Department of Civil, Environmental and Architectural Engineering, University of Colorado, Boulder, Boulder, Colorado 80309, United States.
Environ Sci Technol. 2012 Apr 3;46(7):3788-94. doi: 10.1021/es2043454. Epub 2012 Mar 22.
The photochemical formation of hydroxyl radical (HO•) from effluent organic matter (EfOM) was evaluated using three bulk wastewater samples collected at different treatment facilities under simulated sunlight. For the samples studied, the formation rates of HO•(R(HO•)) were obtained from the formation rate of phenol following the hydroxylation of benzene. The values of R(HO•) ranged from 2.3 to 3.8 × 10(-10) M s(-1) for the samples studied. The formation rate of HO• from nitrate photolysis (R(NO3)(HO•)) was determined to be 3.0 × 10(-7) M(HO)• M(NO3)(-1) s(-1). The HO• production rate from EfOM (R(EfOM)(HO•)) ranged from 0.76 to 1.3 × 10(-10) M s(-1). For the wastewater samples studied, R(EfOM)(HO•) varied from 1.5 to 2.4 × 10(-7) M(HO)• M(C)(-1) (s-1) on molarcarbon basis, which was close to HO• production from nitrate photolysis. The apparent quantum yield for the formation of HO• from nitrate (Φ(NO3-HO•)(a)) was determined as 0.010 ± 0.001 for the wavelength range 290-400 nm in ultrapure water. The apparent quantum yield for HO• formation in EfOM (Φ(EfOM-HO•)(a)) ranged from 6.1 to 9.8 × 10(-5), compared to 2.99 to 4.56 × 10(-5) for organic matter (OM) isolates. The results indicate that wastewater effluents could produce significant concentrations of HO•, as shown by potential higher nitrate levels and relatively higher quantum yields of HO• formation from EfOM.
采用模拟阳光条件下收集的三个不同处理设施的废水样品，评估了污水有机物（EfOM）在光化学过程中形成羟基自由基（HO•）的情况。在所研究的样品中，HO•的形成速率（R（HO•））是通过苯的羟化生成苯酚的速率获得的。研究样品的 R（HO•）值范围为 2.3 到 3.8×10（-10）M s（-1）。通过测定硝酸盐光解（R（NO3）（HO•））的形成速率，确定 HO•的形成速率为 3.0×10（-7）M（HO）•M（NO3）（-1）s（-1）。EfOM 的 HO•生成速率（R（EfOM）（HO•））范围为 0.76 到 1.3×10（-10）M s（-1）。在所研究的废水样品中，R（EfOM）（HO•）在以摩尔碳为基础的条件下，从 1.5 到 2.4×10（-7）M（HO）•M（C）（-1）（s-1）不等，这与硝酸盐光解生成的 HO•相近。在超纯水的 290 到 400nm 波长范围内，硝酸盐形成 HO•的表观量子产率（Φ（NO3-HO•）（a））确定为 0.010±0.001。EfOM 中 HO•形成的表观量子产率（Φ（EfOM-HO•）（a））范围为 6.1 到 9.8×10（-5），而有机物（OM）分离物的范围为 2.99 到 4.56×10（-5）。结果表明，废水排放物可能会产生大量的 HO•，这表明硝酸盐水平较高，且 EfOM 生成 HO•的量子产率相对较高。
