| 摘要 |
1,242,741. Crystalline phosphate substituted aluminosilicates. MOBIL OIL CORP. 2 July, 1968 [5 July, 1967], No. 31477/68. Heading C1A. [Also in Division C5] A solid crystalline aluminosilicate identified by the code ZK-22 has the composition in its dehydrated form expressed in mol. ratios of oxides given by the expression wherein x is from 0.5 to less than 1, M is a positive ion other than tetramethylammonium (TMA), n is the valency of the ion, Y is 2 to 7 and Z is from 0.01 to (Y+2)/48, the aluminosilicate containing unexchangeable TMA ions in the as-synthesized form and being capable of selectively sorbing straight-chain hydrocarbons from an admixture with other hydrocarbons if the number of thermally stable cations per cube defined by the centres of eight adjoining truncated octahedral "sodalite cages" is 10 or less. The aluminosilicate is prepared in the sodium form (M=Na) by providing a reaction mixture containing sources of silicate, phosphate, phosphatoaluminate, hydroxyaluminate, TMA and sodium ions, the composition of the mixture expressed as mol. ratios selected within the ranges and so reacting said mixture as to produce the sodium form of ZK-22. By calcining ZK-22 the TMA ions may be replaced by hydrogen. If calcining is preceeded by ammonium exchange the hydrogen form of ZK-22 is obtained. The calcined and uncalcined forms may be subjected to base exchange, e.g. to give the lanthanum form. The process of preparation of the sodium form is similar to that employed in Specifications 1,060,224 and 1,151,953 but the proportions and conditions are modified to ensure inclusion of TMA ions within the crystal cages. |
