Drinking Water Engineering and Science Discussions www.drink-water-eng-sci-discuss.net 1996-9473 1996-9481 1 1 2008 10.5194/dwesd-1-21-2008 http://www.drink-water-eng-sci-discuss.net/1/21/2008/ http://www.drink-water-eng-sci-discuss.net/1/21/2008/dwesd-1-21-2008.html http://www.drink-water-eng-sci-discuss.net/1/21/2008/dwesd-1-21-2008.pdf 21 44 2008-01-08 Prediction of RO/NF membrane rejections of PhACs and organic compounds: a statistical analysis V. Yangali-Quintanilla v.yangaliquintanilla@unesco-ihe.org T.-U. Kim M. Kennedy G. Amy UNESCO-IHE Institute for Water Education, Westvest 7, 2611 AX Delft, The Netherlands Delft University of Technology, Stevinweg 1, Delft, The Netherlands Pennsylvania State University at Harrisburg, Middletown, PA 17057, USA Rejections of pharmaceutical compounds (Ibuprofen, Diclofenac, Clofibric acid, Naproxen, Primidone, Phenacetin) and organic compounds (Dichloroacetic acid, Trichloroacetic acid, Chloroform, Bromoform, Trichloroethene, Perchloroethene, Carbontetrachloride, Carbontetrabromide) by NF (Filmtec, Saehan) and RO (Filmtec, Saehan, Toray, Koch) membranes were studied. Chloroform presented the lowest rejection due to small molar volume, equivalent width and length. Diclofenac and Primidone showed high rejections related to high molar volume and length. Dichloroacetic acid and Trichloroacetic acid presented good rejections caused by charge exclusion instead of steric hindrance mechanism influencing rejection. Bromoform and Trichloroethene showed low rejections due to small length and equivalent width. Carbontetrabromide, Perchloroethene and Carbontetrachloride with higher equivalent width than BF and TCE presented better rejections. A qualitative analysis of variables using Principal Component Analysis was successfully implemented for reduction of physical-chemical compound properties that influence membrane rejection of PhACs and organic compounds. Properties such as dipole moment, molar volume, hydrophobicity/hydrophilicity, molecular length and equivalent width were found to be important descriptors for prediction of membrane rejection. Ionic and neutral compounds were successfully separated before analysis. For membranes used in the experiments, we may conclude that charge repulsion was an important mechanism of rejection for ionic compounds. Molecular weight was a poor variable for rejection prediction. Membrane rejection of neutral compounds was well predicted by dipole moment, molar volume, length, equivalent width and hydrophobicity/hydrophilicity of compounds after analysis with Multiple Linear Regression. Adams, C., Wang, Y., Loftin, K., and Meyer, M.: Removal of Antibiotics form Surface Water and Distilled Water in Conventional Water Treatment Processes, J. Env. Eng., 128, 253–259, 2002. Childress, A. E. and Elimelech, M.: Relating nanofiltration membrane performance to membrane charge (electrokinetic) characteristics, Environ. Sci. Technol., 34, 3710–3716, 2000. Cho, J., Amy, G., and Pellegrino, J.: Membrane filtration of natural organic matter: comparison of flux decline, NOM rejection, and foulants during filtration with three UF membranes, Desalination, 127, 283–298, 2000. Heberer, T.: Occurrence, fate, and removal of pharmaceutical residues in the aquatic environment: a review of recent research data, Toxicol. Lett., 131, 5–17, 2002. Hirsch, R., Ternes, T., Haberer, K., and Kratz, K.-L.: Occurrence of antibiotics in the aquatic environment, Sci. Total Environ., 225, 109–118, 1999. Kim, T.-U., Amy, G., and Drewes, J.: Rejection of trace organic compounds by high-pressure membranes, Water Sci. Technol., 51, 335–344, 2005. Kimura, K., Amy, G., Drewes, J., and Watanabe, Y.: Adsorption of hydrophobic compounds onto NF/RO membranes: an artifact leading to overestimation of rejection, J. Mem. Sci. 221, 89–101, 2003. Kimura, K., Toshima, S., Amy, G., and Watanabe, Y.: Rejection of neutral endocrine disrupting compounds (EDCs) and pharmaceutical active compounds (PhACs) by RO membranes, J. Mem. Sci. 245, 71-78, 2004. Kiso, Y., Kon, T., Kitao, T., and Nishimura, K.: Rejection properties of alkyl phthalates with nanofiltration membranes, J. Mem. Sci. 182, 205–214, 2001a. Kiso, Y., Sugiura, T., Kitao, T., and Nishimura, K.: Effects of hydrophobicity and molecular size on rejection of aromatic pesticides with nanofiltration membranes, J. Mem. Sci. 192, 1-10, 2001b. Kiso, Y., Mizuno, A., Othman, R., Jung, Y. J., Kumano, A., and Ariji, A.: Rejection properties of pesticides with a hollow fiber NF membrane (HNF-1), Desalination, 143, 147–157, 2002. Kolpin, D. W., Furlong, E. T., Meyer, M. T., Thurman, E. M., Zaugg, S. D., Barber, L. B., and Buxton, H. T.: Pharmaceuticals, Hormones, and other organic wastewater contaminants in U.S. Streams, 1999–2000: A National Reconnaissance, Environ. Sci. Technol., 36, 1202–1211, 2002. Landau, S. and Everitt, B.: A Handbook of Statistical Analysis using SPSS, 2004, Chapman & Hall/CRC Press, 2004. Lyman, W. J., Reehl, W. F., and Rosenblatt, D. H.: Handbook of chemical property estimation methods, American Chemical Society, McGraw-Hill Inc., 17.1–17.25, 1990. Nghiem, L. D., Schäfer, A. I., and Elimelech, M.: Removal of natural hormones by nanofiltration membranes: measurement, modelling, and mechanisms, Environ. Sci. Technol., 38, 1888–-1896, 2004. Ozaki, H. and Li, H.: Rejection of organic compounds by ultra-low pressure reverse osmosis membrane, Water Res., 36, 123–130, 2002. Schaep, J. and Vandecasteele, C.: Evaluating the charge of nanofiltration membranes, J. Mem. Sci., 188, 129–136, 2001. Schäfer, A. I., Nghiem, L. D., and Waite, T. D.: Removal of the natural hormone estrone from aqueous solutions using nanofiltration and reverse osmosis, Environ. Sci. Technol., 37, 182–188, 2003. Ternes, T. A.: Occurrence of drugs in Germany sewage treatment plants and rivers, Water Res., 32, 3245–3260, 1998. Van der Bruggen, B., Schaep, J., Wilms, D., and Vandecasteele, C.: Influence of molecular size, polarity and charge on the retention of organic molecules by nanofiltration, J. Mem. Sci., 156, 29–41, 1999. Van der Bruggen, B., Schaep, J., Wilms, D., and Vandecasteele, C.: A comparison of models to describe the maximal retention of organic molecules in nanofiltration, Separ. Sci. Technol., 35, 169–182, 2000. Vieno, N., Tuhkanen, T., and Kronberg, L.: Removal of Pharmaceuticals in Drinking Water Treatment: Effect of Chemical Coagulation, Env. Tech., 27, 183–192, 2006.