Mercaptan e.g. methyl mercaptan, capturing method for use during deacidification of natural gas, involves circulating purge gas across molecular sieve to obtain gas that is contacted with solvent so that mercaptans are absorbed by solvent

摘要

#CMT# #/CMT# The method involves circulating a natural gas across a molecular sieve (T1) e.g. 13x-type zeolite, absorbing mercaptans contained in the gas to obtain a natural gas impoverished of mercaptans. A purge gas is circulated across the sieve charged with mercaptans to desorb the mercaptans from the sieve and to obtain a purge gas enriched with the mercaptans. The enriched purge gas is contacted with a solvent having olefins and an acid catalyst e.g. sulphuric acid, such that the mercaptans are absorbed by the solvent and react with the olefins for forming sulphides. The purge gas is then evacuated. #CMT#USE : #/CMT# Used for capturing mercaptans e.g. methyl mercaptans, ethyl mercaptans and propyl mercaptans, contained in a natural gas during deacidification of the natural gas and for subsequent dehydration and gasoline stripping stages (claimed). #CMT#ADVANTAGE : #/CMT# The method allows eliminating the mercaptans contained in the natural gas in an efficient and economic manner. The method ensures the chemical reaction between the mercaptans and the olefin contained in the solvent having strong absorption capacity, thus minimizing the capacity of solvent necessary for the extraction of the mercaptan while ensuring optimal hydraulics for the gas-liquid contact. #CMT#DESCRIPTION OF DRAWINGS : #/CMT# The drawing shows a mercaptan capturing method. DA : Deacidification unit DH : Dehydration unit T : Absorption unit T1, T2 : Molecular sieves 2 : Conduit.