Absorption of metal elements from industrial and urban wastewater using sawdust and cotton linter

This study was conducted to evaluate the effect of some cellulosic materials such as sawdust and alphacellulose (cotton linter) for purification industrial and urban wastewater and their effects on the absorption of some elements (No3, Na, K) and heavy metals (Cd, Cr, Zn). Due to very low amounts of chromium, cadmium and nitrates in the wastewater samples, the chromium and cadmium chloride solution with a concentration of 20 ppm and sodium nitrate solution with a concentration of 60 ppm were used. The results showed that among the absorbents, mixture of wood sawdust and alpha-cellulose had the same effect on sodium and zinc absorption compared to sawdust. Absorbents did not affect the potassium uptake from wastewater, but had a significant effect on the absorption of chromium and cadmium. The amount of chromium in the control sample was 27 mgL-1 to 3.76 mgL-1 after exposure to the sawdust absorbent and 4.4 mgL-1 in the mixture of sawdust and linter absorbent. The amount of cadmium decreased from 22 mgL-1 in control sample to 1.5 mgL-1 (coefficient of 93.18%) after exposure to the mixed sawdust and alpha-cellulose and 0.88 mgL-1 in sawdust treatment (coefficient of 96%). Absorbents had also no significant effect on nitrate absorption in sodium nitrate solution.