Chloral hydrate: Formation and removal by drinking water treatment

Research Article| September 01 2004 Chloral hydrate: Formation and removal by drinking water treatment Lisa Barrott Lisa Barrott 1MWH, 201 Amersham Road, High Wycombe, Buckinghamshire HP13 5AJ, UK E-mail: lisa.barrott@mwhglobal.com Search for other works by this author on: This Site PubMed Google Scholar Journal of Water Supply: Research and Technology-Aqua (2004) 53 (6): 381–390. https://doi.org/10.2166/aqua.2004.0030 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Cite Icon Cite Permissions Search Site Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll JournalsThis Journal Search Advanced Search Citation Lisa Barrott; Chloral hydrate: Formation and removal by drinking water treatment. Journal of Water Supply: Research and Technology-Aqua 1 September 2004; 53 (6): 381–390. doi: https://doi.org/10.2166/aqua.2004.0030 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Chloral hydrate (the hydrated form of trichloroacetaldehyde) is formed in water treatment as a by-product of the reaction between chlorine and naturally occurring organic material. Although a clear link between adverse health effects and levels of chloral hydrate in drinking water has not been established, the World Health Organisation (WHO) has set a Provisional Guideline Value of 10 µg l−1. This paper reviews the potential for the formation and removal of chloral hydrate in drinking water treatment processes.Two possible formation mechanisms for chloral hydrate are the reaction between amino acids and chlorine and the reaction between the aldehydes (formed when natural organic material is oxidised) and chlorine. Chloral hydrate can decay in alkaline conditions to give chloroform and in oxidising conditions to give trichloroacetic acid. Although the optimum conditions for the minimisation of trihalomethanes (THMs) may be different from the optimum conditions for the minimisation of chloral hydrate, the removal of organic precursors is common to both. Enhanced coagulation has the potential to reduce chloral hydrate levels in the treated water and to be the most efficient, convenient and cost effective method of reducing chloral hydrate levels in the treated water. Free chlorine is necessary for significant formation of chloral hydrate. chloral hydrate, chlorination, disinfection by-products, enhanced coagulation, water treatment This content is only available as a PDF. © IWA Publishing 2004 You do not currently have access to this content.