ALKYLATION OF PHENOL WITH DIMETHYL CARBONATE OVER ALPO4, AL2O3 AND ALPO4-AL2O3 CATALYSTS

The vapor-phase catalytic alkylation of phenol with dimethyl carbonate over different AlPO4 (Al/P=1), Al2O3 and AlPO4-Al2O3 (5-25 wt.% Al2O3 ) catalysts produces anisole (O-alkylation) as the major reaction prod uct although o-cresol (C-alkylation) and methylanisoles were also foun d. The reaction is first order in phenol while O- and C-alkylation fol low parallel processes. As compared with methanol, DMC is far more eff ective as a methylating agent, and the methylation proceeds at a lower temperature and with higher O-alkylation selectivity.