School of Chemical Engineering, Sichuan University, Chengdu, 610065, China.
Biodegradation. 2021 Aug;32(4):377-388. doi: 10.1007/s10532-021-09943-0. Epub 2021 Apr 10.
P-nitrophenol (PNP or 4-NP) has been widely used as a biorefractory raw material in chemical industry, whereas been highly concerned for its characteristics of mutagenic/carcinogenic activity and food chain bioaccumulation. In this study, an anaerobic semi-fixed bed biofilm reactor (An-SFB-BR) was constructed and used to treat PNP wastewater which discharged from chemical industries. Experimental results revealed that the An-SFB-BR was successfully cultivated with the gradually increasing of influent PNP from 0 to 540 mg/L (gradually increased 10 mg/L every time in stage II and 30-50 mg/L for stage III), with the observation of an average removal efficiency of 98% for PNP and 80% for chemical oxygen demand (COD), also a biogas production and biogas production rate of 2.1 L/(L·d) and 0.57 m/kg-COD, respectively. Finally, the conversion rate of P-aminophenol (PAP), the primary intermediate of PNP reached 80% after An-SFB-BR biodegradation. A relatively stable pH was maintained throughout the entire process, and insignificant VFA accumulation. The reactor exhibited a strong toxic shock resistance, and 16S rRNA sequencing results demonstrated that the dominant microbial community changed slightly with the gradually increasing of PNP concentration, which guaranteed the PNP removal efficiency.
对硝基苯酚（PNP 或 4-NP）作为一种具有遗传毒性/致癌性和食物链生物累积性的生物难降解工业原料，在化学工业中得到了广泛的应用。本研究构建了一种厌氧半固定床生物膜反应器（An-SFB-BR），用于处理来自化工行业的 PNP 废水。实验结果表明，An-SFB-BR 成功培养，进水 PNP 浓度逐渐从 0 增加到 540mg/L（在第二阶段每次逐渐增加 10mg/L，第三阶段为 30-50mg/L），平均 PNP 和化学需氧量（COD）去除率分别为 98%和 80%，沼气产量和沼气产率分别为 2.1L/（L·d）和 0.57m/kg-COD。最后，PNP 生物降解后，主要中间产物对氨基苯酚（PAP）的转化率达到 80%。整个过程中 pH 值相对稳定，VFA 积累不明显。该反应器表现出较强的抗毒性冲击能力，16S rRNA 测序结果表明，随着 PNP 浓度的逐渐增加，优势微生物群落变化不大，保证了 PNP 的去除效率。
