WO2009035234A2 - Process for the chlorine by oxidation of hydrogen chloride - Google Patents

Process for the chlorine by oxidation of hydrogen chloride Download PDF

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Publication number
WO2009035234A2
WO2009035234A2 PCT/KR2008/005241 KR2008005241W WO2009035234A2 WO 2009035234 A2 WO2009035234 A2 WO 2009035234A2 KR 2008005241 W KR2008005241 W KR 2008005241W WO 2009035234 A2 WO2009035234 A2 WO 2009035234A2
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WIPO (PCT)
Prior art keywords
cerium
catalyst
hydrogen chloride
compound
chlorine
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PCT/KR2008/005241
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French (fr)
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WO2009035234A3 (en
Inventor
Gwanghyun Lee
Sang Wook Lee
Inwan Sohn
Young Chul Kwon
Junhye Song
Chang-Sub Son
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Hanwha Chemical Corperation
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Publication of WO2009035234A2 publication Critical patent/WO2009035234A2/en
Publication of WO2009035234A3 publication Critical patent/WO2009035234A3/en

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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B7/00—Halogens; Halogen acids
    • C01B7/01—Chlorine; Hydrogen chloride
    • C01B7/03—Preparation from chlorides
    • C01B7/04—Preparation of chlorine from hydrogen chloride
    • 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
    • B01J23/10—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of rare earths
    • 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
    • B01J35/00—Catalysts, in general, characterised by their form or physical properties
    • B01J35/40—Catalysts, in general, characterised by their form or physical properties characterised by dimensions, e.g. grain size
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/64—Nanometer sized, i.e. from 1-100 nanometer

Definitions

  • the present invention relates to a method for preparing chlorine, in which hydrogen chloride is decomposed to produce chlorine, precisely hydrogen chloride is reacted with oxygen containing gas in the presence of a cerium catalyst to produce chlorine .
  • Chlorine is widely used in the production of various compounds and is in increasing demand.
  • hydrochloric acid (liquid phase) or hydrogen chloride (gas phase) the byproducts generated during chlorination, cannot find its usability, and thus is discarded, which requires high costs and labors. And the amount of such byproduct is gradually increasing.
  • most of hydrochloric acid and hydrogen chloride are prepared in the phase of aqueous solution (20% or 35% hydrochloric acid) for sale or are discarded after being neutralized.
  • the above treatment method not only causes economical damage but also causes environmental problems. Therefore, a method for converting hydrochloric acid generated massively as a byproduct in chlorination industry into chlorine can be an efficient and positive way to reduce hydrochloric acid treatment costs and to cope with environmental problems because the conversion of hydrochloric acid into chlorine does not break the balance between supply and demand of sodium hydroxide generated during electrolysis and only increases the production of chlorine.
  • Deacon Process is a kind of contact oxidation using CuCl 2 as a catalyst, which requires high reaction temperature of 450 ⁇ 500 ° C. So, at this high temperature, a catalyst is easily decomposed and it is difficult to design a device specifically to treat corrosive substances at that high temperature. Thus, this process could not be commercialized. But, based on this process, different catalytic oxidation methods have been tried as follows.
  • MT-Chlor process is a method for preparing chlorine using chrome-silica fluid-bed catalyst.
  • Kel-Chlor process is a method for preparing chlorine by non-contact oxidation developed by Kellog, in which nitrogen oxide is used as a catalyst and sulfuric acid is used as a circulatory catalyst.
  • Shell-Chlor process is a modified contact oxidation method using a copper oxide catalyst which has been improved from the original contact oxidation method developed by Deacon in 1868 and established by Shell in 1960 which enables lower temperature reaction (350 ⁇ 400°C) .
  • a chrome based catalyst using chrome oxide has been proposed as an alternative for the said copper or iron based catalyst (British Patent No. 676667) . Even if this catalyst provides high hydrogen chloride conversion rate (60-75%) , the chrome based catalyst is also reacted at high temperature of at least 400 ° C. So, short life time of the catalyst is still a problem with this chrome based catalyst.
  • Dichrome trioxide catalyst generally represented as MT- Chlor catalyst has been proposed (Japanese Patent Publication Nos. 62-153103, 62-191403, 62-241805, and 62-275001, Korean Patent No. 10-0032752) . And also cerium chloride containing dichrome trioxide catalyst was proposed (Korean Patent Publication No. 1999-0000001) . But the activity and short life time of the catalyst was still a problem. In addition, the process of producing this catalyst was very complicated.
  • the present invention provides a method for preparing chlorine from hydrogen chloride, in which cerium oxide having excellent stability and durability and far less expensive than the said platinum based catalyst is used as a catalyst for oxidation.
  • the method of the present invention is characterized by using a cerium compound as a catalyst for the production of chlorine by oxidizing hydrogen chloride with oxygen containing gas .
  • the cerium compound herein is preferably cerium oxide, cerium complex oxide or a mixture thereof, and the cerium compound is preferably selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof .
  • the cerium compound is preferably an oxide of a compound selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof.
  • the cerium compound is more preferably cerium oxide.
  • the catalyst above is preferably prepared by loading the cerium compound in a support or by oxidation of the cerium compound loaded in a support .
  • the content of the cerium compound in the support is preferably 1-10 weight%.
  • the cerium compound is preferably in the shape of particle of 100 ran - 100 ⁇ m in size.
  • the cerium compound is used as a main catalyst and one or more metals selected from platinum group elements or one or more metal compounds of metals selected from platinum group elements as a cocatalyst.
  • the preferable content of the cocatalyst in the catalyst is 1-50 weight%.
  • the method of the present invention is characterized by preparing chlorine at 250-400°C in the presence of the cerium based catalyst (a catalyst using the said cerium compound) .
  • the cerium based catalyst used for the preparation of chlorine in this invention has lower reaction temperature of up to 400 ° C, has high activity, and has high stability, so that it maintains catalytic activity for a long time of reaction and thus has a merit for economy.
  • Figure 1 is a graph illustrating the result of X-ray fraction with the cerium oxide before and after the reaction of Example 8.
  • the key technique of the method of the present invention is to produce chlorine by oxidizing hydrogen chloride with oxygen containing gas in the presence of a cerium compound.
  • the method of the present invention is to commercialize the process of chlorine production based on gas phase reaction of hydrogen chloride in a catalytic reactor.
  • the present invention relates to a catalyst that is capable of preventing the reduction of catalytic activity by exothermic reaction and thus is economical.
  • the reaction between hydrogen chloride and oxygen in a catalytic reactor is represented by the following reaction formula 1.
  • reaction formula 1 theoretical ratio of hydrogen chloride to oxygen(0 2 ) is 4:1 and the reaction is exothermic reaction. So, it is economically advantageous and more effective in preventing damage of a catalyst to generate chlorine at a temperature as low as possible as long as the catalyst maintains its catalytic activity.
  • the cerium compound herein is preferably cerium oxide, cerium complex oxide or a mixture thereof , and the cerium compound is preferably selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof .
  • the cerium compound is preferably an oxide of a compound selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof.
  • the cerium compound is more preferably cerium oxide.
  • the cerium compound of the present invention can be prepared by the conventional method. Or a commercial cerium compound can be used.
  • the method for preparing cerium complex oxide is exemplified by coprecipitation method, dispersion method (dispersion and heat treatment) and impregnation method.
  • the cerium compound is prepared as particles having the size of 100 nm - 100 jM or as granules composed of the particles.
  • This particle type or granule type cerium compound can be filled in a reactor or can be loaded in a support .
  • the catalyst is loaded in a support.
  • the cerium compound of the present invention is not cerium oxide, the cerium compound is loaded in a support first and then oxidized.
  • cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide or a mixture thereof is loaded in a support and oxidized in the presence of oxygen at 450-1300 ° C to produce a cerium oxide catalyst.
  • the support herein is any support used for the commercial reaction of chlorine preparation from hydrogen chloride by gas phase reaction, which is preferably exemplified by titanium oxide, alumina, silica, zirconium oxide, zeolite, titanium complex oxide, zirconium complex oxide, aluminum complex oxide and silicon complex oxide.
  • the support herein preferably has micro-pores. To load a cerium compound into a support, impregnation method or equilibrium absorption method can be used.
  • the content of the cerium compound loaded in a support is preferably 1 - 10 weight% by the support.
  • the above range of the content is preferable condition for a catalyst to maintain the catalytic activity with minimizing the reduction of specific surface area of the support.
  • the cerium compound is preferably in the shape of particle of 100 nm - 100 ⁇ m in size. This sized particle is advantageous for maintaining stability at high temperature, for preventing over-heating by exothermic reaction to produce chlorine and for obtaining high conversion rate (high chlorine yield) by maximizing surface area of the catalyst.
  • the cerium compound of 100 nm - 100 ⁇ m in size can be loaded in a support or fills a reaction tube as a catalyst.
  • the size of the cerium compound particle can be regulated by pulverizing a commercial cerium compound and filtering thereof, or by optimizing heat -treatment temperature and heat- treatment time after synthesis, or by optimizing synthesis condition itself .
  • the cerium compound is used as a main catalyst and one or more metals selected from platinum group elements or one or more metal compounds of metals selected from platinum group elements as a cocatalyst.
  • the cocatalyst herein is added in order to increase the activity of the cerium compound and preferable content of such cocatalyst is 1-50 weight% by the total weight of the catalyst.
  • the method of the present invention is characterized by lower temperature reaction of at 250-400 ° C, more preferably at 300-350 ° C, in the presence of the cerium based catalyst (cerium compound catalyst as mentioned above) to produce chlorine.
  • a glass reactor having 1" of inside diameter was used. Hydrogen chloride gas and oxygen gas, the reactants, were added to the reactor at the ratio of 1:1. Flow rates of the reactants were 25 ml/min respectively.
  • the reactor was filled with cerium oxide (Hanwha Chemical Co., Cat. #: CED30S) of 10 ⁇ m in mean diameter at the density of 0.4 g/cm 3 .
  • the reactor was 20 cm long and the temperature of the reactor was maintained as 350°C .
  • Conversion Rate (%) (amount of chlorine gas generated*2) / (amount of hydrogen chloride before the reaction) *100
  • a glass reactor (inside diameter: 1", length: 100 cm) was filled with the cerium compound of Example 1 at the density of 0.4g/cm 3 .
  • Hydrogen chloride gas and oxygen gas, the reactants, were provided to the reactor at the molar ratio of 1:2.
  • Flow rate of the hydrogen chloride gas: oxygen gas was 25:50 ml/min.
  • temperature of the reactor was maintained at 350 ° C.
  • Example 5 Experiments were performed by the same manner as described in Example 5 except that the flow rate of hydrogen chloride gas: oxygen gas was adjusted to 17:34 ml/min and temperature of the reactor was maintained at 300 ° C (Example 6) and the flow rate of hydrogen chloride gas: oxygen gas was adjusted to 17:34 ml/min and temperature of the reactor was maintained at 350 ° C (Example 7) . From 2 hours after the reaction was started, in Examples 5 - 7, generated gas was captured and analyzed by Orsat method and the results are shown in Table 2.
  • Reaction was induced by the same manner as described in Example 5 except that the temperature of the reactor was maintained at 400 ° C.
  • the catalytic activity was examined by analyzing reaction gas (conversion rate for the first 2 hours: 53.5%, conversion rate for 100 hours: 52.7%) .
  • Non-used catalyst and used catalyst after 100 hours of the reaction were investigated by X-ray fraction and the results are shown in Figure 1. As shown in Figure 1 , there was no change in the structure of the catalyst used for 100 hours of the reaction at the high temperature of 400 ° C.
  • Examples 1 - 8 pure cerium compound alone was used as a catalyst.
  • the method for preparing chlorine using the cerium based catalyst of the present invention was confirmed to have economical advantages because it gives high conversion rate of at least 60% at up to 400 ° C ; maintains catalytic activity at even high temperature of 400°C, maintains stable structure, activity and stability at high-temperature without platinum group elements.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
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Abstract

The present invention relates to a method for preparing chlorine by decomposing hydrogen chloride, in which hydrogen chloride is reacted with oxygen containing gas in the presence of a cerium based catalyst at comparatively low temperature of up to 400°C to produce chlorine. The cerium based catalyst of the present invention maintains its catalytic activity for a long time, compared with other catalysts prepared by the conventional processes, has excellent stability at high temperature, and has high economical efficiency, so that it paves the way to the development of an economically excellent oxidative decomposition process to produce chlorine from hydrogen chloride.

Description

[DESCRIPTION!
[invention Title]
PROCESS FOR THE CHLORINE BY OXIDATION OF HYDROGEN CHLORIDE
[Technical Field]
The present invention relates to a method for preparing chlorine, in which hydrogen chloride is decomposed to produce chlorine, precisely hydrogen chloride is reacted with oxygen containing gas in the presence of a cerium catalyst to produce chlorine .
[Background Art]
Chlorine is widely used in the production of various compounds and is in increasing demand. However, hydrochloric acid (liquid phase) or hydrogen chloride (gas phase) , the byproducts generated during chlorination, cannot find its usability, and thus is discarded, which requires high costs and labors. And the amount of such byproduct is gradually increasing. In Korea, except the case of preparing VCM by reacting hydrogen chloride with ethylene in an oxychlorination reactor, most of hydrochloric acid and hydrogen chloride are prepared in the phase of aqueous solution (20% or 35% hydrochloric acid) for sale or are discarded after being neutralized.
The above treatment method not only causes economical damage but also causes environmental problems. Therefore, a method for converting hydrochloric acid generated massively as a byproduct in chlorination industry into chlorine can be an efficient and positive way to reduce hydrochloric acid treatment costs and to cope with environmental problems because the conversion of hydrochloric acid into chlorine does not break the balance between supply and demand of sodium hydroxide generated during electrolysis and only increases the production of chlorine.
It has long been tried to recover chlorine from hydrogen chloride produced as a byproduct to solve the unbalance between the production of chlorine and the generation of hydrogen chloride. Deacon introduced a method to produce chlorine from hydrogen chloride by catalytic oxidation. Since then, methods modified from the catalytic oxidation have been tried and some of them made progress to be practical . The key point of the method producing chlorine from hydrogen chloride by oxidation is the selection of a catalyst and the success of this method depends on the efficiency of a selected catalyst.
The first method to produce chlorine from hydrogen chloride by oxidation, "Deacon Process" was named after the inventor. Deacon process is a kind of contact oxidation using CuCl2 as a catalyst, which requires high reaction temperature of 450~500°C. So, at this high temperature, a catalyst is easily decomposed and it is difficult to design a device specifically to treat corrosive substances at that high temperature. Thus, this process could not be commercialized. But, based on this process, different catalytic oxidation methods have been tried as follows. MT-Chlor process is a method for preparing chlorine using chrome-silica fluid-bed catalyst. Kel-Chlor process is a method for preparing chlorine by non-contact oxidation developed by Kellog, in which nitrogen oxide is used as a catalyst and sulfuric acid is used as a circulatory catalyst. Shell-Chlor process is a modified contact oxidation method using a copper oxide catalyst which has been improved from the original contact oxidation method developed by Deacon in 1868 and established by Shell in 1960 which enables lower temperature reaction (350~400°C) .
To improve the copper based catalyst, so called Deacon catalyst, various catalysts and different processes have been reported (US Patent No. 2418930, US Patent No. 2418931, US Patent No. 4119705, Japanese Patent Publication No. 53-125989, etc) . However, reaction temperatures for the processes are all at least 400 "C . An iron based catalyst was once proposed (US Patent No. 2577808) , which has also a problem of temperature limitation to at least 400°C making the catalyst life short.
A chrome based catalyst using chrome oxide has been proposed as an alternative for the said copper or iron based catalyst (British Patent No. 676667) . Even if this catalyst provides high hydrogen chloride conversion rate (60-75%) , the chrome based catalyst is also reacted at high temperature of at least 400°C. So, short life time of the catalyst is still a problem with this chrome based catalyst.
Dichrome trioxide catalyst generally represented as MT- Chlor catalyst has been proposed (Japanese Patent Publication Nos. 62-153103, 62-191403, 62-241805, and 62-275001, Korean Patent No. 10-0032752) . And also cerium chloride containing dichrome trioxide catalyst was proposed (Korean Patent Publication No. 1999-0000001) . But the activity and short life time of the catalyst was still a problem. In addition, the process of producing this catalyst was very complicated.
There is another method for preparing chlorine by hydrogen chloride oxidation, which has been developed by Sumitomo Co. and commercialized (Japanese Patent Publication Nos. 95-119866 and 95-157959, Korean Patent No. 10-0424502) . This method is characterized by lower reaction temperature using smaller amount of highly active ruthenium oxide catalyst for producing chlorine. The key technique of this method is to use ruthenium compounds (ruthenium oxides or ruthenium complex oxides) as a catalyst for oxidation. Precisely, by taking advantage of high activity of ruthenium, oxidation is induced at lower temperature of 300 "C with smaller amount of the catalyst.
In the meantime, Mitsui Toatus Chemical Inc reported the reaction process and reactor comprising two different reaction areas and heat exchange system using copper chloride, potassium chloride, chromium oxide or ruthenium oxide as a catalyst with suggesting the possibility of commercialization (US Patent Publication Nos . 94-278804, 95-226090 and 95- 228749, Korean Patent Publication No. 1996-0016957, PCT No. 88-00171, Korean Patent Publication No. 1988-0701212) . However, to lower reaction temperature and to commercialize, highly expensive ruthenium, the platinum group element, has to be used. Moreover the stability at high temperature is still in doubt and the increase of chlorine production cost resulted from the expensive catalyst make commercialization difficult.
Most of catalysts used in the conventional methods demonstrated high activity at high reaction temperature. But, the efficiency of the catalyst is diminished within several months when high temperature operation continues . To overcome the said problems of the conventional methods, the present invention provides a method for preparing chlorine from hydrogen chloride, in which cerium oxide having excellent stability and durability and far less expensive than the said platinum based catalyst is used as a catalyst for oxidation.
[Disclosure]
[Technical Problem]
It is an object of the present invention, to overcome the problems of the conventional methods, to provide a method for preparing chlorine using a novel catalyst which requires lower reaction temperature, has high activity and stability enough to maintain catalytic activity for a long reaction time, and has benefits for economy.
[Technical Solution]
The method of the present invention is characterized by using a cerium compound as a catalyst for the production of chlorine by oxidizing hydrogen chloride with oxygen containing gas .
The cerium compound herein is preferably cerium oxide, cerium complex oxide or a mixture thereof, and the cerium compound is preferably selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof .
The cerium compound is preferably an oxide of a compound selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof.
The cerium compound is more preferably cerium oxide. The catalyst above is preferably prepared by loading the cerium compound in a support or by oxidation of the cerium compound loaded in a support .
The content of the cerium compound in the support is preferably 1-10 weight%. The cerium compound is preferably in the shape of particle of 100 ran - 100 μm in size.
In this invention, the cerium compound is used as a main catalyst and one or more metals selected from platinum group elements or one or more metal compounds of metals selected from platinum group elements as a cocatalyst. The preferable content of the cocatalyst in the catalyst is 1-50 weight%.
The method of the present invention is characterized by preparing chlorine at 250-400°C in the presence of the cerium based catalyst (a catalyst using the said cerium compound) . [Advantageous Effect]
The cerium based catalyst used for the preparation of chlorine in this invention has lower reaction temperature of up to 400°C, has high activity, and has high stability, so that it maintains catalytic activity for a long time of reaction and thus has a merit for economy.
[Description of Drawings]
The above and other objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:
Figure 1 is a graph illustrating the result of X-ray fraction with the cerium oxide before and after the reaction of Example 8.
[Best Mode]
The key technique of the method of the present invention is to produce chlorine by oxidizing hydrogen chloride with oxygen containing gas in the presence of a cerium compound.
The method of the present invention is described in more detail hereinafter. Technical and scientific terms used herein indicate general meanings understood by those in the art, if stated otherwise. Hereinafter, well-known functions and compositions that might lure to wrong direction are rather not described.
The method of the present invention is to commercialize the process of chlorine production based on gas phase reaction of hydrogen chloride in a catalytic reactor. Particularly, the present invention relates to a catalyst that is capable of preventing the reduction of catalytic activity by exothermic reaction and thus is economical. The reaction between hydrogen chloride and oxygen in a catalytic reactor is represented by the following reaction formula 1.
4HCl + O2 <→ 2Cl2 +2H2O (1)
As shown in reaction formula 1, theoretical ratio of hydrogen chloride to oxygen(02) is 4:1 and the reaction is exothermic reaction. So, it is economically advantageous and more effective in preventing damage of a catalyst to generate chlorine at a temperature as low as possible as long as the catalyst maintains its catalytic activity.
The cerium compound herein is preferably cerium oxide, cerium complex oxide or a mixture thereof , and the cerium compound is preferably selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof .
The cerium compound is preferably an oxide of a compound selected from the group consisting of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide and a mixture thereof.
The cerium compound is more preferably cerium oxide.
The cerium compound of the present invention can be prepared by the conventional method. Or a commercial cerium compound can be used. The method for preparing cerium complex oxide is exemplified by coprecipitation method, dispersion method (dispersion and heat treatment) and impregnation method.
To be used as a catalyst, the cerium compound is prepared as particles having the size of 100 nm - 100 jM or as granules composed of the particles. This particle type or granule type cerium compound can be filled in a reactor or can be loaded in a support .
If the cerium compound of the present invention is cerium oxide or cerium complex oxide, the catalyst is loaded in a support. Or, if the cerium compound of the present invention is not cerium oxide, the cerium compound is loaded in a support first and then oxidized. Preferably, cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide or a mixture thereof is loaded in a support and oxidized in the presence of oxygen at 450-1300°C to produce a cerium oxide catalyst.
The support herein is any support used for the commercial reaction of chlorine preparation from hydrogen chloride by gas phase reaction, which is preferably exemplified by titanium oxide, alumina, silica, zirconium oxide, zeolite, titanium complex oxide, zirconium complex oxide, aluminum complex oxide and silicon complex oxide. The support herein preferably has micro-pores. To load a cerium compound into a support, impregnation method or equilibrium absorption method can be used.
The content of the cerium compound loaded in a support is preferably 1 - 10 weight% by the support. The above range of the content is preferable condition for a catalyst to maintain the catalytic activity with minimizing the reduction of specific surface area of the support.
The cerium compound is preferably in the shape of particle of 100 nm - 100 μm in size. This sized particle is advantageous for maintaining stability at high temperature, for preventing over-heating by exothermic reaction to produce chlorine and for obtaining high conversion rate (high chlorine yield) by maximizing surface area of the catalyst. The cerium compound of 100 nm - 100 μm in size can be loaded in a support or fills a reaction tube as a catalyst.
The size of the cerium compound particle can be regulated by pulverizing a commercial cerium compound and filtering thereof, or by optimizing heat -treatment temperature and heat- treatment time after synthesis, or by optimizing synthesis condition itself .
In this invention, the cerium compound is used as a main catalyst and one or more metals selected from platinum group elements or one or more metal compounds of metals selected from platinum group elements as a cocatalyst. The cocatalyst herein is added in order to increase the activity of the cerium compound and preferable content of such cocatalyst is 1-50 weight% by the total weight of the catalyst.
The method of the present invention is characterized by lower temperature reaction of at 250-400 °C, more preferably at 300-350°C, in the presence of the cerium based catalyst (cerium compound catalyst as mentioned above) to produce chlorine.
(Example 1)
A glass reactor having 1" of inside diameter was used. Hydrogen chloride gas and oxygen gas, the reactants, were added to the reactor at the ratio of 1:1. Flow rates of the reactants were 25 ml/min respectively. The reactor was filled with cerium oxide (Hanwha Chemical Co., Cat. #: CED30S) of 10 μm in mean diameter at the density of 0.4 g/cm3. The reactor was 20 cm long and the temperature of the reactor was maintained as 350°C . After 2 hours from the initiation of the reaction after supplying necessary gases (reactants) to the reactor, generated gas was captured and analyzed by Orsat method. Reactions were induced by the same manner as described in Example 1 except that different reactors and reaction temperatures were used (30 cm / 300°C: Example 2, 50 cm / 350°C: Example 3, 100 cm / 350°C: Example 4) .
Results of the reactions in Examples 1 - 4 are shown in Table 1.
Conversion rate was calculated by the comparison of the amount of chlorine gas generated from the reaction and the amount of non-reacted hydrogen chloride gas, according to the following formula: Conversion Rate (%) = (amount of chlorine gas generated*2) / (amount of hydrogen chloride before the reaction) *100
(Table 1)
Figure imgf000016_0001
(Example 5)
A glass reactor (inside diameter: 1", length: 100 cm) was filled with the cerium compound of Example 1 at the density of 0.4g/cm3. Hydrogen chloride gas and oxygen gas, the reactants, were provided to the reactor at the molar ratio of 1:2. Flow rate of the hydrogen chloride gas: oxygen gas was 25:50 ml/min. At that time, temperature of the reactor was maintained at 350°C.
Experiments were performed by the same manner as described in Example 5 except that the flow rate of hydrogen chloride gas: oxygen gas was adjusted to 17:34 ml/min and temperature of the reactor was maintained at 300°C (Example 6) and the flow rate of hydrogen chloride gas: oxygen gas was adjusted to 17:34 ml/min and temperature of the reactor was maintained at 350 °C (Example 7) . From 2 hours after the reaction was started, in Examples 5 - 7, generated gas was captured and analyzed by Orsat method and the results are shown in Table 2.
(Table 2)
Figure imgf000017_0001
(Example 8)
Reaction was induced by the same manner as described in Example 5 except that the temperature of the reactor was maintained at 400°C. The catalytic activity was examined by analyzing reaction gas (conversion rate for the first 2 hours: 53.5%, conversion rate for 100 hours: 52.7%) . Non-used catalyst and used catalyst after 100 hours of the reaction were investigated by X-ray fraction and the results are shown in Figure 1. As shown in Figure 1 , there was no change in the structure of the catalyst used for 100 hours of the reaction at the high temperature of 400°C.
In Examples 1 - 8 , pure cerium compound alone was used as a catalyst. As a result, the method for preparing chlorine using the cerium based catalyst of the present invention was confirmed to have economical advantages because it gives high conversion rate of at least 60% at up to 400°C; maintains catalytic activity at even high temperature of 400°C, maintains stable structure, activity and stability at high-temperature without platinum group elements.
Those skilled in the art will appreciate that the conceptions and specific embodiments disclosed in the foregoing description may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present invention. Those skilled in the art will also appreciate that such equivalent embodiments do not depart from the spirit and scope of the invention as set forth in the appended claims.

Claims

[CLAIMS]
[Claim l]
A method for preparing chlorine by oxidizing hydrogen chloride with oxygen containing gas, in which a cerium compound is used as a catalyst.
[Claim 2]
The method for preparing chlorine according to claim 1, wherein the cerium compound is cerium oxide.
[Claim 3]
The method for preparing chlorine according to claim 1, wherein the cerium compound is cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide or a mixture thereof.
[Claim 4]
The method for preparing chlorine according to claim 2, wherein the cerium compound is an oxide of cerium acetate, cerium ammonium nitrate, cerium ammonium sulfate, cerium carbide, cerium carbonate, cerium chloride, cerium nitrate, cerium perchlorate, cerium sulfide or a mixture thereof.
[Claim 5]
The method for preparing chlorine according to claim 1, wherein the catalyst is prepared as loaded in a support.
[Claim 6]
The method for preparing chlorine according to claim 4, wherein the catalyst is loaded in a support and oxidized therein.
[Claim 7]
The method for preparing chlorine according to claim 5, wherein the content of cerium compound in a support is 1 - 10weight%.
[Claim 8]
The method for preparing chlorine according to claim 1, wherein the cerium compound is in the shape of particle of 100 nm - 100 μm in size.
[Claim 9]
The method for preparing chlorine according to claim 1, wherein the catalyst contains a cerium compound as a main catalyst and additionally includes one or more metals selected from platinum group elements or one or more metal compounds of metals selected from platinum group elements as a cocatalyst.
[Claim 10]
The method for preparing chlorine according to claim 9, wherein the content of the cocatalyst is 1 - 50 weight% by the total weight of the catalyst.
[Claim 11]
The method for preparing chlorine according to any of claim 1 - claim 10, wherein the chlorine is prepared at 250 - 400°C.
PCT/KR2008/005241 2007-09-10 2008-09-04 Process for the chlorine by oxidation of hydrogen chloride WO2009035234A2 (en)

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2010133313A1 (en) * 2009-05-16 2010-11-25 Bayer Materialscience Ag Process for preparing chlorine by gas phase oxidation of hydrogen chloride in the presence of a cerium oxide catalyst
WO2013004649A1 (en) 2011-07-05 2013-01-10 Bayer Intellectual Property Gmbh Process for the production of chlorine using a cerium oxide catalyst in an adiabatic reaction cascade
WO2013004651A1 (en) 2011-07-05 2013-01-10 Bayer Intellectual Property Gmbh Process for the production of chlorine using a cerium oxide catalyst in an isothermic reactor
WO2013060628A1 (en) 2011-10-24 2013-05-02 Bayer Intellectual Property Gmbh Catalyst and method for producing chlorine by means of a gas-phase oxidation
EP3421416A1 (en) 2017-06-29 2019-01-02 Covestro Deutschland AG Photocatalytic oxidation of hydrogen chloride with carbon monoxide
EP3670444A1 (en) 2018-12-18 2020-06-24 Covestro Deutschland AG Photocatalytic oxidation of hydrogen chloride with oxygen

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR950016873A (en) * 1993-12-01 1995-07-20 김은영 Cerium chloride-dichromium trioxide catalyst for the production of chlorine by oxidation of hydrogen chloride and preparation method thereof
KR970015456A (en) * 1995-09-12 1997-04-28 랑핑거, 스타인호프 Preparation of chlorine from hydrogen chloride
KR20020056939A (en) * 1999-11-22 2002-07-10 그래햄 이. 테일러 Process for vinyl chloride manufacture from ethane and ethylene with immediate HCl recovery from reactor effluent

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR950016873A (en) * 1993-12-01 1995-07-20 김은영 Cerium chloride-dichromium trioxide catalyst for the production of chlorine by oxidation of hydrogen chloride and preparation method thereof
KR970015456A (en) * 1995-09-12 1997-04-28 랑핑거, 스타인호프 Preparation of chlorine from hydrogen chloride
KR20020056939A (en) * 1999-11-22 2002-07-10 그래햄 이. 테일러 Process for vinyl chloride manufacture from ethane and ethylene with immediate HCl recovery from reactor effluent

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
GRUY F. ET AL. J. AM. CERAM. SOC. vol. 77, 1994, pages 1537 - 1544 *

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WO2010133313A1 (en) * 2009-05-16 2010-11-25 Bayer Materialscience Ag Process for preparing chlorine by gas phase oxidation of hydrogen chloride in the presence of a cerium oxide catalyst
JP2014520742A (en) * 2011-07-05 2014-08-25 バイエル インテレクチュアル プロパティー ゲゼルシャフト ミット ベシュレンクテル ハフツング Method for producing chlorine using cerium oxide catalyst in adiabatic reaction cascade
WO2013004649A1 (en) 2011-07-05 2013-01-10 Bayer Intellectual Property Gmbh Process for the production of chlorine using a cerium oxide catalyst in an adiabatic reaction cascade
WO2013004651A1 (en) 2011-07-05 2013-01-10 Bayer Intellectual Property Gmbh Process for the production of chlorine using a cerium oxide catalyst in an isothermic reactor
CN103764548A (en) * 2011-07-05 2014-04-30 拜耳知识产权有限责任公司 Process for the production of chlorine using a cerium oxide catalyst in an isothermic reactor
WO2013060628A1 (en) 2011-10-24 2013-05-02 Bayer Intellectual Property Gmbh Catalyst and method for producing chlorine by means of a gas-phase oxidation
CN103889568A (en) * 2011-10-24 2014-06-25 拜耳知识产权有限责任公司 Catalyst and method for producing chlorine by means of a gas-phase oxidation
JP2014534062A (en) * 2011-10-24 2014-12-18 バイエル・インテレクチュアル・プロパティ・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツングＢａｙｅｒ Ｉｎｔｅｌｌｅｃｔｕａｌ Ｐｒｏｐｅｒｔｙ ＧｍｂＨ Catalyst and method for producing chlorine by gas phase oxidation
CN103889568B (en) * 2011-10-24 2017-04-19 科思创德国股份有限公司 Catalyst and method for producing chlorine by means of a gas-phase oxidation
JP2018089625A (en) * 2011-10-24 2018-06-14 バイエル・インテレクチュアル・プロパティ・ゲゼルシャフト・ミット・ベシュレンクテル・ハフツングＢａｙｅｒ Ｉｎｔｅｌｌｅｃｔｕａｌ Ｐｒｏｐｅｒｔｙ ＧｍｂＨ Catalyst and method for producing chlorine by vapor phase oxidation
EP3421416A1 (en) 2017-06-29 2019-01-02 Covestro Deutschland AG Photocatalytic oxidation of hydrogen chloride with carbon monoxide
EP3670444A1 (en) 2018-12-18 2020-06-24 Covestro Deutschland AG Photocatalytic oxidation of hydrogen chloride with oxygen
WO2020127022A1 (en) 2018-12-18 2020-06-25 Covestro Intellectual Property Gmbh & Co. Kg Photocatalytic oxidation of hydrochloric acid using oxygen

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