title: Supported liquid membrane based removal of lead(II) and cadmium(II) from mixed feed: Conversion to solid waste by precipitation.
abstract: Simultaneous removal of two heavy metals, lead(II) and cadmium(II), from mixed feed using supported liquid membrane (SLM) based technique is investigated in this work. The carrier-solvent combination of "sodium salt of Di-2-ethylhexylphosphoric acid (D2EHPA) (4% w/w) in environmentally benign coconut oil" was immobilized into the pores of solid polymeric polyvinylidene fluoride (PVDF) support. Sodium carbonate (Na2CO3) was used as the stripping agent. Carbonate salts of lead(II) and cadmium(II) were formed in the stripping side interface and they were insoluble in water leading to precipitation inside the stripping solution. The transportation of solute is positively affected due to the precipitation. Lead(II) removal was found to be preferential due to its favorable electronic configuration. The conversion of the liquid waste to the solid one was added advantage for the final removal of hazardous heavy metals.
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology, Guwahati, Assam 781039, India.
authors.forename: Kamal Kumar
authors.initials: KK
authors.lastname: Bhatluri
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology, Guwahati, Assam 781039, India.
authors.forename: Mriganka Sekhar
authors.initials: MS
authors.lastname: Manna
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology, Guwahati, Assam 781039, India.
authors.forename: Aloke Kumar
authors.initials: AK
authors.lastname: Ghoshal
authors.affiliation: Department of Chemical Engineering, Indian Institute of Technology, Guwahati, Assam 781039, India. Electronic address: p.saha@iitg.ac.in.
authors.forename: Prabirkumar
authors.initials: P
authors.lastname: Saha
keywords: Environmentally benign solvent; Heavy metal; Metal precipitation; Mixed feed; Supported liquid membrane