fast and effective removal of cadmium and lead ions from aqueous environments using dithizone-modified mesoporous cellulose acetate

With the rapid industrial development, environmental pollution due to discharging trace metals into rivers and marine waters is getting worse. lead and cadmium are two such trace metals enter into the environment. existence these two trace metals at hazardous levels in water may attend to accumulate in living bodies thorough the food chain. several techniques have been applied for the removal of lead and cadmium ions from wastewater such as chemical precipitation, coagulation-flocculation, ion exchange, adsorption, evaporation, biosorption and membrane filtration [1]. nowadays, nano-adsorption techniques have been extended for water treatment. these techniques have some advantages over traditional treatment methods such as high area to volume ratio, flexibility to modify, selectivity, and feasibility to remove trace quantities of hazardous metals. nanotechnology and nanoparticles are increasingly recognized for their potential applications in different branches of science. in the recent years, nanoparticles-based solid phase extraction (spe) offers great possibilities for development of new analytical methodology, because of their unique properties, such as their large surface areas and high adsorption capacity. cellulose acetate (ca) adsorbent derivatives like silver‐loaded ca hollow fiber membranes, ca/polyethyleneimine blend microfiltration membranes, epoxy functionalized poly (ether-sulfone) incorporated ca ultrafiltration membranes, and so on have been recently applied to eliminate noxious compounds from water [2, 3]. the objective of the present study was to investigate the adsorption of lead and cadmium ions onto cellulose acetate mesoporous modified with dithizone, an agent that can form strong complexes with lead and cadmium ions. in this regard, a sorbent based on cellulose nanosponges modified with dithizone was prepared and characterized using various instrumental techniques. in this method, the batch removal process were designed by response surface methodology (rsm) based on a central composite design (ccd) model. under the optimized conditions, the removal efficiency of metal ions were > 90 % at ph of 5.5, and maximum adsorption capacities of investigated ions was above 150 mg/g. adsorption data showed that investigated ions uptake on ca@dithizone followed the langmuir isotherm model equation and pseudo-second order kinetic model. the proposed method was successfully used to remove the cadmium and lead ions from some environmental water samples and satisfactory results was achieved.