以微波強化高級氧化處理異丙醇廢水

Microwave-enhanced advanced oxidation processes for isopropyl alcohol wastewater treatment

陳氏芳瓊(TRAN THI PHUONG QUYNH)

指導教授 ： 童心欣

國立臺灣大學/工學院/環境工程學研究所/博士(2021年)

https://doi.org/10.6342/NTU202103927

摘要

異丙醇(Isopropyl alcohol, IPA)為半導體製程廠廢水中廣泛常見的污染物，因此本研究利用微波強化高級氧化處理(Microwave-enhanced advanced oxidation processes, MW-enhanced AOPs)並結合過氧化氫(H2O2)，比較在微波催化劑對異丙醇降解效率的影響。在 MW/H2O2 系統中反應90 分鐘內可將IPA完全降解，相較之下，單獨使用微波照射、單獨使用H2O2氧化，或以加熱(Thermal, TH)合併H2O2的系統，其去除IPA的效率分別為4.8%、6.1%和68.2%。IPA降解動力學在MW/H2O2和TH/H2O2系統中遵循擬一階動力反應，而其他系統為擬零階動力反應。在特定H2O2劑量下，降解效率隨著H2O2劑量增加而上升，過量的過氧化氫會捕捉氫氧自由基 而抑制IPA的氧化。MW/H2O2系統降解IPA的中間產物包含丙酮與短鏈有機酸等分別進行定性與定量分析，並以總有機碳的質量平衡來進行確認降解途徑。
對於此微波異相催化氧化系統，H2O2和活性碳(AC)的角色分別為氧化劑和微波吸收劑。本研究另外對於操作參數(過氧化氫濃度-[H2O2]、IPA初始濃度-[IPA]i、催化劑量- AC dosage)對 IPA 礦化的影響以Design-Expert® software version 12設計最佳化操作並以反應曲面方法論（Response surface methodology, RSM）進行優化。本研究所獲得最佳設計條件為：[H2O2] = 0.132 M, 活性碳劑量 = 108 - 123 g/L, [IPA]i = 36.82 - 100 mM, 照射時間= 4 min和照射溫度= 80°C，結果顯示活性碳劑量和初始 IPA濃度為主要去除IPA的影響因子。反應變化曲線中回歸線的R2 = 0.9948 和調整後的R2 = 0.9902顯示模式符合二次式適配。以MW/AC/H2O2組合反應系統相較於其他組合系統去除IPA效率最高和最快。最後，本研究針對高濃度IPA污水設計一上流式連續流微波催化反應器。

關鍵字

異丙醇 ； 微波 ； 高級氧化處理 ； 中央複合設計 ； 反應曲面方法論 ； 降解動力學 ； 降解途徑

並列摘要

Isopropyl alcohol (IPA) is a significant pollutant in wastewater of semiconductor manufacturing industry. This study investigated the degradation of IPA in microwave-enhanced advanced oxidation processes (MW-enhanced AOPs), where the simultaneous combination of MW irradiation and hydrogen peroxide (H2O2) was applied in the presence or absence of a catalyst. Complete elimination of IPA was noted in MW/H2O2 system within 90 minutes of irradiation. In comparison, only 4.8%, 6.1%, and 68.2% of IPA respectively removed in MW irradiation alone, H2O2 oxidation, and system using the combination of thermal (TH) and H2O2. The degradation kinetics of IPA followed the pseudo-first-order in MW/H2O2 and TH/H2O2 system, whereas the pseudo-zero-order reaction kinetics were observed in others. The degradation rates increased with increasing the H2O2 dose to a certain level. An excess H2O2 would trap the hydroxyl radicals to form weaker radicals that inhibit IPA oxidation. A series of degradation intermediates were identified and quantified, corresponding to acetone and short-chain organic acids. Subsequently, the degradation pathways of IPA in MW/H2O2 system were proposed and validated by the total organic carbon (TOC) mass balance.
For the microwave-assisted heterogeneous catalytic oxidation system, H2O2 and activated carbon (AC) work as an oxidant and MW-absorber, respectively. The effects of operating parameters (H2O2 concentration – [H2O2], initial IPA concentration – [IPA]i, and catalyst dosage – AC dosage) on the mineralization of IPA were investigated and optimized using response surface methodology (RSM) based on an experimental design generated by Design-Expert® software version 12. The estimated optimal working conditions in this study were as follows: [H2O2] = 0.132 M, AC dosage = 108 - 123 g/L, [IPA]i = 36.82 - 100 mM, irradiation time = 4 min, and irradiation temperature = 80°C. The findings indicated that the dosage of AC and the initial IPA concentration strongly affected the overall IPA removal. The values of R2 = 0.9948 and adjusted R2 = 0.9902 demonstrated that the response variability could be explained by the model expressing a satisfactory quadratic fit. The MW/AC/H2O2 system showed the fastest and highest IPA removal rate compared to other processes tested. Finally, a specially designed vertical microwave catalytic reactor operating in continuous flow mode aims to remove IPA in heavily contaminated wastewater.

並列關鍵字

isopropyl alcohol ； microwave ； advanced oxidation process ； central composite design and response surface methodology ； degradation kinetics ； degradation pathways

參考文獻

1. Wu, J.; Yang, J. S.; Muruganandham, M.; Wu, C. C., The oxidation study of 2-propanol using ozone-based advanced oxidation processes. Separation and Purification Technology 2008, 62 (1), 39-46.

2. Raghuvanshi, S.; Gupta, S., Growth kinetics of acclimated mixed culture for degradation of isopropyl alcohol (IPA). Journal of Biotechnology Biomaterials 2013, S13 (2).

3. Jammalamadaka, D.; Raissi, S., Ethylene Glycol, Methanol and Isopropyl Alcohol Intoxication. The American Journal of the Medical Sciences 2010, 339 (3), 276-281.

4. Matteucci, M. J., Chapter 89. Isopropyl alcohol. McGraw Hill: Poisoning Drug Overdose (sixth edition), 2012.

5. Turner, P.; Saeed, B.; Kelsey, M. C., Dermal absorption of isopropyl alcohol from a commercial hand rub: implications for its use in hand decontamination. Journal of Hospital Infection 2004, 56 (4), 287-290.