12 th ISE 2018, Tokyo, Japan CHARACTERISTICS OF CADMIUM ADSORPTION ONTO GRANULATED CLAY BRICK AND LATERITE T.D.M HAI Graduate School of Science and Engineering, Saitama University, Saitama, Japan G.M.P KUMARA Graduate School of Science and Engineering, Saitama University, Saitama, Japan T.T.V NGA Faculty of Environmental Engineering, National University of Civil Engineering, Hanoi, Vietnam N.H GIANG Faculty of Civil Engineering, National University of Civil Engineering, Hanoi, Vietnam KEN KAWAMOTO Graduate School of Science and Engineering, Saitama University, Saitama, Japan There is an environmental concern that presence of cadmium in wastewater associates with carcinogenic effects. Additionally, construction and demolition waste is rapidly increasing in Vietnam due to the expansion of construction industry. Vietnam granulated clay brick (CB) and laterite block (LB) were used in this study to adsorb Cd2+ in wastewater by batch experiment. The result shows that the adsorption of CB and LB were captured well by Langmuir and Freundlich model respectively. 1. INTRODUCTION One of environmental issue in the world today is that heavy metal toxicity of Cadmium associates with carcinogenic effects. The occurrence of Cd 2+ in water resource primarily results from corrosion of galvanized and Cadmium-composing pipe lines, untreated effluent from battery manufacture, mining industry, production of phosphate fertilizer, and electronic components [1]. After Itai-Itai bone disease in Japan in 1960, which patients were exposed to Cd 2+ cause damage, there has been increasing attentions to the improper discharge of the heavy metal to the environment. The remediation of water contaminated by Cadmium has been developed in conventional ways of water treatment, including: chemical precipitation, ion exchange/ solvent extraction, coagulation/ flocculation and membrane filtration [2]. Due to limitations on cost of mentioned methods, there is a need to research alternatives to sustainably obtain reasonable water treatment technique [3]. As a result of rapid growth in construction industry, there are increasingly environmental concerns related to construction and demolition waste (CDW) in Vietnam. CDW is generated from phases of building construction, demolition activities, construction site clearing and excavation [4]. In terms of volume, CDW accounts for approximately 10-20 % of total solid waste. In 2015, 2.5 million tons of CDW generated in Vietnam with the main components such as brick and building blocks (31%), concrete (23%) [5]. The common methods of CDW treatment are landfill and dumping [6]. Despite the fact that CDW management has been researched in a wide range of nations such Australia and Japan, there is a lack of attention to the problem of CDW treatment in the case of Vietnam, particularly recycling [7]. Another outstanding point is that compared to geo- and biosorbents to deal with appearance of heavy metal in wastewater, CDW and recycled materials possess the same potential [3]. Therefore, the present study examines the utilization of clay brick (CB) and laterite block (LB) as low-cost adsorbents, the two major construction materials in Vietnam, to treat Cd 2+ in wastewater. 2. MATERIALS AND METHOD 2.1. Material selection and preparation Clay brick (CB) and laterite block (LB) used in this study were obtained from building material manufacturing factories in Bac Giang province and Hanoi city, Vietnam respectively. The materials then were ground and sieved to achieve two examined particle size fractions such as less than 0.105mm and 0.105 - 2 mm. Basic physical and chemical properties of selected materials in each fraction were tabulated in Table 1.