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The liquid phase alkylation of catechol with tert-butyl alcohol to produce 4-tert-butyl catechol(4-TBC)was carried out over MCM-41,HZSM-5,H-exchanged montmorillonite and novel acidic porous montmorillonite heterostructures(PMHs).Upon all catalysts tested,4-TBC is the main product and 3-tert-butyl catechol(3-TBC)and 3,5-di-tert-butyl catechol are the side products.The synthetic PMHs showed higher conversion of catechol and better selectivity to 4-TBC compared to other solid acid catalysts tested.Over the PMHs derived from H-exchanged montmorillonite through template extraction processes,the suitable reaction temperature is ca 410 K,the ratio of catechol to tert-butyl alcohol is 1:2.Increasing the amount of catalyst(lower weight hourly space velocity)can improve the conversion of catechol and influence the selectivity slightly.The reasonable reaction time is ca 8 h.The type and strength of acidity of H-montmorillonite and PMH were determined by pyridine adsorption FT-IR and ammonia temperature-programmed desorption techniques.The medium and strong acid sites are conducive to producing 4-TBC and the weak acid sites to facilitating the 3-TBC formation.The differences between the PMHs from calcination and those from extraction are attributed to proton migration and acidity change in the gallery surface.