CN104549360A - Catalyst for producing chlorine by catalytic oxidation of hydrogen chloride - Google Patents

Abstract

The present invention relates to a catalyst used in the process of catalyzing the oxidation of hydrogen chloride to produce chlorine, in particular to a catalyst containing ruthenium, copper, alkali metal elements and rare earth metal elements prepared by a double impregnation method, the catalyst has a core-shell structure.

Description

A kind of catalyst for catalytic oxidation of hydrogen chloride to produce chlorine

technical field

The present invention relates to a catalyst used in the process of catalyzing the oxidation of hydrogen chloride to produce chlorine, in particular to a catalyst containing ruthenium, copper, alkali metal elements and rare earth metal elements prepared by a double impregnation method, the catalyst has a core-shell structure.

Background technique

In metallurgy, textile, medicine, chlor-alkali, petrochemical and other industries, the amount of hydrogen chloride produced in the form of by-products is huge. How to deal with a large amount of hydrogen chloride has become an urgent problem to be solved. At present, the main treatment measure actually adopted in the industry is to absorb hydrogen chloride with water and make it into low-quality and cheap hydrochloric acid for sale; due to the low price of hydrochloric acid and the limited market demand capacity, making hydrogen chloride into hydrochloric acid has actually become a burden rather than a waste For treasure. There are also some treatment measures that are used to neutralize hydrogen chloride with alkali and then discharge directly; however, with the improvement of environmental protection laws and regulations, the environmental protection standards of various discharge methods are already very strict.

Therefore, the industrialized method of producing chlorine from hydrogen chloride has received continuous attention from related industries. Because the method of directly making chlorine gas from the by-product hydrogen chloride can not only realize the closed cycle of chlorine element, but also realize zero discharge in the reaction process. So far, the methods for preparing chlorine from hydrogen chloride can be mainly divided into three categories: electrolysis, direct oxidation and catalytic oxidation. However, the energy consumption of the electrolysis process is too large, and the ionic membrane needs to be replaced frequently, so the cost is very high, and the recovery cost per ton of chlorine gas is more than 4,000 yuan; the yield of the direct oxidation method is low and cannot be industrialized; it is comparable to the electrolysis method and the direct oxidation method. Compared with other methods, the catalytic oxidation method, especially the catalytic oxidation method via the Deacon reaction, has the most industrial potential.

The Deacon reaction is the oxidation of hydrogen chloride to chlorine gas in the presence of a catalyst. The Deacon reaction equation is: The performance of the catalyst has a great influence on the effect of the Deacon reaction. Therefore, in order to realize the industrialization of the Decon reaction, researchers at home and abroad have done a lot of research to find suitable catalysts.

The catalysts used in the Deacon reaction are classified by active components, mainly metal elements such as chromium, ruthenium, and copper. Among them, chromium-based catalysts are more polluting to the environment; ruthenium-based catalysts are expensive; copper-based catalysts have only low activity at low temperatures, but are prone to loss at high temperatures, resulting in reduced catalytic activity.

EP0184413 discloses a method for catalyzing the oxidation of hydrogen chloride with chromium oxide as a catalyst, but the catalyst activity is low; because chromium and chlorine can easily form chromium oxychloride with a low boiling point, and a higher reaction temperature will easily deactivate the catalyst. US5707919 discloses an improved method of chromium oxide catalyst, the catalyst prepared by the method has high catalytic activity, relatively long service life, and the conversion rate of hydrogen chloride is 85.2%. In addition, CN1126637A, CN85109387A, CN87105455A, etc. disclose catalysts with chromium oxide as the main component, but due to the relatively high toxicity of chromium, chromium oxide catalysts have serious environmental pollution problems, which limit their industrial application.

GB2120225 adopts co-precipitation method to prepare a copper oxide catalyst supported by titanium dioxide, but a large amount of wastewater containing heavy metal ions is produced during the catalyst preparation process. US4123389 discloses a copper oxide catalyst supported by silica gel, titanium oxide or aluminum oxide; however, since the catalyst impregnation process needs to be carried out in an organic solvent, the pollution to the environment is relatively serious. CN101125297A discloses taking copper chloride, potassium chloride and cerium chloride as catalyzer on the aluminum oxide carrier, and then the catalyst is processed with phosphoric acid; due to the _CuCl2 active components are easily lost at higher reaction temperatures, resulting in catalyst shorter service life. CN102658149A discloses a copper-based catalyst composed of CuO, K ₂ O and a carrier, but the catalyst has a low conversion rate of hydrogen chloride, the highest being only 88.6%. CN102000583A discloses a catalyst that takes copper as the main active component and adds additives such as boron, transition metal elements, rare earth elements, and alkali metals/alkaline earth metals; but after the catalyst reacts for 100 hours, the highest chlorine yield is 89%, and further research is needed. improve.

GB1046313 discloses a supported RuCl ₃ catalyst based on silica gel, pumice and Al ₂ O ₃ , but the catalyst is easily deactivated. US5908607A discloses a catalyst with _RuO2 as the main component, but the catalytic activity of the catalyst will gradually decrease with the prolongation of the operating time, and it is also easy to cause irreversible damage due to impurities in the hydrogen chloride raw material and errors in the process operation. inactivated by poisoning. TW200812909A describes a catalyst comprising tin dioxide and at least one ruthenium-containing compound.

Summary of the invention

In order to overcome the shortcomings of the prior art, the invention provides a composite catalyst for catalyzing the oxidation of hydrogen chloride to produce chlorine.

In one aspect, the present invention relates to a catalyst for catalyzing the oxidation of hydrogen chloride to produce chlorine, which contains ruthenium, copper, alkali metal elements and rare earth metal elements.

In another aspect, the present invention also relates to a method for preparing a catalyst for catalytic oxidation of hydrogen chloride to produce chlorine, comprising:

a) Dissolving the copper-containing compound, the alkali metal-containing compound and the rare earth metal-containing compound in the first liquid to prepare a first solution, adding a carrier to the first solution and impregnating it for the first time;

b) filtering off the first solution to obtain a primary impregnated carrier, drying and primary calcining the primary impregnated carrier to obtain a primary calcined carrier;

c) Dissolving the ruthenium-containing compound in the second liquid to make a second solution, adding the initially calcined carrier and impregnating it a second time;

d) filtering off the second solution to obtain a second impregnated carrier, drying and calcining the second impregnated carrier again to obtain a catalyst.

In another aspect, the present invention also relates to a method for catalytically oxidizing hydrogen chloride to produce chlorine, comprising:

a) supplying a hydrogen chloride-containing feed gas stream and an oxygen-containing stream for oxidizing said hydrogen chloride;

b) contacting the hydrogen chloride-containing feed gas stream and the oxygen-containing stream for oxidizing the hydrogen chloride with the catalyst of the present invention for reaction;

c) separating and obtaining chlorine gas from the reacted stream.

In another aspect, the present invention also relates to the use of the catalyst for catalytic oxidation of hydrogen chloride to produce chlorine, comprising: contacting the hydrogen chloride-containing feed gas stream and the oxygen-containing stream for oxidizing the hydrogen chloride with the catalyst of the present invention for reaction.

The catalyst of the invention has the beneficial effects of maintaining high activity at low reaction temperature and high stability with time.

Detailed description of the invention

The contriver finds through research, and the main shortcoming of catalyst in the prior art Deacon method is that activity is lower at low reaction temperature, and raising reaction temperature causes catalyst loss and then reduces reaction efficiency; In addition, the stability of catalyst over time Sex also needs to be improved. The catalyst of the invention significantly improves the activity of the catalyst, can maximize the utilization of the catalytic ability of each component, eliminates the loss of the catalyst caused by local overheating of the catalyst, and improves the thermal stability of the catalyst during use.

In one aspect, the present invention relates to a catalyst for catalyzing the oxidation of hydrogen chloride to produce chlorine, which contains ruthenium, copper, alkali metal and rare earth metal components, and is characterized in that: the content of copper accounts for 3.0-26.0 wt% of the weight of the catalyst; The content of the metal accounts for 0.2-4.0 wt% of the weight of the catalyst; the content of the rare earth metal accounts for 0.2-2.0 wt% of the weight of the catalyst; the content of ruthenium accounts for 2.0-8.0 wt% of the weight of the catalyst.

The content of copper in the present invention can be any value in the range of 3.0-26.0wt% or a range formed by any combination of values in the range, such as 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5% , 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.2%, 9.4%, 9.6%, 9.8%, 10.0%, 10.2%, 10.4%, 10.6%, 10.8%, 11.0 %, 11.2%, 11.4%, 11.6%, 11.8%, 12.0%, 12.2%, 12.4%, 12.6%, 12.8%, 13.0%, 13.2%, 13.4%, 13.6%, 13.8%, 14.0%, 14.2%, 14.4%, 14.6%, 14.8%, 15.0%, 15.2%, 15.4%, 15.6%, 15.8%, 16.0%, 16.5%, 17.0%, 17.5%, 18.0%, 18.5%, 19.0%, 19.5%, 20.0% , 20.5%, 21.0%, 21.5%, 22.0%, 22.5%, 23.0%, 23.5%, 24.0%, 24.5%, 25.0%, 25.5%, 26.0%wt, etc., or the range formed by any combination of listed values . In various embodiments of the present invention, the content of copper preferably accounts for 9.0-16.0 wt% of the weight of the catalyst, more preferably accounts for 9.2-11.4 wt% of the weight of the catalyst.

The content of the alkali metal in the present invention can be any value in the range of 0.2 to 4.0 wt% or a range formed by any combination of values in the range, such as 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% %, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0% wt, etc., or the range formed by any combination of listed values. In various embodiments of the present invention, the content of the alkali metal is preferably 0.5-2.6 wt%, more preferably 0.6-1.1 wt%, of the catalyst.

The content of the rare earth metal in the present invention can be any value in the range of 0.2 to 2.0 wt% or a range formed by a combination of any value in the range, such as 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7% %, 0.8%, 0.9%, 1.0%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%wt, etc., or any value listed range formed by the combination. In various embodiments of the present invention, the content of the rare earth metal is preferably 0.4-1.2 wt%, more preferably 0.6-1.2 wt%, of the catalyst.

The content of ruthenium in the present invention can be any value in the range of 2.0-8.0wt% or the range formed by any combination of values in the range, such as 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5% , 2.6%, 2.7%, 2.8%, 2.9%, 3.0%, 3.1%, 3.2%, 3.3%, 3.4%, 3.5%, 3.6%, 3.7%, 3.8%, 3.9%, 4.0%, 4.1%, 4.2 %, 4.3%, 4.4%, 4.5%, 4.6%, 4.7%, 4.8%, 4.9%, 5.0%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, 5.6%, 5.7%, 5.8%, 5.9%, 6.0%, 6.1%, 6.2%, 6.3%, 6.4%, 6.5%, 6.6%, 6.7%, 6.8%, 6.9%, 7.0%, 7.1%, 7.2%, 7.3%, 7.4%, 7.5% , 7.6%, 7.7%, 7.8%, 7.9%, 8.0%wt, etc., or the range formed by any combination of listed values. In various embodiments of the present invention, the content of ruthenium preferably accounts for 2.5-5.0 wt% of the weight of the catalyst, more preferably accounts for 3.0-5.0 wt% of the weight of the catalyst.

The alkali metal in the present invention is selected from lithium, sodium, potassium, rubidium, cesium and francium.

The rare earth metal of the present invention is selected from scandium (Sc), yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium ( Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu).

In another aspect, the present invention also relates to a method for preparing a catalyst for catalytic oxidation of hydrogen chloride to produce chlorine, comprising:

a) Dissolving the copper-containing compound, the alkali metal-containing compound and the rare earth metal-containing compound in the first liquid to prepare a first solution, adding a carrier to the first solution and impregnating it for the first time;

b) filtering off the first solution to obtain a primary impregnated carrier, drying and primary calcining the primary impregnated carrier to obtain a primary calcined carrier;

c) Dissolving the ruthenium-containing compound in the second liquid to make a second solution, adding the initially calcined carrier and impregnating it a second time;

d) filtering off the second solution to obtain a second impregnated carrier, drying and calcining the second impregnated carrier again to obtain a catalyst.

In various embodiments of the present invention, the copper-containing compound is selected from copper oxide and/or chloride, and the copper oxide is selected from copper oxide, cuprous oxide or a mixture of one or more thereof, copper Chloride is selected from copper chloride, cuprous chloride or a mixture of one or more thereof. In various embodiments of the invention, the copper-containing compound may be a hydrated salt.

The ruthenium-containing compound is selected from ruthenium chloride, ruthenium oxide, ruthenium oxychloride, ruthenium nitrate or a mixture of one or more thereof, preferably ruthenium chloride. In various embodiments of the invention, the ruthenium-containing compound may be a hydrated salt.

The alkali metal-containing compound is selected from potassium chloride, sodium chloride, potassium nitrate, sodium nitrate or a mixture of one or more thereof, preferably potassium chloride. In various embodiments of the invention, the alkali metal-containing compound may be a hydrated salt.

The rare earth metal-containing compound is selected from chloride or nitrate of lanthanum or cerium, or a mixture of one or more thereof, preferably cerium chloride. In various embodiments of the present invention, the rare earth metal-containing compound may be a hydrated salt.

The carrier is selected from aluminum oxide, titanium dioxide, tin oxide, silicon oxide, zirconium oxide or a mixture of one or more thereof, preferably aluminum oxide, most preferably γ- aluminum oxide.

The primary impregnation and the secondary impregnation may be the same or different. The time for the primary impregnation or the secondary impregnation is 6-15 hours, preferably 8-12 hours. The primary impregnation or the secondary impregnation is preferably ultrasonic-assisted impregnation, wherein during the initial impregnation, the ultrasonic-assisted impregnation time is 5 to 30 minutes, preferably 10 to 20 minutes; or during the second impregnation, the ultrasonic-assisted impregnation time is 20 minutes to 60 minutes, preferably 30 to 50 minutes. Those skilled in the art know that the suitable time for primary impregnation and secondary impregnation in the present invention can be determined by means known to those skilled in the art.

The first liquid or the second liquid may be selected from distilled water, dilute nitric acid, dilute hydrochloric acid and the like.

The temperature of the primary calcination is 300-700°C, preferably 350-450°C, and the time is 3-6 hours; preferably 4-5 hours. The primary calcination is preferably performed under an air atmosphere. Those skilled in the art know that the suitable initial calcination time and temperature in the present invention can be determined by means known to those skilled in the art.

The recalcination temperature is 200-600°C, preferably 300-500°C, and the time is 2-5 hours; preferably 2-3 hours. The recalcination is preferably performed under an air atmosphere. Those skilled in the art know that the suitable recalcination time and temperature in the present invention can be determined by means known to those skilled in the art.

The conditions for the first drying are as follows: the temperature is 100-130° C., preferably 120° C., the time is 0.5-16 hours, and the drying ends at 120° C. for 1 hour with a weight loss of ≤1%.

The re-drying conditions are as follows: the temperature is 100-130° C., preferably 120° C., the time is 0.5-16 hours, and the weight loss is ≤1% after drying at 120° C. for 1 hour.

In another aspect, the present invention also relates to a method for catalytically oxidizing hydrogen chloride to produce chlorine, comprising:

a) supplying a hydrogen chloride-containing feed gas stream and an oxygen-containing stream for oxidizing said hydrogen chloride;

b) contacting the hydrogen chloride-containing feed gas stream and the oxygen-containing stream for oxidizing the hydrogen chloride with the catalyst of the present invention for reaction;

c) separating and obtaining chlorine gas from the reacted stream.

The hydrogen chloride-containing feed gas described in the present invention includes hydrogen chloride in the form of by-products from related industrial productions such as production of isocyanates, production of acid chlorides, chlorination of aromatic compounds, and the like. The hydrogen chloride in the form of by-product may be the by-product hydrogen chloride that has undergone preliminary treatment or the by-product hydrogen chloride directly from related industries without any treatment.

The oxygen-containing stream according to the present invention may be a gas in the form of pure oxygen or other oxygen-containing gas (such as air).

The method of the present invention can be carried out in a continuous or batch reaction mode, preferably a continuous reaction mode.

In another aspect, the present invention also relates to the use of the catalyst for catalytic oxidation of hydrogen chloride to produce chlorine, comprising: contacting the hydrogen chloride-containing feed gas stream and the oxygen-containing stream for oxidizing the hydrogen chloride with the catalyst of the present invention for reaction.

The catalyst of the invention has the beneficial effects of maintaining high activity at low reaction temperature and high stability over time. Specifically, the catalyst of the present invention significantly improves the activity of the catalyst, can maximize the utilization of the catalytic ability of each component, eliminates the loss of the catalyst caused by local overheating of the catalyst, and improves the thermal stability of the catalyst during use. The preparation method of the catalyst of the present invention improves the stability of the catalyst by adopting two impregnation methods. The invention adopts ultrasonic assisted impregnation, and the ultrasonic can promote the dispersion of catalyst active components on the surface of the catalyst, and the distribution is more uniform, and can promote the increase of the content of catalyst surface active components. The catalyst prepared by the method can fully exert the oxidation performance of ruthenium at a lower temperature during the catalytic oxidation process, and the calcined ruthenium-containing compound forms ruthenium oxide to coat the surface of copper. As the reaction releases heat and the temperature rises, the high-temperature catalytic performance of copper can be exerted, and at the same time, the shell formed by ruthenium oxide can prevent the loss of copper. In a fixed bed or a fluidized bed with a temperature of 300°C to 420°C, by using the catalyst of the present invention, the conversion rate of hydrogen chloride can be over 90%, or a reaction mixture with a chlorine content of over 50% can be obtained.

In the following, the present application will be described in specific implementation manners. These specific embodiments are exemplary rather than restrictive. Through comparison between these examples and comparative examples, those skilled in the art can recognize that the present invention has unexpected technical effects.

Detailed ways

Example 1

Catalyst preparation: a) 2.5 grams of copper chloride dihydrate, 0.20 grams of potassium chloride and 0.25 grams of heptahydrate cerium trichloride are added to an appropriate amount of distilled water to make the first solution, and in the first solution Add the carrier and soak for 8 hours for the first time;

b) filtering off the first solution to obtain a primary impregnated carrier, drying the primary impregnated carrier at a temperature of 400° C. to obtain a primary calcined carrier;

c) dissolving 1.0 g of ruthenium trichloride dihydrate compound with distilled water to prepare a second solution, adding the initially calcined carrier and impregnating it for a second time for 8 hours;

d) filtering off the second solution to obtain a second impregnated carrier, drying again and calcining the second impregnated carrier at a temperature of 400° C. to obtain a catalyst.

According to elemental analysis, the copper in the catalyst accounts for 5.2% of the catalyst weight, the potassium accounts for 0.5% of the catalyst weight, the rare earth metal cerium accounts for 0.4% of the catalyst weight, and the ruthenium accounts for 2.5% of the catalyst weight.

Example 2

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 4.5 grams

Potassium chloride: 0.25 grams

Cerium trichloride heptahydrate: 0.30 g

Ruthenium trichloride dihydrate: 1.85 g

According to elemental analysis, the copper in the catalyst accounts for 9.2% of the catalyst weight, the potassium accounts for 0.6% of the catalyst weight, the rare earth metal cerium accounts for 0.5% of the catalyst weight, and the ruthenium accounts for 5.0% of the catalyst weight.

Example 3

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 8.0 grams

Potassium chloride: 0.60 g

Cerium trichloride heptahydrate: 0.80 g

Ruthenium trichloride dihydrate: 1.2 g

According to elemental analysis, the copper in the catalyst accounts for 17.0% of the catalyst weight, the potassium accounts for 1.5% of the catalyst weight, the rare earth metal cerium accounts for 1.4% of the catalyst weight, and the ruthenium accounts for 2.8% of the catalyst weight.

Example 4

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 10 grams

Potassium chloride: 0.70 g

Cerium trichloride heptahydrate: 0.65 g

Ruthenium trichloride dihydrate: 2.0 g

According to elemental analysis, copper accounts for 24.0% of the weight of the catalyst, potassium accounts for 3.0% of the weight of the catalyst, rare earth metal cerium accounts for 1.0% of the weight of the catalyst, and ruthenium accounts for 5.0% of the weight of the catalyst.

Example 5

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 6.0 grams

Potassium chloride: 0.40 g

Cerium trichloride heptahydrate: 0.40 g

Ruthenium trichloride dihydrate: 1.5 g

According to elemental analysis, the copper in the catalyst accounts for 12.0% of the catalyst weight, the potassium accounts for 1.1% of the catalyst weight, the rare earth metal cerium accounts for 0.6% of the catalyst weight, and the ruthenium accounts for 3.5% of the catalyst weight.

Example 6

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 6.0 grams

Potassium chloride: 0.3 grams

Cerium trichloride heptahydrate: 0.85 g

Ruthenium trichloride dihydrate: 1.8 g

According to the elemental analysis, copper accounts for 11.3% of the weight of the catalyst, potassium accounts for 0.8% of the weight of the catalyst, rare earth metal cerium accounts for 1.2% of the weight of the catalyst, and ruthenium accounts for 4.1% of the weight of the catalyst.

Example 7

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 7.5 grams

Potassium chloride: 1.0 g

Cerium trichloride heptahydrate: 0.8 g

Ruthenium trichloride dihydrate: 2.0 g

According to elemental analysis, the copper in the catalyst accounts for 15.2% of the catalyst weight, the potassium accounts for 2.6% of the catalyst weight, the rare earth metal cerium accounts for 1.2% of the catalyst weight, and the ruthenium accounts for 4.8% of the catalyst weight.

Example 8

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 5 grams

Potassium chloride: 0.3 grams

Cerium trichloride heptahydrate: 0.3 g

Ruthenium trichloride dihydrate:: 1.3 g

According to elemental analysis, the copper in the catalyst accounts for 9.2% of the catalyst weight, the potassium accounts for 0.6% of the catalyst weight, the rare earth metal cerium accounts for 0.5% of the catalyst weight, and the ruthenium accounts for 3.0% of the catalyst weight.

Comparative Example 1

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 2.5 grams

Potassium chloride: 0.15 grams

Cerium trichloride heptahydrate: 0.25 g

Ruthenium trichloride dihydrate: 6.0 g

Obtained through elemental analysis: the content of catalyst copper element accounts for 5.6% of catalyst weight, the content of potassium metal element accounts for 0.5% of catalyst weight, the content of rare earth metal cerium element accounts for 0.4% of catalyst weight, and the content of ruthenium element accounts for catalyst weight 15.2 percent.

Comparative Example 2

The preparation method of the catalyst is as in Example 1.

Copper chloride dihydrate: 14.0 g

Potassium chloride: 0.2 grams

Cerium trichloride heptahydrate: 0.35 g

Ruthenium trichloride dihydrate: 2.0 g

According to elemental analysis, the copper in the catalyst accounts for 30.3% of the catalyst weight, the potassium accounts for 0.6% of the catalyst weight, the rare earth metal cerium accounts for 0.6% of the catalyst weight, and the ruthenium accounts for 5.2% of the catalyst weight.

Comparative Example 3

Add 9.0 grams of copper chloride dihydrate and 1.0 grams of potassium chloride to an appropriate amount of distilled water to make a solution, add the carrier and impregnate for 8 hours; filter the solution after the impregnation is completed, dry the impregnated carrier first, and then The catalyst was obtained by calcining at 400°C. According to elemental analysis, the copper in the catalyst accounts for 17.2% of the weight of the catalyst, and the potassium accounts for 1.5% of the weight of the catalyst.

Comparative Example 4

The preparation method of the catalyst is as in Example 1.

Add 9.0 grams of copper chloride dihydrate, 1.0 grams of potassium chloride and 0.7 grams of cerium trichloride heptahydrate to an appropriate amount of distilled water to make a solution, add the carrier and impregnate for 8 hours; bake the impregnated carrier first Dry and then calcined at 400°C to obtain the catalyst. Obtained through elemental analysis: in the catalyst, copper accounts for 16.8% of the catalyst weight, potassium accounts for 1.5% of the catalyst weight, and rare earth metal cerium accounts for 1.5% of the catalyst weight

Comparative Example 5

9.0 grams of copper chloride dihydrate, 1.0 grams of potassium chloride, 0.7 grams of cerium trichloride heptahydrate and 1.3 grams of ruthenium chloride dihydrate were added to an appropriate amount of distilled water to make a solution, and the carrier was impregnated for 8 hours; the impregnated carrier is first dried and then calcined at a temperature of 400° C. to obtain a catalyst. According to elemental analysis, the copper in the catalyst accounts for 17.0% of the catalyst weight, the potassium accounts for 1.5% of the catalyst weight, the rare earth metal cerium accounts for 1.4% of the catalyst weight, and the ruthenium accounts for 2.8% of the catalyst weight.

Comparative Example 6

Add 1.3 grams of ruthenium trichloride dihydrate to an appropriate amount of distilled water to make a solution, add the carrier and impregnate for 8 hours; dry the impregnated carrier first, and then calcinate it at a temperature of 400°C to obtain the first calcined carrier; use distilled water Dissolve 9.0 grams of the compound of cupric chloride dihydrate, 1.0 grams of potassium chloride and 0.7 grams of the compound of cerium trichloride heptahydrate to make a solution, add the carrier calcined for the first time in this embodiment and soak for 8 hours, dry Afterwards, the catalyst was calcined again at a temperature of 400°C. According to the elemental analysis, the copper catalyst weight in the catalyst is 17.0%, the potassium accounts for 1.5% of the catalyst weight, the rare earth metal cerium accounts for 1.4% of the catalyst weight, and the ruthenium accounts for 2.8% of the catalyst weight.

The above catalysts were tested:

Catalytic oxidation of hydrogen chloride is carried out in a fixed-bed reactor. Catalyst is added to the reactor. When the bed temperature rises to 360°C, hydrogen chloride and oxygen are passed through at a flow rate of 40ml/min and 20ml/min respectively. After the reaction is maintained for 2 hours, Absorb with 100ml of 30% KI solution for 5 minutes, and titrate the generated C1 ₂ with the calibrated Na ₂ S ₂ O ₃ solution. Calculate the conversion rate of HCl and the content of chlorine in the reaction gas, the results are shown in table 1:

Table 1

The catalyst of Example 7 was selected for further measurement of the stability over time. Catalytic oxidation of hydrogen chloride is carried out in a fixed-bed reactor. Catalyst is added to the reactor. When the bed temperature rises to 360°C, hydrogen chloride and oxygen are passed through at a flow rate of 40ml/min and 20ml/min respectively. At 80h, 168h, 309h, 452h, and 600h, the conversion rate of HCl and the content of chlorine gas are determined by absorbing 100ml of KI _solution with a concentration of 30% for 5 minutes, and titrating the resulting _HCl with calibrated _Na2S2O3 solution. Cl ₂ . Calculate the conversion ratio of HCl and the content of chlorine in the reaction gas, the results are shown in table 2:

Table 2: Catalyst performance test to embodiment 7

Reaction time/h HCl conversion (%) Chlorine content (%) 2 96.5 62.3 80 94.9 60.3 168 97.1 62.8 309 95.6 61.0 452 95.7 61.2 600 96.7 62.5

The catalyst of Example 8 was selected for further measurement of the stability over time. Catalytic oxidation of hydrogen chloride is carried out in a fixed-bed reactor. Catalyst is added to the reactor. When the bed temperature rises to 360°C, hydrogen chloride and oxygen are passed through at a flow rate of 40ml/min and 20ml/min respectively. At 76h, 180h, 345h, 538h, and _820h , the conversion rate of HCl and the content of chlorine gas are determined by absorbing 100ml of KI solution with a concentration of 30% for 5 minutes, and titrating the generated _HCl with calibrated _Na2S2O3 solution. Cl ₂ . Calculate the conversion ratio of HCl and the content of chlorine in the reaction gas, the results are shown in table 3:

Table 3: Catalyst performance test to embodiment 8

Reaction time/h HCl conversion (%) Chlorine content (%) 2 98.0 64.1 76 96.4 62.0 180 97.5 63.5 345 95.2 60.6 538 95.8 61.3 820 96.9 62.7

Claims (33)

1., for a catalyzer for catalyzed oxidation hydrogen chloride production chlorine, wherein containing ruthenium, copper, basic metal and rare earth component, it is characterized in that: the content of copper accounts for 3.0 ~ 26.0wt% of catalyst weight; Alkali-metal content accounts for 0.2 ~ 4.0wt% of catalyst weight; The content of rare earth metal accounts for 0.2 ~ 2.0wt% of catalyst weight; The content of ruthenium accounts for 2.0 ~ 8.0wt% of catalyst weight.

2. catalyzer according to claim 1, wherein the content of copper preferably accounts for 9.0 ~ 16.0wt% of catalyst weight, more preferably accounts for 9.2 ~ 11.4wt% of catalyst weight.

3. the catalyzer according to claim 1-2, wherein alkali-metal content preferably accounts for 0.5 ~ 2.6wt% of catalyst weight, more preferably accounts for 0.6 ~ 1.1wt% of catalyst weight.

4. the catalyzer according to claim 1-3, wherein the content of rare earth metal preferably accounts for 0.4 ~ 1.2wt% of catalyst weight, more preferably accounts for 0.6 ~ 1.2wt% of catalyst weight.

5. the catalyzer according to claim 1-4, wherein the content of ruthenium preferably accounts for 2.5 ~ 5.0wt% of catalyst weight, more preferably accounts for 3.0 ~ 5.0wt% of catalyst weight.

6. the catalyzer according to claim 1-5, wherein basic metal is selected from lithium, sodium, potassium, rubidium, caesium, francium.

7. the catalyzer according to claim 1-6, wherein rare earth metal is selected from scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium.

8. the catalyzer according to claim 1-7, wherein also comprise carrier, described carrier is selected from aluminium sesquioxide, titanium dioxide, stannic oxide, silicon oxide, zirconium white or its one or more mixture, preferred aluminium sesquioxide, most preferably γ-aluminium sesquioxide.

9. prepare a method for the catalyzer described in any one of claim 1-8, comprise:

A) by copper-containing compound, alkali metal-containing compound be dissolved in first liquid make the first solution containing rare earth compound, in described first solution, carrier is added and first impregnation;

B) the first solution described in elimination obtains the carrier that first impregnation is crossed, and first dries and the carrier crossed of the described first impregnation of first calcining thus obtain first burnt carrier;

C) be dissolved in second liquid containing ruthenium compound and make the second solution, add described first burnt carrier and double-steeping;

D) the second solution described in elimination obtains the carrier that double-steeping is crossed, and again dries and again calcines carrier that described double-steeping crosses thus obtain catalyzer.

10. method according to claim 9, wherein said copper-containing compound is selected from copper oxide and/or muriate.

11. methods according to claim 10, wherein said copper oxide is selected from cupric oxide, Red copper oxide or its one or more mixture.

12. methods according to claim 10, wherein said copper chloride is selected from cupric chloride, cuprous chloride or its one or more mixture.

13. methods according to claim 9-12, wherein said copper-containing compound can be the salt of hydration.

14. methods according to claim 9-13, are wherein saidly selected from ruthenium chloride, ruthenium oxide, oxychlorination ruthenium, nitric acid ruthenium or its one or more mixture containing ruthenium compound, preferred ruthenium chloride.

15. methods according to claim 9-14, wherein said can be the salt of hydration containing ruthenium compound.

16. methods according to claim 9-15, wherein said alkali metal-containing compound is selected from Repone K, sodium-chlor, saltpetre, SODIUMNITRATE or its one or more mixture, preferred Repone K.

17. methods according to claim 9-16, wherein said alkali metal-containing compound can be the salt of hydration.

18. methods according to claim 9-17, wherein said muriate or the nitrate being selected from lanthanum or cerium containing rare earth compound, or its one or more mixture, preferred Cerium II Chloride.

19. methods according to claim 9-18, wherein said can be the salt of hydration containing rare earth compound.

20. methods according to claim 9-19, wherein said carrier is selected from aluminium sesquioxide, titanium dioxide, stannic oxide, silicon oxide, zirconium white or its one or more mixture, preferred aluminium sesquioxide, most preferably γ-aluminium sesquioxide.

21. methods according to claim 9-20,6 ~ 15 hours time of wherein said first impregnation or described double-steeping, preferably 8 ~ 12 hours.

22. methods according to claim 9-21, wherein said first impregnation preferably adopts ultrasonic assistant to flood, and wherein during first impregnation, ultrasonic assistant dipping time is 5 ~ 30 minutes, is preferably 10 ~ 20 minutes.

23. methods according to claim 9-22, wherein said double-steeping preferably adopts ultrasonic assistant to flood, and wherein during double-steeping, ultrasonic assistant dipping time is 20 ~ 60 minutes, is preferably 30 ~ 50 minutes.

24. methods according to claim 9-23, wherein said first liquid or second liquid can be selected from distilled water, dust technology, dilute hydrochloric acid etc.

25. methods according to claim 9-24, the temperature of wherein said first calcining is 400 ~ 800 DEG C, preferably 500 ~ 600 DEG C, and the time is 2 ~ 5 hours; Preferably 2 ~ 3 hours; Described first calcining is preferably carried out in air atmosphere.

26. methods according to claim 9-25, wherein said temperature of again calcining is 200 ~ 600 DEG C, preferably 300 ~ 500 DEG C, and the time is 2 ~ 5 hours; Preferably 2 ~ 3 hours; Described calcining again is preferably carried out in air atmosphere.

27. methods according to claim 9-26, the condition of wherein said first oven dry is: temperature is 100 ~ 130 DEG C, preferably 120 DEG C, and the time is 0.5 ~ 16h.

28. methods according to claim 9-27, wherein said condition of again drying is: temperature is 100 ~ 130 DEG C, preferably 120 DEG C, and the time is 0.5 ~ 16h.

The method of 29. 1 kinds of catalyzed oxidation hydrogen chloride production chlorine, comprising:

A) containing hydrogen chloride feed gas stream and the oxygenous logistics for being oxidized described hydrogenchloride is supplied;

B) described containing hydrogen chloride feed gas stream and being used for is oxidized catalyst exposure described in the oxygenous logistics of described hydrogenchloride and any one of claim 1-8 to react;

C) from reacted logistics, separation obtains chlorine.

30. methods according to claim 29, wherein said containing hydrogen chloride unstripped gas comprises the hydrogenchloride of by-product form producing the production of such as isocyanic ester, the production, aromatic substance chlorination etc. of acyl chlorides from relevant industries.

31. according to the method for claim 29-30, and the oxygenous logistics described in it can be gas or other oxygen-containing gass (such as air) of pure form.

32. according to the method for claim 29-31, and wherein said method can adopt continuously or rhythmic reaction mode is carried out, and preferably adopts successive reaction mode.

Catalyzer described in 33. any one of claim 1-8 is used for the purposes of catalyzed oxidation hydrogen chloride production chlorine, comprising: by containing hydrogen chloride feed gas stream and be used for being oxidized catalyst exposure described in the oxygenous logistics of described hydrogenchloride and any one of claim 1-8 and react.