The heterogeneously catalyzed gas phase alkylation of m-cresol with methanol to 2,3,5-trimethylphenol, a precursor for vitamin E, on acidic zeolites and zirconium oxide-based catalysts was investigated. The influence of different acidic centers and of zeolites with different structure and Si/Al ratio was studied. The highest yield of 2,3,5-trimethylphenol (30 wt%) was obtained for the alkylation of 3,5-dimethylphenol on WO₃/t-ZrO₂ catalyst. In general, the activity of the catalysts can be enhanced if either reaction temperature or methanol to phenol derivate ratio are increased. However, at high degrees of conversion secondary and tertiary products are preferred. Based on the catalytic data it could be assumed that dimethyl ether is rather a side product than an intermediate in the alkylation of phenol derivatives, as expected from conversion of methanol to higher hydrocarbons (MtO and MtG). Comparing infrared spectroscopic data of pyridine adsorption with catalytic results, it could be concluded that Lewis acidic centers, e.g. on WO₃/t-ZrO₂, play a dominant role in the alkylation reaction. Zeolites, containing preferentially Brønsted acidic sites, were less active. The activity of the catalysts was independent of the texture properties.

的非均相催化气相烷基化米甲酚与甲醇-2,3,5-三甲基酚，对于维生素E的前体，在酸性沸石和氧化锆类催化剂进行了研究。研究了不同酸中心和不同结构和Si / Al比的沸石的影响。3,5-二甲基苯酚在WO ₃ / t -ZrO ₂上的烷基化反应获得2,3,5-三甲基苯酚的最高收率（30 wt％）催化剂。通常，如果提高反应温度或提高甲醇与苯酚衍生物的比例，则可以提高催化剂的活性。但是，在高转化率下，二级和三级产物是优选的。根据催化数据，可以假定二甲醚是副产物，而不是苯酚衍生物烷基化的中间体，这是甲醇转化为高级烃（MtO和MtG）所期望的。将吡啶吸附的红外光谱数据与催化结果进行比较，可以得出的结论是路易斯酸性中心，例如在WO ₃ / t -ZrO _2上在烷基化反应中起主要作用。优先包含布朗斯台德酸性位点的沸石活性较低。催化剂的活性与质地性质无关。