GB1004741A - Process for the purification of gases - Google Patents

Abstract

Inert gases, e.g. nitrogen, argon, are purified by adding a reactant before or after compression of the gas to react with the impurities to form water, catalytically reacting the mixture and removing water with a desiccant, the heat of compression being used to simultaneously regenerate desiccant. The desiccant may be alumina or silica gel and the catalyst may be e.g. palladium "promoted" on pelleted alumina. The gas, containing say oxygen impurity, with the requisite amount of added hydrogen enters at 13 and is compressed in compressor 14 so that it leaves as a hot gas and enters the catalyst reaction chamber 12. Part or all of the hot gas leaving the compressor by-passes the catalyst chamber 12 through valves 17, 18 and passes upwardly through drier 11 to remove moisture retained by the alumina therein. The moist gas from 11 then passes through valve 19 to catalyst chamber 12 whence it is passed to water cooler 20 to condense part of the water which is collected in vessel 21, and proceeds through 21 and valve 22 to operating drier 10. The dried and purified gas leaves through valve 23. When regeneration of alumina in drier 11 is complete, valve 17 is closed and valve 24 is opened to by-pass the hot gas from compressor 14 through water cooler 26. The cooled gas passes <PICT:1004741/C1/1> through valve 18 and upwardly through drier 11 to cool the alumina therein. After the alumina has cooled, valves 18, 19, 22, 23, 24 are closed and valve 17 opened so that the drier 10 is regenerated and drier 11 operated. Alumina in drier 10 is cooled by closing valve 17 and opening valve 24. In an alternative method, two catalyst vessels in series and two driers are used.