砷（As）是一种类金属，以多种形式（有机和无机）、氧化状态和价态天然存在于饮用水中。无机砷主要存在于饮用水中，以砷酸盐（as（V））和亚砷酸盐（as（III））的形式存在。在典型的pH条件下（6.3-9.3），As（V）以二价阴离子形式存在，而As（III）则完全质子化，以不带电分子形式存在。可通过向含有As（III）的溶液中添加化学氧化剂（例如氯）或将含有As（III）的溶液暴露于紫外光下，在液相中将As（III）氧化为As（V）。或者，可以使用固相氧化剂。 本研究的具体目标是:研究氯、高锰酸盐、臭氧、二氧化氯、一氯胺、固相氧化介质和254 nm紫外线辐射对As（III）氧化为As（V）的有效性；测定pH值在6.3-8.3范围内对As（III）氧化为As（V）的影响；测定干扰还原剂（如溶解铁、溶解锰、硫化物和总有机碳）的影响，以及低温（5摄氏度）对氧化过程的影响。包括表格、数字。

Arsenic (As) is a metalloid that is naturally present in drinkingwater in a variety of forms (organic and inorganic), oxidation states, and valences. Inorganic arsenic predominates in drinking water and is present as arsenate (As(V)) and arsenite (As(III)). Under typical pH conditions (6.3-9.3), As(V) exists asa divalent anion while As(III) is fully protonated and exists as an uncharged molecule. Oxidation of As(III) to As(V) may be performed in the liquid phase via the addition of chemical oxidants such as chlorine to a solution containing As(III) or by exposing the As(III)-containing solution to ultraviolet light. Alternatively, a solid-phase oxidant may be used. The specific objectives of this study were to: study the effectiveness of chlorine, permanganate, ozone, chlorine dioxide, monochloramine, solid-phase oxidizing media, and ultraviolet radiation at 254 nm, for the oxidation of As(III) to As(V); determine the effect of pH, in the range 6.3-8.3, on the oxidation of As(III) to As(V); and, determine the effect of interfering reductants such as dissolved iron, dissolved manganese, sulfide, and total organic carbon, and the effect of lowtemperature (5 degrees C) on the oxidation process. Includes tables, figures.