ACIDIC METHANOL methylation for HAA ANALYSIS: LIMITATIONS AND POSSIBLE SOLUTIONS

• Published in: Journal - American Water Works Association Vol. 94; no. 11; pp. 115 - 122
• Main Authors: XIE, YUEFENG, RASHID, INNI, HAOJIANG ("JOE") ZHOU, GAMMIE, LESLIE
• Format: Journal Article
• Language: English
• Published: Denver, CO American Water Works Association 01.11.2002
• Subjects: Acids; Analysis; Applied sciences; By products; Chromatography; Disinfection & disinfectants; Disinfection Byproducts; Drinking water; Drinking water and swimming-pool water. Desalination; Edmonton, Alberta, Canada; Efficiency; Engineering; Environmental agencies; Environmental engineering; Environmental protection; Esters; Exact sciences and technology; Haloacetic Acids; Laboratories; Methods; Methylation; Pollution; Potable water; R&D; Research & development; Solvents; Studies; Sulfuric acids; Technology; Temperature; Waste byproducts; Water temperature; Water treatment; Water treatment and pollution; United States > US; Drinking water; Chemical analysis; Experimental study; Methylation; Halogen Organic compounds
• ISSN: 0003-150X; 1551-8833
• DOI: 10.1002/j.1551-8833.2002.tb10235.x

Acidic methanol methylation is a common derivatization process for haloacetic acid (HAA) analysis. The Pennsylvania State University at Harrisburg and EPCOR Water Services in Edmonton, Alta., conducted a study on acidic methanol methylation for HAAs. Using the current methylation conditions (US Environmental Protection Agency method 552.2), the authors observed incomplete methylation of HAAs, especially for trihaloacetic acids, which could significantly affect the accuracy of these HAA analytical results. The effects of methylation time, methylation temperature, volume of acidic methanol, and composition of acidic methanol on methylation efficiency were studied. This research suggests that acidic methanol methylation efficiency could be improved by increasing the volume of acidic methanol, methylation temperature, methylation time, or all three. The authors also investigated other common analytical problems associated with acidic methanol methylation. Additional studies are suggested to further optimize the acidic methanol methylation procedure for HAA analysis.