Epoxidation of styrene with molecular oxygen over binary layered double hydroxide catalysts

Binary layered double hydroxides (LDHs) of Mg–Al and Co–Al having varied cation molar ratio were studied for the catalytic epoxidation of styrene with molecular O2 as an oxidant and DMF as a solvent. The effect of various reaction variables, reconstruction and reuse of LDH samples on the catalytic activity was evaluated. The cation molar ratio of LDH as well as concentration of DMF significantly affected the catalytic activity. The highest styrene conversion was observed with LDH having cation molar ratio (Mg/Co:Al) of 3:1. Mg–Al LDH showed highest styrene conversion of 85% with 80% styrene oxide selectivity and Co–Al LDH sample exhibited highest styrene conversion of 97% with 83% oxide selectivity at 100 °C after 4 h.

Figure optionsDownload high-quality image (15 K)Download as PowerPoint slideHighlights
► Mg/Co–Al binary LDH solid base catalysts for styrene epoxidation with O2 in DMF.
► Significant affect of cation molar ratio on catalytic activity.
► Highest activity shown by cation molar ratio (Mg/Co:Al) of 3:1.
► Co–Al LDH showed higher activity and reusability than Mg–Al LDH.
► Activity increased by increasing DMF amount.