Adsorption Removal of Copper, Zinc and Cadmium in Aqueous Solutions and Road Runoff by Carbonized Mulch: Heavy Metal Removal by Carbonized Mulch

Abstract

Carbonized mulch (CM) was used to remove copper (Cu), zinc (Zn) and cadmium (Cd) in solutions and urban road runoff in this study. Parameters investigated included pH, sorbent amount and reaction time. The removal of all three metals by CM was determined by pH and the peak at pH 5.5. The adsorption kinetics of all three metals by CM could meet the pseudo-first-order equation. The adsorption isotherms of all three metals by CM could be greatly described by Langmuir equation, as well as by Freundlich equation. The peak uptakes were 30.8 mg Cu/ g CM, 69.9 mg Zn/ g CM and 27.5 mg Cd/ g CM. Obtained results indicate that CM could be used to deal with heavy metals in road runoff, although there are the influences of real runoff qualities (including light metal cations, anions e.g.).

A review of biochar as a low-cost adsorbent for aqueous heavy metal removal

“…Despite limitations of the pseudo first order model, this model has been successfully applied to describe the sorption kinetics of heavy metals on various biochar sorbents (Table 5). For instance, Zuo, et al (2012), reported that the pseudo-first order model closely reproduced data from the sorption of Cu, Cd, and Zn by carbonized mulch. Plotted kinetic curves for Cd, Zn, and Cu on the carbonized mulch, revealed a rapid sorption of these metals for the initial 30 min (typical for first order reactions).…”