| Ester quaternary ammonium salt (EQ) as an excellent biodegradable cationic surfactant, has been widely used in textile, printing and dyeing, leather, synthetic fiber, paper making and machinery industries, which is a typical kind of"green softener". However, some defects, existing in the production process of EQ, cause the product quality and preparation process should be improved. Further more, quaternary ammonium agent used in the production process of EQ was toxic, which should be improved too. Dimethyl carbonate (DMC), which is a kind of green reagent, has received much attention in recent years. The molecule of DMC containing methyl group can be used as a new type of quaternization agent. This article mainly investigated the green improvement of EQ preparation process and the application of dimethyl carbonate as a quaternization agent, which would lay the foundation for the application of dimethyl carbonate in the preparation of green cationic surfactant.Loop reactor process had been developed to prepare esteramine, and the high quality of esteramine was successfully synthesized. Compared with the conventional stirred tank process under the optimal experimental conditions, the results showed that the loop reactor process not only had higher heat and mass transfer efficiency with 1/3 reaction time being shortened and low consumption of energy and nitrogen, but also obtained higher quality and lighter color of the products. Further more, there was no emission in the reaction process.To overcome the problems for the homogenous catalysts that catalysts remained in the products and can not be reused, and improve the selectivity of esteramine, zirconium sulfate (ZS) supported on SBA-15 mesoporous molecular sieve solid acid catalyst (ZS/SBA-15) were developed for esteramine synthesis. In comparison with the traditional catalyst, ZS/SBA-15 showed better catalytic activity and selectivity. When 20%ZS/SBA-15(6) was taken as the catalyst of esteramine synthesis, it not only could improve the conversion of raw materials, but also increased the content of mono-esteramine and di-esteramine. Moreover, this kind of improvement could solve the catalyst residues and be reused effectively, and benefit the intrinsic quality of ester amine products.The quaternization of DMC and esteramine was studied. The reaction conditions were optimized by orthogonal test method. The characterization results of 1H-NMR indicated that the new green EQDMC (Di-alkyl diester hyroxylethyl methyl ammonium methyl carbonate) was synthesized successfully. Excessive dimethyl carbonate and the solvent could be recovered and recycled without any extra-treatment. EQDMC could replace the traditional softener as a new green softener.The quaternization reaction conditions of dimethyl carbonate and alkyl tertiary amine with different carbon chain lengths of single and double were also optimized. The results showed that: the reaction rate and conversion of the single alkyl tertiary amine had nothing to do with the carbon chain length at the same reaction conditions, and the conversions were about 99%, but the reaction rate and conversion of dual alkyl tertiary amine had a lot to do with carbon chain lengths, and the reaction rate slowed with the longer carbon chain. Based on the molecular space structure simulations, a conclusion was drawn that the difference was mainly due to the space steric hindrance.At the same time, 1831 was synthesized by the reaction of quaternary ammonium salt methyl carbonate and hydrochloric acid, which proved that quaternary ammonium methyl carbonate could be used as the materials of preparing various counter ion of quaternary ammonium salts. During this, a pre-test foundation has been built for enriching the types of quaternary ammonium salts.
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