Ultrafiltration of W/CO 2 Microemulsions in Ceramic Membranes
Abstract:Water‐in‐CO 2 (W/CO 2 ) reverse microemulsions stabilized with 1100 Da poly(ethylene glycol)‐poly(propylene glycol)‐poly(ethylene glycol) block copolymer were recovered using an ultrafiltration ceramic membrane in a custom high‐pressure cross‐flow separation unit. Viscosity‐corrected liquid CO 2 flux (298 K) through the membrane was investigated as a function of time and surfactant concentration to determine the cake layer mass transfer resistance. Rapid CO 2 flux decline was observed with increasing surfactant concentration, denoting cake layer buildup on the membrane surface. For instance, at 0.09 and 0.55 wt% surfactant, the ratio of cake resistance to membrane resistance was 0.4 and 3.8, respectively. Based on our previous work, the reverse‐micelles retain their aqueous core and are not altered during filtration. Ultimately, inorganic membrane separations can reduce energy consumption associated with compression/expansion cycles typically used in CO 2 ‐based processes.
Document Type: Research Article
Affiliations: 1: Department of Mechanical & Chemical Engineering, North Carolina Agricultural & Technical State University, Greensboro, NC, USA 2: Department of Mechanical & Chemical Engineering and NSF Science & Technology Center for Environmentally Responsible Solvents & Processes, North Carolina Agricultural & Technical State University, Greensboro, NC, USA
Publication date: January 1, 2006