Comparison of Heavy Metal Adsorption by Activated Carbons Prepared from Cassava and Bamboo Biomass
Authors: Ijaola OO, Omotosho OA
The utilization of cassava peels and waste bamboo as precursors for producing activated carbon for the adsorption of zinc (Zn2+), nickel (Ni2+) and cadmium (Cd2+) from agricultural wastewater was investigated in this study. The biomass materials (cassava peels and waste bamboo) were carbonized at temperature range of 200 oC- 420 oC for a period of 90 min and 120 min for cassava peel and waste bamboo respectively. Activation with ZnCl2 was done at impregnation percentage of 0, 33.3 and 66.6% for cassava peel carbon while 0, 10 and 20% was used for waste bamboo. The scanning electronic micrograph (SEM.EVO/MA15) was used to view the morphology of each adsorbent tested. The pH of adsorbents used was also studied based on impregnation ratio. pH of each adsorbent used increased with increase in impregnation percentage with bamboo activated carbon having a high pH value range of 6.8-7.2 as compare to cassava peel with 5.3-5.4 pH value. The pore space and surface area for impregnation percent of 66.6 and 20% for cassava adsorbent and bamboo adsorbent respectively had a combination of mesopores and macropores with prevalence of macropores indicating that higher percentage of ZnCl2 increased the pore space. The cassava peel impregnated at 66.6% showed a greater removal efficiency of 66.67% for Ni2+ when compared to waste bamboo impregnated at 20% which has 100% adsorption efficiency for Ni2+. Adsorption efficiency of other metals studied for both adsorbents fell in the range of 50-99%.
Affiliations: Department of Civil Engineering, Faculty of Engineering, Federal University Otuoke, Otuoke, Bayelsa State, Nigeria.
Keywords: Heavy Metals, Zinc Chloride, Adsorption, Cassava Activated Carbon, Bamboo Activated Carbon
Published date: 2020/12/30