Today, the major production techniques of Trichloroethene consist of acetylene technique, ethylene straight chlorination method, ethylene oxychlorination approach, and so on. According to the details, trichlorethylene can additionally be taken advantage of to develop a variety of things such as plastic chloride, dichlorethylene, trichlorethylene, tetrachloroethane, in addition to dichloroethane via the consolidated procedure of cozy chlorination, cool chlorination, in addition to oxychlorination of ethylene., can realistically make use of sources and decrease by-products. Additionally, trichlorethylene can similarly be produced through gas-phase catalytic dehydrochlorination of tetrachlorethylene. This technique can do away with the exhaust of saponification residues, significantly reduce the environmental pollution of organochlorines, as well as produce hydrochloric acid spin-off.
1. Acetylene Method
( 1) Saponification method
Using anhydrous ferric chloride as a driver, the addition reaction of acetylene and also chlorine under reduced pressure generates tetrachloroethane, which reacts with milk of lime to produce trichlorethylene and also calcium chloride. The produced trichlorethylene is azeotropically vaporized with water, and additionally the lowered boiling problem as well as also high boiling issue are eliminated by correction in the reduced steaming tower and also the high boiling tower to get the trichlorethylene item. The saponification treatment is straightforward, yet the amount of saponification down payment is significant. Every 1 ton of trichlorethylene things generated will create 5 to 8 tons of saponification residue, which positions great tension on environmental protection. Because of that, new trichlorethylene plants in China no more usage saponification. method to produce Trichloroethene items.
( 2) Gas stage catalytic dehydrochlorination technique
Currently, the freshly built factories in China that produce Trichloroethene gadgets handle the gas-phase dehydrochlorination procedure. This method gasifies tetrachloroethane, and at 200 to 290 ° C, the tetrachloroethane gas enters into a fixed-bed activator got ready with a chauffeur. Tetrachloroethane is dehydrochlorinated to produce unrefined trichlorethylene, in addition to a small amount of pentachloroethane is likewise exchanged tetrachlorethylene. After the catalysts are dehydrochlorinated, they are shared numerous towers to obtain the completed thing trichlorethylene. The reaction formula is as follows:
C2H2 + 2Cl2 → CHCl2CHCl2
CHCl2CHCl2 + Cl2 → CHCl2CCl3 + HCl
CHCl2CHCl2 + Cl2 → CHCl2CCl3 + HCl
CHCl2CCl3 → CCl2= CCl2 + HCl
2. Straight Chlorination of Ethylene
The straight chlorination method of ethylene is to react ethylene along with chlorine in a dichloroethane alternative of ferric chloride chauffeur to establish 1,2-dichloroethane, which is further chlorinated to develop a mix of trichlorethylene along with tetrachlorethylene, which reacts in It is completed at heat of 280 ~ 450 ℃, and then with distillation, ammonia neutralization, cleaning and drying out, trichlorethylene in addition to tetrachlorethylene products are gotten respectively.
3. Ethylene Oxychlorination Approach
The ethylene oxychlorination technique is to add ethylene as well as also chlorine to 1,2-dichloroethane, then include a catalyst and afterwards do an oxychlorination response with chlorine as well as additionally oxygen. The reaction temperature degree is 425 ° C. The item is cooled, cleansed with water, dried and also distilled. Trichloroethene as well as also tetrachlorethylene are divided. The action formula is as adheres to:
C2H2 + Cl2 → ClCH2CH2Cl
8ClCH2CH2Cl + 6Cl2 + 7O2 → 4ClCH= CCl2 + 4CCl2= CCl2 + 14H2O