Green catalytic process for in situ oxidation of Arsenic(III) in concentrated streams using activated carbon and oxygen gas

Behavior of Oxidative Precipitation of High-Arsenic (III) Solution Utilizing Activated Carbon with Air Injection

“…In addition, the greater the amount of AC added, the better was the reaction efficiency, removing 93-94% of As with more than 5 w/v% of AC addition. Finally, X-ray diffraction analysis confirmed that the precipitate formed from the oxidative reaction was scorodite (FeAsO 4) .…”

“…그 외에 orpiment (As 2 S 3 ), realgar (AsS) 등 의 비소 함유 황화광물이 대표적이며, 이들 광물은 대개 구 리, 금, 은 등의 유가금속과 함께 발견된다 2,3) . 따라서 비소 는 이들 유가금속의 제련 공정을 통해 이동성(mobility)이 생기며, 또는 자연계에 존재하는 미생물의 활동으로 인해 수계로 용출되어 나오기도 한다 [3][4][5] . 비소가 용출된 경우, 일반적으로 3가 비소가 5가 비소에 비해 약 60배 정도 독 성이 강한 것으로 알려져 있는데, 이는 3가 비소가 5가 비 소에 비해 생명체 내에 보다 더 잘 흡수되기 때문이다 6,7) .…”

Redox-induced transformation of potentially toxic elements with organic carbon in soil

“…Although the inherent electron-accepting capacity of organic carbon is relatively low, it can support the ROS formation as a rich electron pool for the oxidation of several PTEs with the addition of oxidizing agent. For instance, oxidants, such as persulfate or O 2 , could be activated by electrons from organic carbon, leading to the oxidation of pollutants (Wu et al 2020;Zhou et al 2021). For example, the oxidation of As(III) to As(V) leads to lower toxicity and mobility, which are critical for As immobilization in soil.…”

Insights into the Adsorption and Photocatalytic Oxidation Behaviors of Boron-Doped TiO2/g-C3N4 Nanocomposites toward As(III) in Aqueous Solution

“…13,15−18 Compared with the traditional absorption process, the coupling process can further convert As(III) to As(V) and enhance the adsorption of total As. 19,20 Moreover, without using oxidizing reagents, the coupled photocatalytic oxidation−adsorption process exhibits more advantages, such as a clean process, sustainability, and the absence of secondary pollution. 21−23 At present, TiO 2 has become one of the most studied and promising materials due to its low cost, abundant raw materials, high photocatalytic activity, good chemical stability, and nontoxicity.…”

“…The coupled oxidation–adsorption process, such as chemical or catalytic oxidation–adsorption coupling process, has drawn considerable attention in recent years, since it provides an alternative scenario to As­(III) removal. ,− Compared with the traditional absorption process, the coupling process can further convert As­(III) to As­(V) and enhance the adsorption of total As. , Moreover, without using oxidizing reagents, the coupled photocatalytic oxidation–adsorption process exhibits more advantages, such as a clean process, sustainability, and the absence of secondary pollution. − At present, TiO 2 has become one of the most studied and promising materials due to its low cost, abundant raw materials, high photocatalytic activity, good chemical stability, and nontoxicity. , However, the wide band gap (3.2 eV) of TiO 2 limits its absorption of solar radiation in the UV light range, which accounts for about 4–6% of the solar spectrum . Moreover, the rapid recombination of photogenerated electrons and holes drastically reduces the efficiency of the photocatalytic process .…”