S. H. Adam

Utilization of bivalve shell-treated Zea mays L. (maize) husk leaf as a low-cost biosorbent for enhanced adsorption of malachite green

In this work, two low-cost wastes, bivalve shell (BS) and Zea mays L. husk leaf (ZHL), were investigated to adsorb malachite green (MG) from aqueous solutions. The ZHL was treated with calcined BS to give the BS-ZHL, and its ability to adsorb MG was compared with untreated ZHL, calcined BS and Ca(OH)(2)-treated ZHL under several different conditions: pH (2-8), adsorbent dosage (0.25-2.5 g L(-1)), contact time (10-30 min), initial MG concentration (10-200 mg L(-1)) and temperature (303-323 K). The equilibrium studies indicated that the experimental data were in agreement with the Langmuir isotherm model. The use of 2.5 g L(-1) BS-ZHL resulted in the nearly complete removal of 200 mg L(-1) of MG with a maximum adsorption capacity of 81.5 mg g(-1) after 30 min of contact time at pH 6 and 323 K. The results indicated that the BS-ZHL can be used to effectively remove MG from aqueous media.

Novel removal of water-insoluble disperse dye onto a low-cost adsorbent prepared from tropical fruit waste

Abstract The potential of tropical fruit waste (durio zibethinus husk, DZH) as a low-cost adsorbent for removal of disperse blue 60 (DB 60) from an aqueous medium was studied under various conditions such as effects of adsorbent surface modification, contact time, pH, and temperature. The removal percentage of DB 60 was enhanced by approximately a factor of six when using the DZH treated by mineral acid compared to the untreated DZH. The functional groups of DZH before and after acid treatment were analyzed by Fourier transform infrared spectroscopy to elucidate these results. The surface structure of the DZH before and after adsorption was analyzed by field emission scanning electron microscopy. Adsorption equilibrium isotherms and kinetics of the DZH were studied using Langmuir and Freundlich models, as well as pseudo-first-order, second-order kinetic and intraparticle diffusion equations. The Langmuir isotherm model agreed well with the experimental data with a maximum adsorption capacity (q max) of 54...