Synthesis and study of hydrolyzed polyacrylamide grafted polyvinyl pyrrolidone (Hyd.PVP-g-PAM) as flocculant for removal of nanoparticles from aqueous system

摘要

This study investigates the real potential of synthesized hydrolyzed graft copolymer (Hyd.PVP-g-PAM) as flocculant in destabilization of aqueous suspension of nanoparticles (multi-walled carbon nanotubes or MWCNTs).A novel product (Hyd.PVP-g-PAM) has been synthesized by partial alkaline hydrolysis of a preformed graft copolymer of polyvinyl pyrrolidone (PVP-g-PAM). This novel product has much higher flocculation efficacy than the parent graft copolymer (PVP-g-PAM) as well as PVP, due to much larger radius of gyration as a consequence of straightening and uncoiling of the grafted chains. The flocculation competency of the product has been examined and compared with the PVP-g-PAM and with the commercial flocculant polyacrylamide (PAM) in coalfine and in aqueous suspensions of MWCNTs through standard jar test procedure. The result indicates that the synthesized flocculant has better flocculation efficacy than PAM. The optimal dosage as flocculant of synthesized product was at 1 ppm in MWCNT suspension whereas in coal-fine at 0.75 ppm.