1. Influences of environmental factors on the instant removal of Geosmin and 2-MIB by powdered activated carbon Viet Ly Quang a · Sung Kyu Maeng b · Ilhwan Choi c · Jin Hur a, * a Department of Environmental and Energy, Sejong University, Seoul 143-747, South Korea b Department of Civil and Environmental Engineering, Sejong University, Seoul 143-747, South Korea c Water Analysis and Research Center, K-water, 560 Sintanjin-ro, Daedeok-gu, Daejeon 307-711, South Korea Geosmin (GSM) and 2-methylisoborneol (2-MIB), two major earthy-musty taste and odor (T&O) compounds in natural surface water, are widely accepted to be non-toxic to human health, their presence even at very low concentration can cause consumer’s complaint, thus reducing confidence in water treatment systems (Srinivasan and Sorial 2011). Powdered activated carbon (PAC) technology has been demonstrated to successfully remove T&O compounds even though there are limitations such as the cost, competitive adsorption by the presence of natural organic matter (Matsui et al. 2012). In this study, the removal rates of semi-volatile T&O compounds by PAC were determined, and the influences of several environmental parameters such as pH, temperature, and turbidity on PAC dosages were examined. Introduction Sejong University Water was collected from in Gwangju, Kyungki province (South Korea). Experiments were conducted in jar tests with PAC dosage 0-200 mg/L, at pH 7 and 10, at the temperatures of 10, 20 and 30 o C and with turbidity of 0, 1000, 2000 NTU. The initial concentrations of 1000 ng/L and 2000 ng/L for 2-MIB and GSM, respectively. After contact time of 3 min, the samples containing T&O compounds were filtered through 0.2 µm membrane (cellulose acetate, advec, Japan), subsequently collected into amber vials without headspace. The samples were then transported to K-Water laboratory for analyzing by solid phase microextraction (SPME) gas chromatography -mass spectroscopy (GC-MS) (6040D, Standard Method 2005). Materials & Methods Temperature and pH showed insignificant influence on the removal rates of GSM and 2- MIB, while turbidity substantially enhanced the treatment efficiency, probably owing to the adsorptive interactions between kaolin and micropollutants. The model curve showed good fitting with the data. PAC is an effective method to remove persistent T&O compounds. A higher removal rate was observed for GSM than for 2-MIB, probably because of the lower solubility, molecular weight, and the flatter structure. Conclusions Matsui, Y., T. Yoshida, S. Nakao, D. R. U. Knappe and T. Matsushita (2012). "Characteristics of competitive adsorption between 2-methylisoborneol and natural organic matter on superfine and conventionally sized powdered activated carbons." Water Research 46(15): 4741-4749. Srinivasan, R. and G. A. Sorial (2011). "Treatment of taste and odor causing compounds 2- methyl isoborneol and geosmin in drinking water: A critical review." Journal of Environmental Sciences 23(1): 1-13. References Results & Discussion This work was supported by Korea Environmental Industry and Technology Institute (No. 2014001800002 Acknowledgements Figure 3. Effects of temperature, pH and turbidity on removal rates of T&O compounds Figure 1. Representative of SPME scheme used for GSM and 2-MIB analysis (www.Scinco.com) Table 1. Fitting curve y = a*(1-e -bx ) for predicting removal rate of T&O compounds MIBGSM abR2R2 abR2R2 Temp. 1091.170.0090.883112.820.0080.963 2093.170.0080.962117.190.0070.958 3080.340.0120.905100.430.0120.965 pH 793.040.0080.962117.150.0080.958 1092.690.0110.987106.970.010.992 NTU 088.330.0090.97798.620.0090.944 100093.040.0080.962117.140.0080.972 200087.930.0180.99996.610.0190.999 DOM research Lab. Figure 2. Mass spectra of A) Geosmin and B) 2-MIB.