Abstract: Various fractions of petroleum, including residual oils and crude oils, are catalytically converted to produce gaseous olefins, especially propylene and butylene, in fluidized or moving bed or transfer line reactors with solid, acidic catalysts in the presence of steam at a temperature of 500.degree. to 650.degree. C. and a pressure of 1.5.times.10.sup.5 Pa to 3.times.10.sup.5 Pa, with a weight space velocity of 0.2 to 20 hr.sup.-1 and catalyst-to-oil ratio of 2 to 12. Spent catalyst is continuously removed from the reactor to a regenerator where the coke is burned off and the hot catalyst is returned to the reactor. In a comparison with conventional catalytic cracking and tubular furnance pyrolysis processes, it is found that the process of the present invention produces more propylene and butylene. The total yield of the process of the present invention is about 40 percent by weight of the feedstock.

Abstract: A class of pillared interlayered clay molecular sieves with large pore size were prepared by cross-linking the regularly interstratified mineral clay. Wherein the cross-linked rectorites possess an extraordinary thermal and hydrothermal stabilities. Said class of pillared interlayered clay molecular sieves are potential commercial catalysts for carbonium-ion type reactions, adsorbents and catalyst carriers.