{"id":{"repo_id":"gatech","oai_identifier":"oai:repository.gatech.edu:1853/54402"},"canonical_url":"https://search.dev.ndltd.org/etd/gatech/oai:repository.gatech.edu:1853/54402","repository":{"repo_id":"gatech","name":"Georgia Tech","base_url":"https://repository.gatech.edu/server/oai/request"},"display":{"title":"Effect of combined UV and free chlorine on the formation of chloronitromethanes","abstract":"The results from this study show how different precursors affect halonitromethane (HNM) formation as well as how different free chlorine doses can affect HNM speciation. This study shows that the low pressure ultraviolet (LPUV) and free chlorine concurrent exposure can enhance HNM formation. In addition, most previous studies in the literature showed trichloronitromethane (TCNM) forming in greater quantities followed by monochloronitromethane (MCNM) and dichloronitromethane (DCNM). However, the results of this study show that, in deionized (DI) water matrices, MCNM forms in greater quantities at chlorine to nitrogen (Cl:N) ratios less than 3, while TCNM forms in greater quantities at Cl:N ratios greater than 3. Even so, the increase in TCNM formation did not increase linearly as the Cl:N ratio increased; there was a decreased rate of return when Cl:N ratios were greater than 3. The type of nitrogenous precursors can affect the amount of HNMs formed, with glycine forming a higher amount of total HNMs compared to methylamine (MA) and dimethylamine (DMA). The source of water can also affect which HNM species is formed in greater concentrations. The limited number of real water samples showed that the river waters have higher than normal total organic carbon (TOC) and dissolved organic nitrogen (DON), which are associated with greater nitrogenous precursors and higher HNM formation. Each water source can have different nitrogenous precursors; river waters may have more algal organic matter while wastewater would have higher organic matter and synthetic chemicals. In addition, source waters can have different constituents, such as varying dissolved oxygen (DO) levels and inorganic ions, which might inhibit HNM formation or affect specification.","abstract_html":"The results from this study show how different precursors affect halonitromethane (HNM) formation as well as how different free chlorine doses can affect HNM speciation. This study shows that the low pressure ultraviolet (LPUV) and free chlorine concurrent exposure can enhance HNM formation. In addition, most previous studies in the literature showed trichloronitromethane (TCNM) forming in greater quantities followed by monochloronitromethane (MCNM) and dichloronitromethane (DCNM). However, the results of this study show that, in deionized (DI) water matrices, MCNM forms in greater quantities at chlorine to nitrogen (Cl:N) ratios less than 3, while TCNM forms in greater quantities at Cl:N ratios greater than 3. Even so, the increase in TCNM formation did not increase linearly as the Cl:N ratio increased; there was a decreased rate of return when Cl:N ratios were greater than 3. The type of nitrogenous precursors can affect the amount of HNMs formed, with glycine forming a higher amount of total HNMs compared to methylamine (MA) and dimethylamine (DMA). The source of water can also affect which HNM species is formed in greater concentrations. The limited number of real water samples showed that the river waters have higher than normal total organic carbon (TOC) and dissolved organic nitrogen (DON), which are associated with greater nitrogenous precursors and higher HNM formation. Each water source can have different nitrogenous precursors; river waters may have more algal organic matter while wastewater would have higher organic matter and synthetic chemicals. In addition, source waters can have different constituents, such as varying dissolved oxygen (DO) levels and inorganic ions, which might inhibit HNM formation or affect specification.","abstract_has_math":false,"creators":["Vargas, David"],"institution":"Georgia Institute of Technology","degree_name":null,"degree_level":"Masters","degree_discipline":null,"degree_department":"Civil and Environmental Engineering","school":null,"contributors":[],"advisors":["Huang, Ching-Hua"],"committee_chairs":[],"committee_members":["Pavlostathis, Spyros","Chen, Yongsheng"],"year":2015,"date_issued":"2015-11-23","date_published":"2015-11-23","updated_at":"2026-07-27T19:50:08Z","subjects":["Halonitromethane","Disinfection byproduct","Ultraviolet","Free chlorine","Cholronitromethane"],"languages":["en_US"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/1853/54402","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Huang, Ching-Hua"]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Pavlostathis, Spyros","Chen, Yongsheng"]},{"key":"dc:contributor.department","label":"Department","values":["Civil and Environmental Engineering"]},{"key":"dc:creator","label":"Author","values":["Vargas, David"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2016-01-07T17:35:57Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2016-01-07T17:35:57Z"]},{"key":"dc:date.issued","label":"Date","values":["2015-11-23"]},{"key":"dc:publisher","label":"Institution","values":["Georgia Institute of Technology"]},{"key":"dc:type","label":"Dc Type","values":["Text"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Halonitromethane","Disinfection byproduct","Ultraviolet","Free chlorine","Cholronitromethane"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en_US"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/1853/54402"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["The results from this study show how different precursors affect halonitromethane (HNM) formation as well as how different free chlorine doses can affect HNM speciation. This study shows that the low pressure ultraviolet (LPUV) and free chlorine concurrent exposure can enhance HNM formation. In addition, most previous studies in the literature showed trichloronitromethane (TCNM) forming in greater quantities followed by monochloronitromethane (MCNM) and dichloronitromethane (DCNM). However, the results of this study show that, in deionized (DI) water matrices, MCNM forms in greater quantities at chlorine to nitrogen (Cl:N) ratios less than 3, while TCNM forms in greater quantities at Cl:N ratios greater than 3. Even so, the increase in TCNM formation did not increase linearly as the Cl:N ratio increased; there was a decreased rate of return when Cl:N ratios were greater than 3. The type of nitrogenous precursors can affect the amount of HNMs formed, with glycine forming a higher amount of total HNMs compared to methylamine (MA) and dimethylamine (DMA). The source of water can also affect which HNM species is formed in greater concentrations. The limited number of real water samples showed that the river waters have higher than normal total organic carbon (TOC) and dissolved organic nitrogen (DON), which are associated with greater nitrogenous precursors and higher HNM formation. Each water source can have different nitrogenous precursors; river waters may have more algal organic matter while wastewater would have higher organic matter and synthetic chemicals. In addition, source waters can have different constituents, such as varying dissolved oxygen (DO) levels and inorganic ions, which might inhibit HNM formation or affect specification."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["M.S."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Effect of combined UV and free chlorine on the formation of chloronitromethanes"]}]}],"canonical_facts":{"dc:contributor.advisor":["Huang, Ching-Hua"],"dc:contributor.committeemember":["Pavlostathis, Spyros","Chen, Yongsheng"],"dc:contributor.department":["Civil and Environmental Engineering"],"dc:creator":["Vargas, David"],"dc:date.accessioned":["2016-01-07T17:35:57Z"],"dc:date.available":["2016-01-07T17:35:57Z"],"dc:date.issued":["2015-11-23"],"dc:description.abstract":["The results from this study show how different precursors affect halonitromethane (HNM) formation as well as how different free chlorine doses can affect HNM speciation. This study shows that the low pressure ultraviolet (LPUV) and free chlorine concurrent exposure can enhance HNM formation. In addition, most previous studies in the literature showed trichloronitromethane (TCNM) forming in greater quantities followed by monochloronitromethane (MCNM) and dichloronitromethane (DCNM). However, the results of this study show that, in deionized (DI) water matrices, MCNM forms in greater quantities at chlorine to nitrogen (Cl:N) ratios less than 3, while TCNM forms in greater quantities at Cl:N ratios greater than 3. Even so, the increase in TCNM formation did not increase linearly as the Cl:N ratio increased; there was a decreased rate of return when Cl:N ratios were greater than 3. The type of nitrogenous precursors can affect the amount of HNMs formed, with glycine forming a higher amount of total HNMs compared to methylamine (MA) and dimethylamine (DMA). The source of water can also affect which HNM species is formed in greater concentrations. The limited number of real water samples showed that the river waters have higher than normal total organic carbon (TOC) and dissolved organic nitrogen (DON), which are associated with greater nitrogenous precursors and higher HNM formation. Each water source can have different nitrogenous precursors; river waters may have more algal organic matter while wastewater would have higher organic matter and synthetic chemicals. In addition, source waters can have different constituents, such as varying dissolved oxygen (DO) levels and inorganic ions, which might inhibit HNM formation or affect specification."],"dc:description.degree":["M.S."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["http://hdl.handle.net/1853/54402"],"dc:language.iso":["en_US"],"dc:publisher":["Georgia Institute of Technology"],"dc:subject":["Halonitromethane","Disinfection byproduct","Ultraviolet","Free chlorine","Cholronitromethane"],"dc:title":["Effect of combined UV and free chlorine on the formation of chloronitromethanes"],"dc:type":["Text"],"thesis:degree_level":["Masters"]},"updated_at":"2026-07-27T19:50:08Z"}