碱金属盐及碱土金属盐改性的活性氧化铝催化作用下以甲醇为烷基化试剂的烷基酚, 烷氧基酚及其混合物的烷基化转化

Using methanol as the alkylation reagent, the alkylations of alkylphenol, alkoxyphenol, and their binary and five-component mixtures were investigated, under the catalysis of alkali (A) and alkaline-earth (AE) salts modified activated alumina (AA). The results showed that phenol and methylphenol can high efficiently be converted to O-alkylation products over A/AA. Specifically, under the catalysis of Cs2CO3/AA, the conversion rate of phenol reached to the highest value of 90.4%(ω) with high anisole selectivity of 96.1%(area). However, under the same reaction conditions, neither the conversion rate nor the product selectivity is satisfactory for the alkylation of methoxyphenol, and the adjustment of the reaction temperature, the space velocity, or the Cs loading amount cannot make the results better. There exists a strong synergistic effect for the co-alkylation of the alkylphenol/alkoxyphenol mixture, under this effect, the conversion of alkylphenol is inhibited, while the conversion of alkoxyphenol is promoted, with remarkably enhanced selectivity to C-alkylation products.