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oai:www.ideals.illinois.edu:2142/31985 2023-07-10 col_2142_14770 col_2142_5131 com_2142_3518 com_2142_234 com_2142_5130

Mariñas, Benito J. Renkens, Tennie 2012-06-27T21:23:10Z 2014-06-28T10:00:24Z 2012-05 2012-06-27T21:23:10Z 2012-05 Changes in the structure of the SW30HR RO membrane exposed to seawater, phosphate buffer, and standard seawater disinfected with monochloramine (NH2Cl) are investigated. Three types of experiments were performed: (1) exposure of RO membrane (active and support layers) to monochloramine (2, 20 and 200 mg/L as Cl2) and target proportional levels of iodide (0.06, 0.6 and 6 mg/L) or bromide (60, 600 and 6,000 mg/L) at constant exposure CT=384 mg×h/L; (2) exposure of support layer only to monochloramine at CT values of 1,000 and 30,000 mg×h/L at a monochloramine concentration of 200 mg/L as Cl2; (3) exposure of RO membrane (active and support layers) to monochloramine at CT values of 1,000, 5,000 and 30,000 mg×h/L at a monochloramine concentration of 200 mg/L as Cl2 in the presence of only 6 mg/L of iodide, only 6,000 mg/L of bromide, and both 6 mg/L of iodide and 6,000 mg/L of bromide. Results revealed that monochloramine may be reacting with the polysulfone support of RO membranes. RBS analyses have revealed that the RO membrane support might undergo damage. Recent work involves determining the effect of active layer-bound halogens on carboxylic group accessibility. Cesium (Cs+), silver (Ag+), and barium (Ba2+) were used as ion probes to quantify the changes associated with membranes exposed to three different batch reactor conditions (1) seawater with 2 ppm NH2Cl; (2) phosphate buffer with 2 ppm NH2Cl and 65 mg/L KBr as Br-; (3) standard seawater with 2 ppm NH2Cl and 65 mg/L KBr as Br-. Preliminary results indicate a shift in the pKa values of active layer carboxylic groups in batch reactors containing NH2Cl in comparison to control reactors. Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2012-04-12T20:59:11Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 2 Renkens_Tennie.docx: 12572397 bytes, checksum: c8f0b3fcfbe8587bc5a73950396dfe9e (MD5) Renkens_Tennie.pdf: 6861436 bytes, checksum: efc6bb8c7d25f6536e59bec6db018962 (MD5) Made available in DSpace on 2012-06-27T21:23:10Z (GMT). No. of bitstreams: 3 Renkens_Tennie.pdf: 6861315 bytes, checksum: feef832e1e84aab034829c27af12b9c0 (MD5) license.txt: 4064 bytes, checksum: d310d222397bb957872ae799c9e7afa5 (MD5) Renkens_Tennie.docx: 12572753 bytes, checksum: 2b16133ed18077e973a9e9eaf4e212c8 (MD5) Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by William Ingram (wingram2@illinois.edu) on 2012-06-27T21:24:45Z Item is restricted until 2014-06-27T21:24:27Z Item reinstated by Sarah Shreeves (sshreeve@illinois.edu) on 2014-06-28T10:00:24Z Item was in collections: Dissertations and Theses - Civil and Environmental Engineering (ID: 672) Graduate Theses and Dissertations at Illinois (ID: 204) No. of bitstreams: 3 Renkens_Tennie.pdf: 6861315 bytes, checksum: feef832e1e84aab034829c27af12b9c0 (MD5) license.txt: 4064 bytes, checksum: d310d222397bb957872ae799c9e7afa5 (MD5) Renkens_Tennie.docx: 12572753 bytes, checksum: 2b16133ed18077e973a9e9eaf4e212c8 (MD5) Item released from any restrictions by Sarah Shreeves (sshreeve@illinois.edu) on 2014-06-28T10:00:24Z http://hdl.handle.net/2142/31985 en Copyright 2012 Tennie Renkens reverse osmosis membrane fouling halogenation Changes in the structure of SW30HR RO membrane exposed to chloraminated seawater and synthetic solutions text Civil & Environmental Eng 1251 Environ Engr in Civil Engr 0231 University of Illinois at Urbana-Champaign Thesis M.S. MS:Env Engr Civil Engr -UIUC 10KS0231MS