Trans-1, 2-dichloroethylene is a kind of next generation chlorinated solvent which can be widely used in precision electronic instrument cleaning. Compared with traditional chlorinated and brominated solvents, trans-1, 2-dichloroethylene is safe for human health and more friendly to environmental characteristics.     At present, the production methods of trans-1, 2-dichloroethylene in the market are mainly as follows: (1) Trans-1, 2-dichloroethylene May be obtained by dechlorination of 1, 1, 2, 2-tetrachloroethane by zinc powder or iron powder, or by cracking of 1, 1, 2-trichloroethane by copper chloride on pumice stone. However, no industrial production has been reported for either method. (2) US patents us20070191653 and us7335806 and world patent wo2007094965 have reported the preparation of trans 1, 2-dichloroethane. The patent is the reaction of 1, 2-dichloroethane with chlorine gas under the action of oxychlorination catalyst to obtain 1, 2-trichloroethane, 1, 2-trichloroethane under the action of oxychlorination catalyst dechlorination to prepare a mixture of dichloroethylene, and then through conventional distillation to obtain a single dichloroethylene product. However, the route of this process is long and the production cost is high. (3) Chinese patent cn101353289 discloses a method for extracting trans-1, 2-dichloroethylene from low trope produced by gas phase catalysis. This method deacidizes and dehydrates the low-boiling material, and then distills the product. Although this method can realize waste utilization and reduce environmental pollution, it is greatly affected by trichloroethylene output.     In view of the problems and shortcomings of the existing technology, our company's technical staff developed a new technical scheme for the production of trans-1, 2-dichloroethylene, which has the advantages of simple process, simple separation and purification. The technical scheme is as follows: Cis-1, 2-dichloroethylene was isomerized under the action of translocation catalyst to obtain trans-1, 2-dichloroethylene. The reaction temperature was 150 ~ 250℃, the residence time was 0.5 ~ 5s, and the reaction pressure was normal pressure. The product was purified by distillation to obtain trans-1, 2-dichloroethylene. The translocation catalyst was AL2O3 as the main catalyst, and metal additives were added to the main catalyst, among which the metal additives accounted for 0.5% ~ 5%. The metal additive is one of ti, cr, fe, ni and zn.   The reaction temperature ranges from 180 ℃ to 230℃, and the reaction temperature has a great effect on the performance of the converted catalyst. If the reaction temperature is too high, the conversion rate of cis-1, 2-dichloroethylene will increase, but the selectivity of trans-1, 2-dichloroethylene will decrease and the impurity content will increase, which will affect the subsequent separation and increase the requirements for equipment. When the reaction temperature is too low, the conversion rate of cis-1, 2-dichloroethylene is low, and the one-way yield decreases.   When the residence time is 1 ~ 3s, the residence time will affect the performance of the conversion catalyst. With short residence time, the conversion rate of cis-1, 2-dichloroethylene decreases. At the same time, due to the impact of air flow on the conversion catalyst, the loss of active ingredients in the conversion catalyst also increases. With long residence time, the selectivity of trans -1, 2-dichloroethylene decreases and the impurity content increases, which affects the subsequent separation.     The transposition catalyst used in the invention makes 1, 2-dichloroethylene cis-trans isomerization, the process is simple, the product is easy to separate and purify, and the generated crude product can be obtained after the operation of rectification and purification. The invention can be performed in a conventional cracking reactor, such as a tubular reactor commonly used in prior art.

The development of oil chemical industry and biodiesel industry has caused a large amount of excess glycerin as a by-product. It has become a hot research and development area of oil chemical industry to develop deep processing products of glycerin and improve the added value of glycerin. Glycerol carbonate is an important link in the downstream product chain of glycerol, and its molecule is bipolar structure. It can not only be used as a new multifunctional synthetic material to synthesize downstream derivatives, but also as a component for the preparation of surfactants and stain remover, as well as an important solvent in the coating industry, which has very considerable industrial application value.   At present, the synthesis methods of glycerol carbonate mainly include phosgene, carbonylation, urea alcoholysis and transesterification, etc. The conversion rate and selectivity of glycerol carbonate have different degrees of problems. In the synthesis of glycerol carbonate, the yield of Glycerol carbonate and the conversion of glycerol are important indicators to evaluate the quality of the synthesis process. Gas chromatography is widely used at home and abroad for analysis, but the conventional treatment before the analysis is to purify the synthesized crude Glycerol carbonate first (remove the catalyst and evaporate the excess reaction solvent). However, it is inevitable that some components in the product will be lost in the purification process, thus affecting the accuracy of the analysis results. The laboratory staff of our company determined the contents of Glycerol carbonate and glycerol in crude glycerol carbonate products by gas chromatography, which improved the simplicity and accuracy of the analysis and was a supplement to the theoretical research of glycerol carbonate.

The global demand for triglyceride grows at a rate of nearly 10%, and the consumption of triglyceride reached nearly 4 million tons in 2010. China is a big consumer of triglyceride products, and a large amount of imports are needed every year to make up for the gap in domestic production. Glycerin carbonate (gc) can be used as a highly polar solvent or valuable polymer intermediate component, is the preparation of surfactants, clothes, detergent, new coatings, but also a new gas separation membrane and an important part of polyurethane foam particles, glycerin carbonate is also a good cosmetic moisturizer and drug carrier solvent and emulsifier. It is very versatile.   At present, the synthesis methods of glycerol carbonate mainly include phosgene, carbonylation, urea alcoholysis and transesterification, etc. However, the conversion and selectivity of glycerol carbonate have problems to varying degrees. Moreover, there is no large-scale industrial production of glycerol carbonate in China, which mainly relies on imports.   Us patent us2446145 and Japanese patent jp6009610 describe the synthesis of glycerol carbonate with phosgene, phosgene is a serious drug, and a large amount of hydrogen chloride produced in the reaction process is very harmful to human body, easy to cause environmental pollution, and has been gradually phased out.   Us patent us6025504 and Chinese patent cn101811971b and cn102285957b describe the reaction of glycerin and urea as raw materials under the catalysis of metal oxides or in the presence of Lewis acid catalyst to generate glyceryl carbonate. The disadvantage is that the reaction generates a large amount of ammonia, which needs to be carried out under vacuum and requires high equipment requirements. At the same time, the catalyst used is difficult to separate from the product, resulting in the product quality is not high.   Chinese patent cn101287710a, cn101717338a and US patent us201828 describe the advantages of using glycerol and dimethyl carbonate to prepare glycerol carbonate, such as: The reaction conditions are mild, the by-product methanol is easy to get out and does not require high temperature and pressure. The disadvantages are low glycerol conversion rate, expensive catalyst, much heat energy consumption for distilling remaining raw materials, and low product purity.   In addition, Chinese colleges and universities have also begun to study the direct preparation of glycerol carbonate with carbon dioxide by using biodiesel - based crude glycerol as raw material under the action of supported tin - based catalyst.