Olefin purification by adsorption of acetylenics and regeneration of adsorbent

A process for purification of olefins produced by thermal cracking of hydrocarbons which comprises:

• passing a gaseous mixture comprising at least about 99 percent by volume of an olefin having from 2 to about 4 carbon atoms, and acetylenic impurities having the same or similar carbon content in an amount in a range upward from about 1 to about 1000 parts per million by volume, through a particulate bed of adsorbent comprising predominantly a support material selected from the group alumina, silica, active carbon, clay and zeolites having surface area in a range of from about 10 to about 2,000 square meters per gram as measured by the BET gas adsorption method, on which is dispersed at least one metallic element in the zero valent state selected from the group consisting of copper, silver, iron, cobalt, nickel, zinc, ruthenium, palladium, and platinum, to provide an effluent stream from the bed;
• effecting, in the presence of an essentially dihydrogen-free atmosphere within the bed, selective and reversible adsorption and/or complexing of the contained acetylenic impurities with the adsorbent, until levels of the acetylenic impurities in the effluent stream increase to a limiting level in a range downward from about 1 parts per million by volume;
• and
• thereafter regenerating the resulting bed of adsorbent in the presence of a reducing gas comprising dihydrogen to effect release of the contained acetylenic impurities from the adsorbent.