HETEROPOLY ACIDS SUPPORTED ON ALPHA-AL2O3 AS SOLID ACID CATALYSTS FORMETHANOL TRANSFORMATION

Transformation of methanol into dimethyl ether and methane was carried out over two heteropoly acids supported on alpha-Al2O3 under atmosphe ric pressure and at 300-degrees-C. The samples were characterized phys icochemically (S(BET), X-ray diffraction and acidity). The effect of r eaction time, temperature, methanol partial pressure and of the conten t of the supported acid were studied. The results showed that alpha-Al 2O3 increased the catalyst life. The selectivity towards dimethyl ethe r and methane formation depended on the type of the acid and its conte nt. The results indicate that dimethyl ether is formed by surface reac tion whereas methane formation proceeds in the bulk of the catalyst.