A Study on H₂SO₄-Treated M x O y Catalysts for Styrenated Phenols by Alkylation of Phenol with Styrene.

Styrenated phenols (SPs) involving very small amount of unreacted phenol and high content of di-SP (DSP) were synthesized, which can be used to prepare SP alkoxylate. The solid catalyst was prepared by impregnation method. SO2-4 on SO2-4/MxOy catalyst was introduced from an aqueous 1M-H2SO4 solution. The catalysts were characterized by XRD patterns, and FT-IR spectra. The catalytic activity was examined by measuring conversion of phenol and styrene in a batch liquid-phase reactor. The concentration of phenol, styrene, and SPs were measured by GC with capillary column. The optimum synthesis conditions for concentration of sulfuric acid solution, catalyst amount of reactants, reaction temperature, and reaction time over SO2-4/ZrO2 catalyst were 15 wt%, 15 wt%, 100 °C, and 6 hr, respectively. At these conditions, conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 52.1%. On the other hand, the optimum synthesis conditions over SO2-4/TiO2 catalyst were 10 wt%, 5 wt%, 100 °C, and 1 hr, respectively, and conversion of both phenol and styrene were almost 100%, and the selectivity of DSP was 66.1%.