Abstract

Atef S. Alzaydien*

DOI : http://dx.doi.org/10.13005/ojc/310205

This paper deals with the application of wheat bran (WB), an agricultural by-product, for the adsorption of methyl orange (MO) from aqueous solution. The characteristics of WS surface, such as surface functional groups, zero of point charge and conductivity were obtained. The removal of MO onto WB from aqueous solution was investigated by using parameters, such as pH, temperature, adsorbent dose and contact time. A spectrophotometer technique was used for measuring the extent of adsorption. The extent of dye removal decreased with increasing adsorbent dosage and also increased with increasing contact time and temperature. The results revealed that the sorption capacity increases from  12.34 to  19.85 mg/g when the temperature increased from 25 to 55 ^ﻩC. This suggests that the sorption of MO dye onto WB is endothermic and activated process indicating that the higher temperature is more favorable for the dye sorption. Optimum pH value for dye adsorption was determined to be 4.0. strong pH-dependence of MO adsorption onto WB together with FTIR results indicate to possible involvement of physical forces such as hydrogen bonding, Vander Waals and  covalent chemical bonds in the adsorption process. In addition, the adsorption data of MO by WB were applied to Lagergren^,s pseudo first-order, pseudo second-order and the rate constants of first-order adsorption (k₁ = 1.34x10² min^-1) the rate constants of second-order adsorption (k₂ = 2.93x10^-3 g/mgmin) were calculated, respectively.). The results indicate that WB could be employed as a low-cost alternative to other adsorbents in the removal of MO from aqueous solution.

Adsorption; WB; MO; Surface; pH; Temperature; Rate

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