Synthesis of Efficient TS-1 Zeolite for Selective Oxidation Reactions

Oxygenated organic molecules are important intermediates for synthesis of fine, agrochemical, and pharmaceutical chemicals. Conventional synthesis of oxygenated molecules through stoichiometric approach often lead to low selectivity and generation of large amount of wastes.[1] Oxidation of organic molecules by zeolite catalysts has gained attention because of their stability, selectivity, and tunable physicochemical features.[2] Isomorphous substitution of Si with Ti by Tarammaso et al., from Eni Company in 1983 resulted in microporous TS-1 catalyst with oxidation function with H2O2 as oxidant.[3] Despite of enormous research on TS-1 catalyst since its discovery, only a few reactions by this catalyst has been commercialized. This is because of high cost of synthesis, low yield, and generation of wastewater during synthesis of TS-1. In this study, we investigated synthesis of TS-1 by using different silica sources. The obtained TS-1 catalysts showed double yield of that of conventional one. Catalytic tests of hydroxylation of phenol to catechol and hydroquinone resulted in higher conversion than that of conventional one (Figure 1). The method of TS-1 synthesis developed here is a powerful alternative to make low-cost catalysts and promote industrial applications of TS-1 catalysts.