Adsorption of Cr (VI) oxyanions onto modified wood pulp

A new adsorbent was prepared from wood pulp (WP) after reaction with epichlorohydrin and dimethylamine in the presence of pyridine and N,N-dimethylformamide (DMF). The adsorption of Cr (VI) from aqueous solutions by the so-prepared wood pulp adsorbent (WP-A) was investigated. Various factors affecting adsorption, such as pH, adsorbent concentration (1-5 g/L), agitation time (5-60 min), and Cr (VI) concentration (50-700), were taken into consideration. The adsorption of Cr (VI) onto (WP-A) was found to be pH-dependent and maximum adsorption was obtained at pH 3. The adsorption data obeyed Langmuir and Freundlich adsorption isotherms. The Langmuir adsorption capacity (Q(max)) was found to be 588.24 mg/g. Freundlich constants, K-F and n, were found to be 55.03 and 2.835, respectively.