243 JCHR (2020) 10(4), 243-252 Journal of Chemical Health Risks www.jchr.org ORIGINAL ARTICLE A Study on the Adsorption of Cadmium(II) from Aqueous Solution onto Activated Carbon Originated from Bombax ceiba Fruit Shell Rumpa Kundu, Chandramoni Biswas, Jamil Ahmed, Jannatul Naime, Mosummath Hosna Ara * Chemistry Discipline, Science Engineering and Technology School, Khulna University, Khulna, Bangladesh (Received: 7 July 2020 Accepted: 12 September 2020) KEYWORDS Adsorption; Activated carbon; Contamination; Batch studies ABSTRACT: Under the present study, the adsorption capability of the activated carbon originated from Bombax ceiba fruit shell was examined using batch experimental mode. Bombax ceiba fruit shell was carbonized and chemically activated using zinc chloride (ZnCl 2 ) as activating agent. The surface structure of the prepared activated carbon was examined by using scanning electron microscope (SEM). Some important experimental parameters namely pH of the solution, contact time and initial metal ion concentration in the solution, which affect the adsorption process were optimized. Maximum cadmium(II) removal from the aqueous solution was found at pH 9 with 0.3g/30mL adsorbent dose. The equilibrium in adsorption was attained after about 90 min of contact. Different adsorption isotherm models namely Langmuir, Freundlich and Temkin adsorption isotherm models were fitted to explain the equilibrium data obtained for the adsorption system. Temkin isotherm was found to show stronger correlation for cadmium(II) adsorption from the experimental solution onto the prepared adsorbent surface. INTRODUCTION Cadmium(II) is one of the major toxic heavy metals found to cause renal disorder, kidney damage, bone fraction, red blood cells destruction and high blood pressure[1]. The main pathway of Cd(II) contamination into the water streams is different industrial processes including mainly electroplating, metallurgical processes, manufacturing of plastics, pigment industries and Cd/Ni batteries[2]. Some conventional process namely chemical oxidation-reduction, adsorption, precipitation, reverse osmosis and electrolytic removal are extensively used to dispel or sequester cadmium from contaminated water[3]. Heavy metal adsorption onto the activated carbon surface has been practiced worldwide. But for developing countries it is difficult to use commercial activated carbon in massive scale because of its high price[4]. Many studies have been conducted with an aim to develop a low-cost activated carbon mainly from different agricultural byproducts, such as bagasse and rice husk[5], corn cob[6], nutshells[7], wood sawdust[8], jackfruit peel[9], rice husks[10], etc. In the present work, the extent of Cd 2+ adsorption from aqueous solution was studied using activated carbon as adsorbent prepared from Bombax ceiba fruit shell. Bombax ceiba is a tropical tree, which is usually known as Shimul in Bangladesh. Its fruit is one of the best sources of cotton while the shell is generated as a byproduct, which has no significant use and economical value. Under this study, the *Corresponding author: hosnaara1@gmail.com (M. H. Ara) DOI: 10.22034/jchr.2020.1903764.1154