volume of 0.40cm was prepared 3 Per gram, the content of tungsten oxide in the catalyst is 13.5 percent, the content of molybdenum oxide is 15.0 percent, and the content of nickel oxide is 4.5 percent
(2) Preparing an adhesive solution: dissolving 25g of starch in 500 g of purified water under the condition of heating and stirring, and uniformly stirring and dissolving;
(3) Preparing macroporous pseudo-boehmite gel: 50g of aluminum sulfate was weighed, the pH value was adjusted to 3.0, and the mixture was subjected to hydrothermal treatment at 180℃for 3 hours. The concentration of alumina in the macroporous pseudo-boehmite is 28g/L.
(4) Immersing the dried catalyst particles in the step (1) in the adhesive in the step (2) for 15 seconds, taking out, draining excessive adhesive solution, and standing for 30 minutes at room temperature.
(5) Adding the catalyst particles obtained in the step (4) into the macroporous pseudo-boehmite gel obtained in the step (3), stirring for 2min, taking out after the gel is wrapped on the surface, centrifuging for 2min by a high-speed centrifuge, and drying at 120 ℃ for 5 h.
(6) Roasting: roasting for 4 hours at a temperature rising rate of 1 ℃/min to 500 ℃ by adopting a temperature programming mode to obtain the type II paraffin hydrofining catalyst, wherein the thickness of the macroporous alumina film layer is 124 mu m, and the pore volume is 0.86cm 3 And/g, wherein the pore volume occupied by pores with the pore diameter of more than 30nm is 43% of the total pore volume. The pore volume of the macroporous alumina membrane layer is 0.46cm higher than that of the paraffin hydrofining catalyst body 3 /g。
Example 2
The hydrogenation reaction was carried out under process conditions at a reaction temperature of 265℃as in example 1. The paraffin hydrogenation reactor is filled with 3% of protective agent, 37% of type I paraffin hydrofining catalyst and 60% of type II paraffin hydrofining catalyst in sequence.
Preparation of type I paraffin hydrofining catalyst:
the difference from example 1 is that 6g boric acid is added in step c, the concentration of alumina in the macroporous pseudo-boehmite is adjusted to 35g/L, the thickness of the macroporous alumina film layer is 132 μm, and the pore volume is 0.93cm 3 And/g, wherein the pore volume of pores with the pore diameter of more than 45nm accounts for 36% of the total pore volume. The pore volume of the macroporous alumina membrane layer is 0.51cm higher than that of the paraffin hydrofining catalyst body 3 The total acid amount per gram of macroporous alumina was 0.550mmol/g.
Preparation of type II paraffin hydrofining catalyst:
the difference from example 1 is that in step (3) the pH was adjusted to 2.9 and the hydrothermal treatment was carried out at 180℃for 3.5 hours. The concentration of alumina in the macroporous pseudo-boehmite is 50g/L, thus obtaining the paraffin hydrofining catalyst coated with alumina, the thickness of the macroporous alumina film layer is 147 mu m, and the pore volume is 0.89cm 3 And/g, wherein the pore volume occupied by pores with the pore diameter of more than 30nm is 47% of the total pore volume. The macropore alumina is 0.49cm higher than the pore volume of the catalyst body 3 /g。
Example 3
The same as in example 1, except that 10% of the protecting agent, 20% of the type I paraffin hydrofining catalyst and 70% of the type II paraffin hydrofining catalyst were sequentially charged into the paraffin hydrogenation reactor.
Preparation of type I paraffin hydrofining catalyst:
immersing the catalyst particles in macroporous pseudo-boehmite gel in step e, stirring, coating the gel on the surface, taking out, centrifuging for 7min by a high-speed centrifuge, drying at 110 ℃ for 6 hours, heating to 520 ℃ at a heating rate of 3 ℃/min, and roasting for 5 hours to obtain the type I paraffin hydrofining catalyst, wherein the thickness of the macroporous alumina film layer is 80 mu m, and the pore volume is 0.92cm 3 And/g, wherein the pore volume of pores with the pore diameter of more than 45nm accounts for 35% of the total pore volume. The total acid amount of the macroporous alumina was 0.559mmol/g.
Preparation of type II paraffin hydrofining catalyst:
adjusting the concentration of alumina in the macroporous pseudo-boehmite in the step (3) to be 50g/L, immersing the catalyst particles in the macroporous pseudo-boehmite gel in the step (3) in the step (5) at the same time, stirring for 10min, wrapping the gel on the surface, taking out, centrifuging for 7min by a high-speed centrifuge, and obtaining the type II paraffin hydrofining catalyst, wherein the thickness of a macroporous alumina film layer is 138 mu m, and the pore volume is 0.87cm 3 And/g, wherein the pore volume occupied by pores with the pore diameter of more than 30nm is 44% of the total pore volume. The macropore alumina is 0.47cm higher than the pore volume of the catalyst body 3 /g。
Example 4
As in example 1, the reaction conditions were: the reaction temperature is 260 ℃, the reaction pressure is 4.5MPa, and the volume space velocity is 1.0h- 1 And carrying out paraffin hydrogenation under the process condition that the hydrogen wax volume ratio is 500:1.
The same example 1, the preparation of the type I catalyst only comprises steps (a), (c), (e) and (f), and the steps (b) and (d) are not needed, so that the paraffin hydrofining catalyst coated with alumina is obtained, the thickness of a macroporous alumina film layer is 27 mu m, and other properties are the same as example 1.
The same example 1, the preparation of the II type catalyst only comprises steps (1), (3), (5) and (6), and the steps (2) and (4) are not needed, so that the paraffin hydrofining catalyst coated with alumina is obtained, the thickness of a macroporous alumina film layer is 38 mu m, and other properties are the same as example 1.
Comparative example 1
The difference is that this example isThe type I paraffin hydrorefining catalyst used was the catalyst obtained in step a of example 1, i.e., the specific surface area of the carrier was 336m 2 Per g, pore volume of 0.72mL/g and average pore diameter of 9.7nm. The molybdenum cobalt solution is impregnated, the content of molybdenum oxide on the catalyst after impregnation is 23.7 percent, and the content of cobalt oxide is 4.7 percent.
The difference from example 1 is that: the II-type paraffin hydrofining catalyst adopts the paraffin hydrofining catalyst prepared in the step (1), namely the pore volume of the catalyst is 0.40cm 3 The content of tungsten oxide in the catalyst is 13.5 percent, the content of molybdenum oxide is 15.0 percent, and the content of nickel oxide is 4.5 percent.
Comparative example 2
The same as in example 1, except that the commercial paraffin hydrofining catalyst was directly used instead of the type I and type II paraffin hydrofining catalysts in this example, the pore volume of the catalyst was 0.39cm 3 The content of tungsten oxide in the catalyst was 28.5% and the content of nickel oxide was 5.5%.
Comparative example 3
The difference is that no auxiliary agent is added in the preparation of c macroporous pseudo-boehmite gel in the preparation process of the type I paraffin hydrofining catalyst in the example 1. The thickness of the macroporous alumina membrane layer in the prepared catalyst is 120 mu m, and the pore volume is 0.90cm 3 And/g, wherein the pore volume of the pores with the pore diameter of more than 45nm accounts for 31 percent of the total pore volume. The pore volume of the macroporous alumina membrane layer is 0.48cm higher than that of the paraffin hydrofining catalyst body 3 The total acid amount per gram of macroporous alumina was 0.431mmol/g.
In this example, the type II paraffin hydrofining catalyst was prepared in step (3) by an aluminum sulfate method using a common parallel flow method, and 2L of an aqueous sodium metaaluminate solution (Al 2 O 3 A concentration of 15g/100 mL) and 3L of an aqueous solution of aluminum sulfate (in terms of Al 2 O 3 The concentration is 8g/100 mL), the gel forming temperature is 60 ℃, the gel forming pH value is 7.7, and the obtained alumina film layer does not have penetrating pore channels. Finally obtaining pseudo-boehmite gel, and preparing the type II paraffin hydrofining catalyst. The thickness of the alumina film layer is 127 mu m, and the pore volume is 0.67cm 3 Per g, pore diameter > 30nmThe pore volume is 15% of the total pore volume, and the macroporous alumina is 0.27cm higher than the pore volume of the catalyst body 3 /g。
Comparative example 4
The procedure is as in example 1, except that the loading ratio of the protecting agent, type I paraffin hydrofining catalyst and type II paraffin hydrofining catalyst is the same in this example.
Comparative example 5
The difference from example 1 is that hydrogen is introduced directly into the reactor to react with the feed wax.
Table 1 Properties of the products after 2000h of the hydrofinishing reaction for each example
Table 1 Properties of the products after 2000h of the hydrofinishing reaction (follow-up)
As can be seen from Table 1, after 2000 hours of hydrofining at a lower reaction pressure, the performance of the hydrogenated product obtained by the method is better than that of the comparative example, and the hydrogenated product still has better hydrogenation performance, thereby providing guarantee for prolonging the running period of the device.

Claims (10)

1. A method for hydrofining paraffin includes such steps as mixing hydrogen with paraffin raw material, breaking hydrogen into 1-1 mm microbubbles by micro-interface generator, uniformly distributing the microbubbles in raw material wax, and contact between hydrogen and catalyst; the paraffin hydrofining reactor comprises 3 catalyst beds, wherein a protecting agent is filled in the first bed along the flowing direction of a reactant, a type I paraffin hydrofining catalyst is filled in the second bed, and a type II paraffin hydrofining catalyst is filled in the third bed; wherein the filling volumes of the protective agent, the type I paraffin hydrofining catalyst and the type II paraffin hydrofining catalyst respectively account for 2% -10%, 20% -40% and 50% -78% of the total volume of the reactor.
2. The method for hydrorefining paraffin according to claim 1, wherein the reaction temperature is 230-310 ℃, the reaction pressure is 3.0-8.0 MPa, and the liquid hourly space velocity is 0.3-1.5 h -1 The hydrogen wax volume ratio is 100-500.
3. The method for hydrofining paraffin wax according to claim 1, wherein the type i paraffin wax hydrofining catalyst comprises a catalyst body composed of a carrier and an active component carried on the carrier, and a macroporous alumina layer is provided on the outer surface of the catalyst body; the macropore alumina is 0.50cm higher than the pore volume of the catalyst body 3 Preferably 0.51 to 0.60cm per gram 3 /g。
4. A paraffin hydrofining method as defined in claim 3, wherein in the type i paraffin hydrofining catalyst, the macroporous alumina layer contains at least one auxiliary agent of fluorine, phosphorus, silicon or boron, and the addition amount of the auxiliary agent is 0.5% -20%, preferably 1% -16%, more preferably 2% -16% of the mass of alumina in terms of element.
5. A paraffin hydrofining method as defined in claim 3, wherein in said type i paraffin hydrofining catalyst, said macroporous alumina layer has a total acid amount of 0.47 to 0.75mmol/g.
6. A paraffin hydrofining method as defined in claim 3, wherein in said type i paraffin hydrofining catalyst, said macroporous alumina layer has a pore volume of more than 0.90cm 3 And/g, wherein the pore volume of the pores with the pore diameter of more than 45nm accounts for 20-50% of the total pore volume.
7. A paraffin hydrofining method as claimed in claim 3, wherein in said type i paraffin hydrofining catalyst, the thickness of said macroporous alumina layer is 1 to 500 μm, preferably 50 to 200 μm.
8. The paraffin hydrofining method as defined in claim 1, wherein the type ii paraffin hydrofining catalyst comprises a catalyst body composed of a carrier and an active component carried on the carrier, and a macroporous alumina layer is provided on the outer surface of the catalyst body; the macropore alumina is 0.40cm higher than the pore volume of the catalyst body 3 Preferably 0.45 to 0.55 cm/g or more 3 /g。
9. The process for the hydrofining of paraffin wax according to claim 8, wherein in the type II paraffin wax hydrofining catalyst, the macroporous alumina layer has a pore volume of more than 0.80cm 3 Preferably 0.85 to 0.95cm 3 And/g, the pore volume of the pores with the pore diameter of more than 30nm accounts for 20-60 percent of the total pore volume, and preferably 40-55 percent.
10. The paraffin hydrofining method according to claim 8, wherein in the type ii paraffin hydrofining catalyst, the thickness of the macroporous alumina layer is 1 to 400 μm, preferably 60 to 180 μm.
CN202210456905.4A 2022-04-27 2022-04-27 Paraffin hydrofining method Pending CN117004438A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210456905.4A CN117004438A (en) 2022-04-27 2022-04-27 Paraffin hydrofining method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210456905.4A CN117004438A (en) 2022-04-27 2022-04-27 Paraffin hydrofining method

Publications (1)

Publication Number Publication Date
CN117004438A true CN117004438A (en) 2023-11-07

Family

ID=88560489

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210456905.4A Pending CN117004438A (en) 2022-04-27 2022-04-27 Paraffin hydrofining method

Country Status (1)

Country Link
CN (1) CN117004438A (en)

Similar Documents

Publication Publication Date Title
US4263127A (en) White oil process
KR101622925B1 (en) Hydrogenation isomerization catalyst, method for producing same, method for dewaxing hydrocarbon oil, and method for producing lubricant base oil
CN1231559C (en) Catalytic reforming process for producing aromatic hydrocarbon-rich products using three catalyst zone
CN109261201B (en) Core-shell type hydrogenation catalyst and preparation method thereof
CN110270367B (en) In-situ packaged noble metal Pd molecular sieve catalyst and preparation method and application thereof
CN100384730C (en) Improved zeolites and molecular sieves and the use thereof
WO2011129534A2 (en) Catalyst for a hydrogenation dewaxing process and method for manufacturing same
CN113881457B (en) Method for treating aromatic hydrocarbon-rich distillate
CN106669811A (en) MCM-22/ZSM-22 composite molecular sieve catalyst and its preparation method and application
CN101450313A (en) Preparation method of macropore heavy-oil hydrogenation catalyst
CN117004438A (en) Paraffin hydrofining method
CN112439433B (en) Catalyst with hydrogenation and dimerization functions and preparation method and application thereof
CN112625773B (en) Preparation method of transformer oil base oil
CN1195828C (en) Process for hydrorefining basic oil lubricating oil
US4961836A (en) Synthesis of transition metal alumino-silicate IOZ-5 and use of it for hydrocarbon conversion
CN112779050A (en) Processing method of poor-quality catalytic diesel oil
CN112275310A (en) Heavy aromatic hydrocarbon lightening catalyst based on VIB and VIII group composite metal elements and preparation method and application thereof
US4755279A (en) Process for the manufacture of lubricating oils
CN1331993C (en) Pretreatment method of lubricating oil hydrogenation isomeric dewax raw material
KR20080046686A (en) A process for the selective hydrogenation of olefins
CN108262067A (en) A kind of hydrogenation catalyst and preparation method thereof
CN101410181B (en) Hydrocracking catalyst, and method for production of fuel base material
CN107344119B (en) Hydrocracking catalyst carrier and preparation method thereof
CN112745920A (en) Hydrocracking method for producing high-octane gasoline
JP6009196B2 (en) Manufacturing method of base oil for lubricating oil

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination