Ultralow mercury catalyst and production technology thereof
Technical field
The present invention relates to a kind of acetylene gas and hydrogen chloride gas and carry out mercury catalyst and the production technology thereof that addition reaction synthesizing chloroethylene is used, particularly a kind of ultralow mercury catalyst and production technology thereof.
Background technology
Polyvinyl chloride (PVC) is a kind of superior performance, broad-spectrum synthetic resin, the aggregated capacity of China PVC in 2012 is 2,300 ten thousand tons, yet oil-poor, weak breath abundant national conditions relative to coal resource, determined that China PVC produces raw material---vinyl chloride still be take carbide acetylene method production so far as main, calcium carbide process PVC accounts for the more than 80% of China PVC aggregated capacity at present.Calcium carbide process PVC investment of production is few, technique is relatively ripe, thereby we believe within the quite a long time from now on it will is the main flow technique of China's PVC Industry development, but calcium carbide process PVC production technology also exists many deficiencies, the most fatal be exactly as PVC raw materials for production---vinyl chloride is produced necessary mercury catalyst (mercury catalyst), the one, produce mercury catalyst and need consume a large amount of mercury chloride, and as the mercury of mercury chloride raw materials for production, Domestic Resources is day by day deficient; The 2nd, in use, mercury chloride pollution on the environment is very serious.
Above-mentioned vinyl chloride is produced necessary mercury catalyst and be take active carbon as carrier, with mercuric chloride solution, soak and make, be commonly called as " mercury catalyst ", its mercury chloride content is up to 10~15%, and in actual production, one ton of polyvinyl chloride of every production is wanted the so high mercury catalyst 1.2~1.5kg of mean consumption, and China calcium carbide process PVC in 2012 is produced and consumed 1200~1500 tons, mercury chloride, this wherein 50% mercury chloride cannot reclaim.China was once third place in the world great Chan Gong state, but mercury resource is exhausted now, without mercury, can adopt, and maintained reluctantly supply every year by import and recovery.Mercury or a global pollutant, can propagate by media such as atmosphere, water, mobility is very strong, after sedimentation, be further converted to methyl mercury, the harm that human health and environment are caused is very serious, thereby international community all pays close attention: the annual mercury emission of the U.S. is in legislation will be controlled at the scope of 10~15 tons; European Union forbade mercury outlet from 2011; Hold United Nations Environment Programme conference at ministerial level in Nairobi, Kenya capital in February, 2009, and the nearly all country in the whole world has all participated in current meeting, and sign the global treaty of an alleviation mercury pollution; " about strengthening the instruction of PVC Industry mercury pollution control " that the year ends 2009, Sinopec association, Chinese chlorine industry association, China Chemical Industry Epa drafted jointly formulates target " China's PVC Industry was all used low mercury catalyst in 2015; the useless mercury catalyst rate of recovery reaches 100% ", as do not realized as scheduled above-mentioned target, calcium carbide process PVC production industry in the pressure Xia,You of international convention and Domestic Environment policy China characteristic cannot continue survival.The final outlet of calcium carbide process PVC production industry is in the appearance without mercury catalyst, but even to this day, research and development without mercury catalyst not yet make great progress, the use amount of mercury can only be lowered at present, in the desired scope of the policy that is controlled at, and the mercury in the useless mercury catalyst of recovery as much as possible, when reducing mercury pollution, guarantee the raw material supply of mercury, change space with the time, like this, the life of calcium carbide process PVC production industry just can continue, yet up to the present, have not yet to see the progress report of industrial value.
We are according to the experience of long-term production mercuric chloride catalyst, and through concentrating on studies, learn on this basis: the active carbon of superelevation voidage carries out addition reaction synthesizing chloroethylene itself to acetylene gas and hydrogen chloride gas just higher activity and selectivity, will give play to huge synergy with a small amount of mercury chloride together with zinc chloride again, play the effect that high mercury chloride content catalyst can play, and add again a small amount of other compound barium chloride and potassium chloride, can also greatly improve its mechanical performance, extend its service life.By a large amount of experiments with update, we develop only 0.5~4.0% ultralow mercury catalyst of mercury chloride content, through on probation on commercial plant, have received good result.
Summary of the invention
Technical problem to be solved by this invention is to overcome above-mentioned the deficiencies in the prior art, and provides a kind of acetylene gas and hydrogen chloride gas to carry out ultralow mercury catalyst and production technology thereof that addition reaction synthesizing chloroethylene is used.
The present invention solves the technical scheme that its technical problem takes: a kind of acetylene gas and hydrogen chloride gas carry out the ultralow mercury catalyst that addition reaction synthesizing chloroethylene is used, and it is with carbon tetrachloride absorption>=70%, iodine number>=1000mg/g, moisture content≤5%, ash≤7%, mechanical strength>=95%, bulk density 360~420g/l, granularity 2.5~4.0mm, specific area 1000~1800m
2the wood activated charcoal of/g is carrier, and center absorption mercury chloride, collaborative promoter zinc chloride, barium chloride, potassium chloride, bismuth chloride are made, and by weight percentage, its chloride containing mercury 0.5~4.0%, is preferably 2.5~3.7%; Containing Zinc Chloride 2~10%, barium chloride 2~10%, potassium chloride 2~10%, bismuth chloride 2~10%, concrete production technology is:
1, the hydrochloric acid solution that is 0.1~5% with high purity hydrochloric acid and desalted water preparation mass fraction, standby;
2, selected wood activated charcoal is put in the hydrochloric acid solution of step 1 preparation and is soaked, preferably soak 20~60 minutes, during hydrochloric acid solution is constantly flowed, then take out be filtered dry, be dried to moisture below 3%;
3, with mercury chloride, hydrochloric acid and desalted water preparation mass fraction be 2~5%, the mercury chloride hydrochloric acid solution of pH≤3, and by the weight ratio of contained other material of the ultralow mercury catalyst mercury chloride contained with it of preparation, add appropriate collaborative promoter zinc chloride, barium chloride, potassium chloride, bismuth chloride, standby;
4, to finally be dried to moisture active carbon below 3% through step 2 immersion puts in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 4~10 hours, make during this time mercury chloride hydrochloric acid solution constantly flow, then take out and be filtered dry, put into baking oven, under the temperature conditions of 100~140 ℃, be dried to moisture below 0.3%, complete selected wood activated charcoal and adsorb for the first time mercury chloride work, then the active carbon that has adsorbed a mercury chloride is put into again in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 2~5 hours, and repeat to adsorb for the first time other operation in mercury chloride process, can complete selected wood activated charcoal and adsorb for the second time mercury chloride work, then again the active carbon that has adsorbed secondary mercury chloride is put into for the third time in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 2~5 hours, and repeat to adsorb for the second time other operation in mercury chloride process, complete the work of three absorption mercury chloride of selected wood activated charcoal, make selected wood activated charcoal center absorption mercury chloride, the ultralow mercury catalyst making by weight percentage, chloride containing mercury 0.5~4.0%, zinc chloride 2~10%, barium chloride 2~10%, potassium chloride 2~10%, bismuth chloride 2~10%.
This acetylene gas provided by the present invention and hydrogen chloride gas carry out the mercury catalyst that addition reaction synthesizing chloroethylene is used, mercury chloride content is ultralow, though only 0.5~4.0%, but because it occupies in activated carbon adsorptive capacity and the stronger center of reactivity, and be the wood activated charcoal of superelevation voidage owing to having added the active carbon of active component bismuth chloride and employing, also add collaborative promoter to make active carbon and mercury chloride give play to huge synergy simultaneously, catalytic activity is very high, thereby this catalyst has longer service life and higher activity, the high mercury catalyst that is 10.5~12.5% with mercury chloride content carries out the vinyl chloride synthetic test contrast under equal operating condition: the two does not have difference in serviceability, but mercury catalyst mercury chloride consumption provided by the present invention is very low, because catalyst mercury chloride content is low and long service life causes that catalyst amount reduces and then it is very obvious to reduce the effect of mercury chloride consumption and vinyl chloride production cost.
The specific embodiment
In order to illustrate better, the present invention enumerate following instance, but scope of the present invention is not limited only to this, its claimed scope is recorded in the claim of claim.
The embodiment of the present invention provides a kind of acetylene gas and hydrogen chloride gas to carry out the ultralow mercury catalyst that addition reaction synthesizing chloroethylene is used, and it is with 100 kilograms of carbon tetrachloride absorption 110% (GB/T12496-1999), iodine number 1200mg/g (GB/T12496-1999), moisture content 2% (GB/T12496-1999), ash 3% (GB/T12496-1999), mechanical strength 97% (ASTM racket method), bulk density 365g/l (GB/T12496-1999), granularity 2.5~3.8mm (GB/T12496-1999), specific area 1450m
2/ g(BET method) wood activated charcoal is carrier, center absorption mercury chloride, collaborative promoter zinc chloride, barium chloride, potassium chloride, bismuth chloride are made, by weight percentage, its chloride containing mercury 2.6%, zinc chloride 4%, barium chloride 3.5%, potassium chloride 3.5%, bismuth chloride 3.5%, water 0.27%, mechanical strength 95.6%, granularity 3~6mm(95%), bulk density 450g/l, mercury chloride burns mistake rate 0.89%, and concrete production technology is:
1,500 kilograms of the hydrochloric acid solutions that is 0.1~5% with high purity hydrochloric acid and desalted water preparation mass fraction, normal temperature is placed, standby;
2,100 kilograms of selected wood activated charcoals are put in the hydrochloric acid solution of step 1 preparation and soaked 20~60 minutes, use during this time circulating pump that hydrochloric acid solution is constantly flowed, then take out and filter or be filtered dry, under the temperature conditions of 200 ℃, be dried to moisture below 3% with centrifuge drying dehydration;
3, with mercury chloride, hydrochloric acid and desalted water preparation mass fraction be 2~5%, 500 kilograms of the mercury chloride hydrochloric acid solutions of pH=3, and by the weight ratio of contained other material of the ultralow mercury catalyst mercury chloride contained with it of preparation, add appropriate collaborative promoter zinc chloride, barium chloride, potassium chloride, bismuth chloride, standby;
4, to finally be dried to moisture active carbon below 3% through step 2 immersion puts in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 4~10 hours, use during this time circulating pump that mercury chloride hydrochloric acid solution is constantly flowed, then take out and filter or be filtered dry with centrifuge drying dehydration, put into baking oven, under the temperature conditions of 100~140 ℃, be dried to moisture below 0.3%, complete selected wood activated charcoal and adsorb for the first time mercury chloride work, then the active carbon that has adsorbed a mercury chloride is put into again in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 2~5 hours, and repeat to adsorb for the first time other operation in mercury chloride process, can complete selected wood activated charcoal and adsorb for the second time mercury chloride work, then again the active carbon that has adsorbed secondary mercury chloride is put into for the third time in the mercury chloride hydrochloric acid solution of step 3 preparation, under the temperature conditions of 50~98 ℃, soak 2~5 hours, and repeat to adsorb for the second time other operation in mercury chloride process, complete the work of three absorption mercury chloride of selected wood activated charcoal, make selected wood activated charcoal center absorption mercury chloride, the ultralow mercury catalyst making by weight percentage, chloride containing mercury 2.6%, zinc chloride 4%, barium chloride 3.5%, potassium chloride 3.5%, bismuth chloride 3.5%, water 0.27%, mechanical strength 95.6%, granularity 3~6mm(95%), bulk density 450g/l.
The high mercury catalyst that the ultralow mercury catalyst that this mercury chloride content that the embodiment of the present invention provides is 2.6% and existing mercury chloride content are 11.3% carries out the synthetic contrast test of vinyl chloride under equal operating condition:
1, test material: the high mercury catalyst that the mercury chloride content that the existing commonsense method of ultralow mercury catalyst that the mercury chloride content that the embodiment of the present invention provides is 2.6% makes is 11.3%
2, testing equipment: two shell-and-tube reactors of being made by triangular arranged by 15 φ 50 * 3500 tubulations (logical water quench between pipe)
3, test method:
(1) filling catalyst
Before filling catalyst, check that reactor is inside and outside without leak source, tubulation inwall is clean, dry, no-sundries; After opening catalyst packaging bag, be encased in immediately in each tubulation of reactor, filling catalyst will complete in 0.5h, guard against damp.
(2) preheating
Pass into the dry HCl of 90~100 ℃, speed control 7~8m
3/ h, continuous 8~10h, during every 2h, by reactor bottom, put acid once.
(3) by proportion control in 1:1.1~1:1.3(100% purity), the acetylene chlorine hydride mixed gas body that reaches more than 90 ℃ through preheat temperature passes into reactor, culture period 1 month, according to reactor cooling capacity, regulate acetylene gas intake, control temperature between 110~125 ℃; After culture period finishes, according to reactor cooling capacity, regulate acetylene gas intake (30~50h
-1), reaction temperature is controlled to 130 ℃.Each operating procedure of ultralow mercury catalyst that the mercury chloride content that uses the embodiment of the present invention to provide is 2.6% is identical with the high mercury catalyst that the mercury chloride content that uses existing commonsense method to make is 11.3%, and result of the test is in Table 1.
Table 1:
Test data from table 1, although the amount of the ultralow mercury catalyst chloride containing mercury that the embodiment of the present invention provides is ultralow, but the test various performances and existing high mercury catalyst the indifference that reflect, embody that mercury chloride occupies in activated carbon adsorptive capacity and the stronger center of reactivity, the wood activated charcoal of employing high voidage and add zinc chloride to make active carbon and mercury chloride give play to the huge measures such as synergy acetylene gas and hydrogen chloride gas are carried out to the strong concerted catalysis effect of addition reaction synthesizing chloroethylene; Stabilizing agent barium chloride, anti-coking agent potassium chloride add the improvement to catalyst mechanical performance.