Carbon molecular sieve and pellet compositions useful for C2-C3 alkane/alkene separations

US9579627B2 · kind B2 · utility

Assignee

• DOW GLOBAL TECHNOLOGIES LLC · US

Inventors

• Junqiang Liu · Manvel, US
• Mark K. Brayden · Denham Springs, US
• Edward M. Calverley · Midland, US
• Steven R. Lakso · Shepherd, US
• Yujun Liu · Ithaca, US
• Marcos V. Martinez · Freeport, US

Key dates

• Filing date: Mar 24, 2014
• Grant date: Feb 28, 2017
• Expiry date: Mar 24, 2034

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/17
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

A novel microporous carbon molecular sieve may be used as the basis for carbon adsorbent pellets that have discrete areas of carbonized binder and of carbonized precursor, macropores having an average pore diameter greater than or equal to 1 micrometer and a total macroporosity of at least 30 percent, both as measured by mercury porosimetry, and micropores that are capable of selectively admitting a C2-C3 alkene and excluding a C2-C3 alkane, and a total microporosity ranging from 10 percent to 30 percent. The pellets may be prepared by pyrolyzing a pellet structure comprising a carbon forming, non-melting binder and a non-porous gel type sulfonated polystyrene precursor at a temperature ranging from 500° C. to 1000° C., under an inert atmosphere and other conditions suitable to form the described pellets. The pellets are particularly useful in pressure swing and temperature swing adsorption processes to separate C2-C3 alkane/alkene mixtures.