| 摘要 |
1,092,346. Molecular sieve process. ESSO RESEARCH & ENGINEERING CO. May 6, 1965 [May 13, 1964], No. 19161/65. Heading B1L. In a molecular sieve hydrocarbon separation process, the sieve is periodically desorbed with a displacing agent at elevated temperatures to obtain a hot displaced hydrocarbon stream, at least part of which is brought into contact with fresh hydrocarbon feed to form a mixture of the displaced hydrocarbon stream and the hydrocarbon feed which is at a temperature higher than that of the feed, the displacing agent is removed from the mixture and the mixture is recycled to the molecular sieve separation zone. In the embodiment of the drawing, hydrocarbon feed preheated at 2 is passed through sieve bed 3. Displacing agent preferably at the adsorption temperature is periodically passed through bed 3 from line 5. Part of the desorbate gas mixture is fed into tower 10 countercurrent to initial feed introduced at 11. Displacing agent is flashed off at the top of the tower at 10, and a combined desorbate - feed stream recycled by line 12 to heater 2. Part of the stream leaving tower 10 may be recycled to the tower via line 13 and heat exchanger 14. In an alternative embodiment there is cocurrent flow in the tower. Separation of various types of hydrocarbon from hydrocorbon mixtures and of sulphur compounds from light naphtha are referred to. Type A or type X sieves may be used. The displacing agent may be CO 2 , SO 2 , NH 3 (exemplified) C 1 - C 5 alcohols, glycols, halogenated hydrocarbons, nitro compounds, or amines of formula NR 1 R 2 R 3 where R 1 , R 2 , R 3 are C 1 - C 5 alkyl radicals. |
