Application of activated carbon supported cobalt(II) tetraaminophthalocyanine towards preparation of dimethyl disulfide

Abstract

Dimethyl disulfide (DMDS) is an important fine chemical that can be prepared by the refined Merox process of oxidation of sodium methyl mercaptide (SMM) in the presence of a catalyst. In this paper, a novel activated carbon (AC) supported cobalt(II) tetraaminophthalocyanine (AC-CoTAPc) catalyst was prepared by the chemical grafting method. EA, UV-vis, FT-IR, BET and XPS were used to characterize the structure of the new catalyst. The effects of reaction time, catalyst dosage, reaction temperature and oxygen pressure on SMM conversion per pass (CPP[Formula: see text], yield (Yield[Formula: see text] and purity of DMDS product (Purity[Formula: see text] were investigated to evaluate the catalytic performance of new AC-CoTAPc catalyst. The results show that free CoTAPc is easily dissolved in this DMDS product, which needs extra post treatment and cannot be reused. The supported catalyst AC-CoTAPc can easily solve these problems and can be properly reused four times to get Yield[Formula: see text] and CPP[Formula: see text] higher than 70% and 90%. Under optimum conditions, the Yield[Formula: see text] andCPP[Formula: see text] of the AC-CoTAPc catalyst could be as high as 87.4% and 98.1%, with a purity[Formula: see text]of DMDS product of above 99.9%. AC-CoTAPc exhibits better catalytic and reuse performance than the commercial AC-supported sulphonated cobalt(II) phthalocyanine (AC-CoPcS) catalyst and shows broad industrial application prospects.