IOSR Journal of Engineering (IOSRJEN) www.iosrjen.org ISSN (e): 2250-3021, ISSN (p): 2278-8719 Vol. 04, Issue 01 (January. 2014), ||V2|| PP 16-25 International organization of Scientific Research 16 | P a g e Biosorptionof Cadmium Ions ontoGarden Grass Abbas H. Sulaymon a , Ahmed A. Mohammed b , Tariq J. Al-Musawi c a Energy Eng. Dept., Baghdad University, Baghdad, Iraq b Environmental Eng. Dept., Baghdad University, Baghdad, Iraq c Corresponding author. Environmental. Eng. Dept., Baghdad University, Iraq. Abstract: -The garden grass was utilized as low cost adsorbent to remove cadmium ions from aqueous solution usingbiosorption. All the experiments were conducted in batch system to investigate the biosorption capacity as well as the effects of pH, temperature, agitation speed, and initial metal concentration on the biosorption efficacy. Fourier Transformation Infrared Spectroscopy analysis was used to find the effectsof functional groups of garden grass in biosorptionprocess. The results showed that the garden grass could be used efficiently to remove cadmium from aqueous solution and up to 85% of cadmium removal was obtainedat the optimal conditions. The biosorption equilibrium was reached at 60 min and the maximum biosorption capacity was found to be 17.2 mg/g for 1 g dose.Experimental isotherms data well fittedthe Langmuir model. Experimental kinetics data showed that the biosorption process fitted well the pseudo-second-order kinetics model. Keywords: - Garden grass,Cadmium,Biosorption, Equilibrium,Kinetics I. INTRODUCTION Nowadays, the pollution of environment by heavy metals has become one of the most serious environmental problems (Taha, et al. 2001). This is because they are highly toxic, non-biodegradable, and tend to accumulate causing different health problems in living organisms(Anayurt et al. 2009). The heavy metals enter in tissues through the food chain and accumulate in the body of all living organisms ( Doke et al. 2012). Therefore, the elimination of these metals from water and wastewater is important to protect public health. Normally water treatment is not practiced by the industries and as a consequence, many times heavy metals are found in aquatic environment well above the permissible limit. According to World Health Organization, the heavy metals of concern are cadmium, chromium, zinc, copper, lead, mercury, etc. (WHO 1984). Cadmium is an extremely toxic metal to humans, plants and animals.The major sources of cadmium into the waste streams are electroplating, use of phosphatic fertilizers, smelting, alloy manufacturing, pigments, plastics, batteries and mining (Tsezos 2001; Peavy et al. 1985). Kidney and bone damage have been described to the main problems for patient chronically exposed to cadmium(Barbier et al. 2005). In the present work, cadmium has been chosen as the contaminant in aqueous medium. There are several methods for the treatment of metal effluents such as precipitation, ion exchange, membrane processes, adsorption and biosorption. Biosorption has been defined as the property of certain biomolecules to bind and concentrate selected ions or other molecules from aqueous solution. As opposed to a much more complex phenomenon of bioaccumulation based on active metabolic transport, biosorption by dead biomass is passive and based mainly on the affinity between the biosorbent and sorbate (Volesky,2007; Diniz et al. 2008).Biosorbent comes under the following categories: bacteria, fungi, algae, industrial wastes and agricultural wastes (Hossain et al. 2012). Among them, agricultural wastes are the potential sources for producing biosorbents as they have low cost and no prominent utilization. A low cost biosorbents are defined as one which is abundant in nature, or is by-product or waste material from another industry. Several studies showed that agricultural waste either in natural or modified is highly efficient for the removal of pollutants. This can be attributed that agricultural wastes are composed of manyeffective functional groups such as lignin, cellulose, alcohols, aldehydes, ketonez, carboxylic, phenolic and ether groups (Lü et al. 2010). In case of removal of cation metals such Cd(II), Pb(II), and Cu(II), these groups have the ability to some extent to bind heavy metals by donation of an electron pair from these groups to form complexes with the metal ions in solution. Otherwise, the mechanism of sorption process of organic materials has been reported to be very complex and possibility involves the combination of diffusion, chelation, complxation, coordination, or microprecipitation mechanisms depending on the specific biosorbent (Veglio and Beolchini1997). Grass is an environmentally friendly, low cost, and abundant material after mowing gardens, lawns, and parks. Approximately, ten tons of grass is mower monthly from the gardens of Baghdad University. Often, these quantities were dumped in a municipal solid waste landfill. Few researches were carried out on the use of gardens grass (GG) as biosorbent. Hossain et al. (2012)were the first researchers whose use GG as biosorbent material. They have reported that the GGexhibits