SYNTHESIS OF METHYL-t-BUTYL ETHER FROM METHANOL AND ISOBUTENE USING A CLAY CATALYST

-The acid-catalyzed reaction between methanol and isobutene to give methyl-t-butyl ether may be carried out using a cation-exchanged smectite as the catalyst. In 1,4-dioxan solvent at 60~ smectites exchanged with A13+, Fe 3+, or C# + give yields of -60% after 4 hr, whereas smectites exchanged with Cu 2+, Pb 2+, Ni 2+, Co 2+, Ca 2+, and Na + give less than -8% yield. The reaction is efficient only when certain solvents are used, e.g., with Ala+-smectite the yield is -5% when using 1,2-dimethoxyethane, diethyleneglycol diethylether, u-pentane, tetrahydropyran, N-methylmorpholine, or tetrahydrofuran solvents compared with -60% using 1,4-dioxan solvent (4 hr). Moreover, the effective solvents depend somewhat on the clay interlayer cation. The use of tetrahydrofuran and tetrahydropyran gives -35% yields at 6WC (4 hr) with Fe 3+or Cra+-smectites but -4% yield with A13+-smectite. Key Words--Catalysis, Methyl-t-butyl ether, Smectite.