Response surface methodology (RSM) modeling to improve removal of Cr (VI) ions from tannery wastewater using sulfated carboxymethyl cellulose nanofilter

Abstract

Sulfated carboxymethyl cellulose nanofilter membrane by crosslinking of glutaradehyde (GA) supported on polysulfone membrane (SCMC-GA-NF) was prepared and characterized by FTIR, XRD, SEM and EDS. The modeling of Cr (VI) removal from tannery industries wastewater by utilizing synthesized SCMC-GA-NF was studied by response surface methodology. The initial pH (4,8,12), pressure (2, 4, 6 bar) and SO3/Pyridine:CMC ratio (1:1, 2:1, 3:1) in filter were selected as independent variables in box behnken design while Cr(VI) removal % was considered as the response function. The maximum Cr(VI) removal efficiency of 79.85% was obtained at pH = 4, pressure = 3 bar and SO3/Pyridine:CMC ratio (1:1) in filter. The reusability of SCMC-GA-NF was found to be suitable. The current study indicated that the prepared SCMC-GA-NF is an efficient filter for removal of Cr(VI) from aqueous solutions.