Executive Summary : | Tight ultrafiltration (TUF) and loose nanofiltration (L-NF) membranes have attracted tremendous attention due to their potential applications in fractionation and resource recovery. Thickening of skin layer in TUF membrane and need of specially design monomers for interfacial polymerization (IP) process for the L-NF membranes are some limitations. Herein, we propose to fabricate TUF membrane by self-assembly of easily synthesized copolymer on UF membrane support. The L-NF membranes (polyester-polyamide layer) will be fabricated by the IP followed by selective degradation of esters bonds (construction degradation strategy). The advantages of the proposal are the tunable pore size and good permeation property by optimizing the packing of cross-linked micelles for TUF membranes. The pore size of the L-NF selective layer will be tuned by adjusting the proportion of the degradable ester linkages. Preliminary experiments strongly indicate very high feasibility of this proposal. Preliminary fabricated membranes show greater than 99% rejection of different dyes and less than 25% rejection of salts with water permeance of more than 30 L/m2/ h/bar. TUF and L-NF membranes with varying pore size will be fabricated and will be employed for the fractionation of simulated as well as real dye wastewater. Domestic size modules from the fabricated membranes will be prepared for the fractionation operation. |