以超聲波連續流裝置同時去除水中異丙醇與過氧化氫之研究

Simultaneously Removal of Isopropanol and H₂O₂ from Wastewater by Ultrasound in Continuous Reactor

楊和熙(Ho-Hsi Yang)

指導教授 ： 駱尚廉

國立臺灣大學/工學院/環境工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102233

摘要

過氧化氫 (Hydrogen peroxide, H₂O₂) 與異丙醇 (Isopropanol, IPA) 大量用於半導體製程中，且為了不額外產生污泥與擴大處理設備，提出在原有的設備中加裝超聲波，本研究為在連續流反應器中以超聲波搭配臭氧 (US/O₃) 去除過氧化氫與異丙醇，作為未來放大規模之前導實驗的參考。
本研究使用頻率20 kHz與功率500 W的超聲波，以批次實驗研究降解過氧化氫與異丙醇之反應動力學與自由基反應，探討在US/O₃連續流系統中進流量、氨氮、pH值、過氧化氫及異丙醇的初始濃度對去除率之影響，並觀察系統中氨氮變化與異丙醇之副產物，最終將US/O₃連續流系統應用在實場廢水中。
根據聲化學中空蝕現象 (Acoustic cavitation)，本系統降解過氧化氫與異丙醇的主要反應機制，過氧化氫為空蝕氣泡中熱裂解，異丙醇為氣泡的液氣界面處被氫氧自由基氧化。結果發現在鹼性環境中氨氮透過鹽析作用 (Salting out) 使過氧化氫有利於進入空蝕氣泡中熱裂解，產生更多氫氧自由基，在pH值為10中247 ppm的氨氮比0 ppm的氨氮，其過氧化氫與異丙醇去除率提升41.81%與36.74%，結果相比過去的研究，能更有效去除水中過氧化氫。將本系統應用在半導體廠廢水，在水力停留時間為33分鐘時，廢水中過氧化氫與異丙醇之去除率為80%及70%，證明本研究成功建立US/O₃連續流系統處理實廠廢水。

關鍵字

連續流 ； 過氧化氫 ； 異丙醇 ； 超聲波 ； 氨氮 ； 鹽析 ； 熱裂解 ； 氫氧自由基

並列摘要

Hydrogen peroxide (H₂O₂) and isopropanol (IPA) are widely used in semiconductor fabrication. In order to reduce the additional sludge and expand the treatment equipment, it is proposed to install ultrasound in the original equipment. It is the study that combined ultrasound with ozone (US/O₃) remove H₂O₂ and IPA in the continuous flow reactor before proceeding to application in the future.
A batch ultrasound reactor with the frequency of 20 kHz and a power of 500 W was used to the reaction kinetics and characterize the radical compositions in H₂O₂ and IPA degradation. In an advanced US/O₃ continuous flow system, it is necessary to discuss the effects of inflow rate, ammonia, pH value, initial concentration of H₂O₂ and IPA were systematically investigated to the removal efficiency of simultaneously remove H₂O₂ and IPA, and observed the transformations of ammonia and IPA by-products in this system. Finally, the feasibility and the effect of realistic wastewater were preliminarily found.
According to acoustic cavitation in sonochemistry, the primary reaction mechanism in H₂O₂ degradation was pyrolysis in cavities, and IPA was oxidated by hydroxyl radical (•OH) in the gas-liquid surface of cavities. The results in alkaline shows that ammonia nitrogen makes more H₂O₂ enter cavities to pyrolysis through salting out, and produces more •OH. At pH=10 with 247 ppm ammonia, the removals of H₂O₂ and IPA were increased by 41.81% and 36.74% respectively, which can remove effectively than the ammonia-free system. According to the best hydraulic retention time (33 minutes), the removals of H₂O₂ and IPA in realistic semiconductor manufacturing wastewater were 80% and 70% respectively, proving this study has successfully established the US/O₃ continuous flow system treating wastewater.

並列關鍵字

continuous flow reactor ； hydrogen peroxide ； isopropanol ； ultrasound ； ammonia nitrogen ； salting out ； pyrolysis ； hydroxyl radicals

參考文獻

Abdulloh, A., Supriyanto, G., Ningsih, O.W., (2019) Adsorption of isopropyl alcohol (IPA) in water using activated bentonite, IOP Conference Series: Earth and Environmental Science, 1 ed.

Adewuyi, Y.G. (2001) Sonochemistry: Environmental science and engineering applications. Industrial and Engineering Chemistry Research 40, 4681-4715.

Adewuyi, Y.G. (2005) Sonochemistry in environmental remediation. 1. Combinative and hybrid sonophotochemical oxidation processes for the treatment of pollutants in water. Environmental Science Technology 39, 3409-3420.

Anipsitakis, G.P., Dionysiou, D.D. (2004) Radical generation by the interaction of transition metals with common oxidants. Environmental Science Technology 38, 3705-3712.

Asakura, Y., Nishida, T., Matsuoka, T., Koda, S. (2008) Effects of ultrasonic frequency and liquid height on sonochemical efficiency of large-scale sonochemical reactors. Ultrasonics Sonochemistry 15, 244-250.