Patel Surabhi, Mondal Somen, Majumder Subrata Kumar, Das Papita, Ghosh Pallab
Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
Department of Chemical Engineering, Jadavpur University, Kolkata 700032, West Bengal, India.
ACS Omega. 2020 Dec 10;5(50):32305-32317. doi: 10.1021/acsomega.0c04139. eCollection 2020 Dec 22.
In the present study, a combined approach of ozone-based advanced oxidation and adsorption by activated char was employed for the treatment of a pharmaceutical industrial effluent. Ozone is a selective oxidant, but the addition of HO generated hydroxyl radicals, which is a non-selective stronger oxidant than ozone. The effluent obtained from the pharmaceutical industry mainly contained anti-cancer drugs, anti-psychotic drugs, and some pain killers. The peroxone process had 75-88.5% chemical oxygen demand (COD) reduction efficiency at pH 5-11 in 3 h. Adsorption by activated char further reduced the COD to 85.4-92.7% for pH 5-11 in 2.5 h. All other water quality parameters were significantly decreased (>73% removal) during ozonation. The primary operational parameters (system pH and HO concentration) were also varied, and their effects were analyzed. The pseudo-first-order rate constants for ozonation were calculated, and they were found to be in the range of 1.42 × 10 to 3.35 × 10 s for pH 5-11. The kinetic parameters for adsorption were calculated for the pseudo-first-order, pseudo-second-order, and Elovich models. The fit of the pseudo-first-order kinetic model to the experimental data was the best.
在本研究中，采用基于臭氧的高级氧化与活性炭吸附相结合的方法来处理制药工业废水。臭氧是一种选择性氧化剂，但羟基自由基（HO）的生成产生了比臭氧更强的非选择性氧化剂。制药工业产生的废水主要含有抗癌药物、抗精神病药物和一些止痛剂。在pH值为5 - 11的条件下，过氧臭氧工艺在3小时内的化学需氧量（COD）降低效率为75 - 88.5%。在pH值为5 - 11的条件下，活性炭吸附在2.5小时内进一步将COD降低至85.4 - 92.7%。在臭氧化过程中，所有其他水质参数均显著降低（去除率>73%）。还改变了主要操作参数（系统pH值和HO浓度），并分析了它们的影响。计算了臭氧化的伪一级速率常数，发现在pH值为5 - 11时，其范围为1.42×10至3.35×10 s。针对伪一级、伪二级和埃洛维奇模型计算了吸附的动力学参数。伪一级动力学模型对实验数据的拟合效果最佳。
