Crystalline aluminium silicate(s) prepn. - useful as catalysts for prodn. of aromatic cpds. from four-carbon mono:olefin(s) or hydrogen-carbon mon:oxide mixts.

摘要

Crystalline aluminium silicates are made which after calcining for 1 hour in air at 500 deg.C have the following properties: (a) thermally stable to above 600 deg.C; (b) X-ray powder diffraction pattern in which the four strongest lines are (as d(Angstroms)/relative intensity) 11.1 +/- 0.2, very strong; 10.0 +/- 0.2, very strong; 3.84 +/- 0.07, strong; and 3.72 +/- 0.06, strong; and (c) a formula, expressed in moles of oxides, of Al2O3/SiO2 of less than 0.05. The silicates are made by forming an aq. mixt. contg. one or more quat. alkylammonium cpds. R4NX; one or more Si cpds. which after drying at 120 deg.C and calcining at 500 deg.C gives a prod. with a SiO2 content of more than 90 wt.%; and one or more aluminium cpds. which after drying at 120 deg.C, produce a prod. with a content of elements other than Al, O or H of less than 1 wt.%. The molar ratios (R4N)20:SiO2 is 0.01-0.40; H2O:SiO2 is 5-65 and Al2O3:SiO2 is less than 0.05. The mixt. has an alkali metal (M) content such that M2O/Al2O3 is less than 0.2. The mixt. is maintained at an elevated temp. until the crystalline silicate is formed, and this is then recovered and calcined. The silicates are useful catalysts showing good activity and selectivity in the prodn. of aromatic hydrocarbon mixts. from C4 monoolefins or a hydrocarbon mixt. contg. more than 75 wt.% C4 monoolefins; and also in the prodn. of aromatic hydrocarbons from H2/CO mixts.