Cation-exchange resin towards low-cost synthesis of high-performance TS-1 zeolites in the presence of alkali-metal ions
Abstract
Zeolite TS-1 is an important commercial catalyst for green production of oxyfunctionalized chemicals such as alcohols, ketones, epoxides, and oximes. However, the extremely high price greatly restricts its wide applications. In this paper, we developed a new route to synthesize highly active TS-1 zeolites by using low-cost tetrapropylammonium hydroxide (TPAOH) as a starting reagent that contains alkali-metal cations such as Na+ and K+ and is much cheaper than the high-purity TPAOH currently used in reported routes. The key point is the introduction of a cation-exchange resin into the synthetic system to capture the alkali-metal cations via ion exchange between the alkali-metal cations in the synthetic medium and protons in the resin, as well as adjusting the pH value of the TS-1 synthetic system. The present development shows great commercial potential and opens the possibility of preparing cheap TS-1 catalysts by using commercial TPAOH raw materials.