Leshuk Tim, Wong Timothy, Linley Stuart, Peru Kerry M, Headley John V, Gu Frank
Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada; Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
Department of Chemical Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
Chemosphere. 2016 Feb;144:1854-61. doi: 10.1016/j.chemosphere.2015.10.073. Epub 2015 Nov 11.
Bitumen mining in the Canadian oil sands creates large volumes of oil sands process-affected water (OSPW), the toxicity of which is due in part to naphthenic acids (NAs) and other acid extractable organics (AEO). The objective of this work was to evaluate the potential of solar photocatalysis over TiO2 to remove AEO from OSPW. One day of photocatalytic treatment under natural sunlight (25 MJ/m(2) over ∼14 h daylight) eradicated AEO from raw OSPW, and acute toxicity of the OSPW toward Vibrio fischeri was eliminated. Nearly complete mineralization of organic carbon was achieved within 1-7 day equivalents of sunlight exposure, and degradation was shown to proceed through a superoxide-mediated oxidation pathway. High resolution mass spectrometry (HRMS) analysis of oxidized intermediate compounds indicated preferential degradation of the heavier and more cyclic NAs (higher number of double bond equivalents), which are the most environmentally persistent fractions. The photocatalyst was shown to be recyclable for multiple uses, and thus solar photocatalysis may be a promising "green" advanced oxidation process (AOP) for OSPW treatment.
加拿大油砂中的沥青开采产生了大量油砂加工受影响水（OSPW），其毒性部分归因于环烷酸（NAs）和其他酸可萃取有机物（AEO）。这项工作的目的是评估TiO₂ 光催化作用从OSPW中去除AEO的潜力。在自然阳光下进行一天的光催化处理（在约14小时的日照时间内为25 MJ/m²）可从原始OSPW中去除AEO，并消除了OSPW对费氏弧菌的急性毒性。在相当于1 - 7天日照时间内实现了有机碳的近乎完全矿化，并且降解显示通过超氧化物介导的氧化途径进行。对氧化中间化合物的高分辨率质谱（HRMS）分析表明，较重且环数更多的NAs（双键当量数更高）优先降解，而这些是在环境中最持久的部分。该光催化剂可多次循环使用，因此太阳能光催化可能是一种用于处理OSPW的有前景的“绿色”高级氧化工艺（AOP）。
