KINETIC OF ESTERIFICATION OF CITRIC ACID IN PRODUCTION OF TRIALKYL CITRATES

Abstract

Polyvinyl chloride (PVC) is a body of a great many of composite materials and takes one of the leading places in thermoplastic polymers production capacity. Annual intake of PVC in the world (data of 2014 years) achieves to 35 mtpa. and has a consistent trend to further increase. PVC recycling is impossible without using of plasticizers. Nowdays scopes of use and plasticizers market used in the polymer materials production intended for contact with alimentary products, for medical equipment and children's toys production, are upon essential impact of policy statements of health, safety, security, environment. Plasticizers with citric acid – trialkyl citrates have needed properties: hazard class 4, high plasticize ability, full miscibility with polymer, high boiling and flash points, low volatility. The citric acid is available renewable raw produced from saccharified residues; world production volume is 1.6 mtpa. There are no local plasticizers production technologies with citric acid. Development of plasticizers production technologies with renewable raw material is relevant objective. Purpose of research is to create method of producing of trialkyl citrate, study of esterification regularities of citric acid with low molecular alcohol over different catalysts. In this research, the kinetic of performances of citric acid esterification by pentanol was estimated over different catalysts. Reaction orders were defined using three catalysts: sulphuric acid, orthophosphoric acid and p-toluene sulphonic acid. The rate constants and activation energies of esterification were found. Kinetic formulas were obtained. The time of esterification was defined to achieve 95 % conversion of citric acid. The time varies from 1.5 to 5 h depending on used catalyst. For citation:Sushkova S.V., Levanova S.V., Glazko I.L., Pavlova K.V. Kinetic of esterification of citric acid in production of trialkyl citrates. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N2. P. 74-78.