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Citrate plasticizer is a green series of new plasticizer, a traditional green alternative plasticizer DOP, received wide attention. Ionic liquids are a class of environmentally friendly as the esterification catalyst, Mannich reaction, Bechmann rearrangement and hydrolysis reaction has been widely used, has a high activity, high selectivity and can be recycled and so on. Carbon-based solid acid and other solid acid catalyst for its unique properties, excellent catalytic activity, high selectivity, has been widely applied to the acid-catalyzed chemical fields, these catalysts show a broad application prospects, become catalytic one of the hot research. This thesis focuses on the room-temperature ionic liquids, Coated solid acids and carbon-based solid acid catalyst for the development of three types of catalytic synthesis of environmental plasticizers in citrate application. First, we without solvent synthesized a series of low-temperature melting, less volatile sulfonic acid functionalized ionic liquids, and these ionic liquids for the catalytic synthesis of citric acid esters. The results showed that: the sulfonic acid type ionic liquid can be a good catalytic synthesis of citric acid ester plasticizers, having a high catalytic activity and stability, the optimum reaction time, the molar ratio of substrate and catalyst conditions, lemon ester esterification rate can reach 96%. Secondly, since the risk of economic interests and environmental protection requirements, require us to reduce the use of sulfuric acid, simplify the steps, which will be prompted us to develop a heterogeneous catalyst. First, the sol - gel method Coated silica catalyst, and the first to be used for the catalytic synthesis of tributyl citrate, the study found, parcel solid acid has high catalytic activity, with less, etc., but the cycle Xing bad. To solve this problem, we have developed a carbon-based solid acid, and its use of XRD, FT-IR, SEM and other means were characterized. Study found that carbon-based solid acid for its high catalytic activity, good thermal stability, can be recycled, etc. can be a good place to catalyze the synthesis of a catalyst such as sulfuric acid ester of citric acid, and the catalyst can be easily recovered, making the entire reaction economic, environmental friendly. Under optimal conditions, TBC esterification rate can reach 98%, and the catalyst circulation for five times TBC esterification rate decreased less than 2%. Finally, using the above catalyst, acylating agent, acetic anhydride Wei developed a simple and effective method of acetylation catalyst TBC, showing the mild reaction conditions, the reaction time is short, high yield and selectivity, etc., in the absence of solvent The reaction time is less than 30 minutes under the conditions, acetyl tributyl citrate closing rate of 97%.
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