Indian Journal of Chemical Technology Vo l. 10, September 2003, pp. 501-504 Articles High pressure epoxidation of soyabean oil D Ratna•§, S K Srivastavab & Ajit K Banthia 3 * •Materi als Science Centre, t>oepartment of Chemistry, lndian Institute of Technology, Kharagpur 721 302. India Received 8 February 2002; revised received 5 March 2003; accepted 29 April 2003 The effects of various process high pressure epoDdatioa of soyabeao oil ban beal studied. It was observed that high epoxy yield can be obtained by optimizing the proc::as parameters like temperature, pressure etc. was fowia to ' bave significant effect on epoxy yield. Epoxy.yidd inaeasc:s linearly with pressure and becomes constant.at'aboot· 2Q MPa. Optimum temperature was fouod to be lOO"C above which the epoxy yield decreases. FfiR indic:ates ring opening side radion at bigber tempenture. It was also found that the epoxy yield ciiJ. to CHP ratio reducal beyond 10. Epoxidation, an important route of chemical modification of unsaturated oils (triglycerides) and polymers, has emerged as an active field of research because of improved properties and technological importance of epoxidized products 1 .2 . The epoxidation products of unsaturated oils like soyabean oil are widely used as plasticizer for rigid polymers e.g. polyvinyl chloride (PVC), stabilizer for halogen containing polymer e.g. PVC, chlorinated rubber, etc. and as toughening agents for PVC and epoxides 3 .4. In order to use the epoxidized oil as a toughening agent. it is essential to control its epoxy content. Formation of -OH groups by ring opening side reaction is undesirable as the -OH groups increase the solubility parameter of the epoxidized oil and increases the mi scibility with the polymers like epoxy and PVC. For successful use of a modifier as a toughening agent, it should have borderline miscibility with the base polymer 5 · 6 . The commercial process, which is widely used for epoxidation, is conventional in situ per acid method 7 . 10 . However, in the aforesaid process the progress of reaction is slow due to the phase transfer phenomena and there also exists a possibility of ring opening side reaction at high temperature. Recently a new method has been reported for high pressure epoxidation of unsaturated compounds using soluble hydroperoxide in presence of MoS 2 as a heterogeneous catalyst''. The choice of MoS 2 as a catalyst was mainly due to the fact that it was proven *For correspondence (E-mail: abanthia@hotrnail.com; Fax: 03222-255303) §Present address: Naval Materials Research Laboratory, Addl Ambemath, Thane 421 506, India against sulphur poisoning 1 2. 13 • Being a heterogeneous catalyst. it offers the advantages both in terms of catalyst reuse and end-product purity. In the present paper, the detailed optimization of process parameters like temperature, pressure, catalyst concentration and oil to hydroperoxide ratio for the high pressure epoxidation process of soyabean oil are discussed. Experimental Procedure Materials Soyabean oil used was of industrial grade (Gawalior Oil Ltd, India). HBr in acetic acid (E. Merk, India) and 2,4-dibutyl phenol (S.D. Fine Chern., India) were used as received. Cumene hydro- peroxide (CHP/Aldrich) was used as an oxidant. The solvents namely chlorofon:n., acetic acid, chloro- benzene, etc. were of analytical grade (BDH, India). Preparolion of MoSz catalyst turd its chtuacteri:odion MoS 3 was used as a base material for the preparation of catalyst 14 • It was prepared by the thermal decomposition in argon atmosphere at goooc for 20 h. The physicochemical properties of the catalyst are shown in Table 1. High pressure IUIIoclaPe A high pressure autoclave (High Pressure Equipment Co., USA) of 300 mL capacity, having an angular play of 15° with 30 oscillations per min was used. The autoclave was electrically heated and the temperature was controlled by a temperature controller, the details of which have already been reported elsewhere 15 " 16 •