process for the purification of crude oil to adsorb methane adiabatic pressure fluctuating

摘要

Crude CH4 contaminated with water, 15 vol.% 2-5C hydrocarbons, 5 vol. % CO2 and 1 vol. % 6+C hydro-carbons, is purified by adiabatic adsorption under changing press. by a process in which (a) adsorbent in impurity-adsorption zone is a SiO2 gel, pref. having surface 740 m2/g, av. pore dia. 22 A Degrees, porosity 46-49% and particle dia. 3.3 mm, and (b) selective adsorption takes place at 10-66 (21-38) degrees C under absolute press. 6.3-25.5 (8.05-16.8) kp/cm2. Process is used for CH4 recovery from natural gas, for use in prepn. of ethylene oxide, fluorohydrocarbons, CS2 and HCN. Over 99% pure CH4 can be recovered cheaply, opt. on small or moderate scale. SiO2 has high differential loading capacity for all impurities to be removed. The waste gas is enriched with impurities; the bed is easily desorbed with a scrubbing gas under low press.