Chelation and permeation of heavy metals using affinity membranes from cellulose acetate–chitosan blends

Abstract

Abstract Affinity membranes have attracted the attention of membrane researchers especially in the field of wastewater treatment specifically in removing heavy metals by chelation from aqueous solutions. In the present work, several membranes are made from either cellulose di-acetate (CA) or CA together with chitosan (CS) solutions, the CS prepared in our lab from shrimp shells or from readymade shrimp or crab shells. The variables investigated included type and ratio of solvents forming the casting solutions, mass ratio of CA to CS in the casting solution, type of CS (shrimp or crab shells), and initial concentration of Cu(II) ions. The membranes were fabricated by casting on a glass plate of a casting assembly using a surgical blade by the phase inversion technique. The permeation and adsorption capacity of each membrane were examined in a plexiglass two compartment diffusion cell in which the membrane was placed between the two compartments to separate the copper ion solution from an equal volume of di...