利用自行開發之常壓氬氣微型電漿系統，來分解氣態二甲基硫(dimethyl sulfide，DMS)，轉變為其他物種，之後，使其可以經由水洗塔去除或是固體沉積方式處理，避免從工廠逸散至大氣中。此系統具有低耗能、常壓中操作、處理時間短等優點。本研究中，亦探討其分解機制及效能。
實驗中，以光學放射光譜儀及各式氣體分析儀檢測氬氣電漿、反應及生成氣體。氬氣電漿含有激發物種，如：Ar*、O*、OH*及e-。實驗結果顯示，混入濃度為400 ppm的DMS於氬氣微電漿中，處理6.7 × 10-4 sec後，會使DMS分解並轉為C*、C2*、CN*、CO*和CH*等激發物種。激發態物種離開處理系統後會再度結合，形成其他穩定的化合物或物種，而以固態顆粒和氣態相兩種型式存在。在固態顆粒方面，可能經由分解及聚集CH3S*、CH3*、CH2S*、CH2*等物種後，再結合形成結構複雜的物質。經處理一段時間後可在反應槽內側表面，觀察到黃色的沉積物；此成分經分析後，含有：烷基、C-S鍵及少量之C-O鍵和C-N鍵。在氣態相方面，分子量小的物種具活性，可能再結合成具較高熱力學穩定性物種，如：H2S、CS2、CO和H2等氣體物種。
在處理效能研究中，經由改變為雙電極系統可延長電漿反應的時間。例如：當功率為90 W之單電極系統，DMS由400 ppm可被分解至150 ppm；但在雙電極系統下，DMS可被完全分解為H2S、CS2及H2。如將雙電極系統的電漿處理功率提高至140 W，氣態產物中，鍵結能較低的H2S (92 kcal/mole)易被進一步分解，而使得相對90 W時H2S濃度降低；然而，CS2及H2的濃度則因為H2S的分解而增加。
有關氣體產物回收方面，利用NaOH溶液將H2S從氣態產物中分離，再利用活性碳將CS2收集，排出的H2可做為能源的再生利用。藉由上述DMS分解之研究，已初步建立微型常壓電漿系統對氣態廢棄物處理的反應機制。進一步可應用多重電極來控制有害氣體的排放，以促進友善的永續環境。

關鍵字：常壓、微電漿、二甲基硫、分解機制、氬氣、效能。

Custom-made atmospheric argon (Ar) micro-plasma system was employed to decompose dimethyl sulfide (DMS) into non-foul smell species. They were thereafter trapped by scrubber or solidification treatment to avoid spreading from the factory to the atmosphere. The as-designed system takes the advantages of low energy consumption, operation in atmospheric condition, short treatment time. In this study, the decomposition mechanism and efficiency were respectively discussed.
In the experiments, the compositions of argon plasma, reactants, and products were characterized using optical emission spectrometer and various gas-phase analyzers. Argon plasma contained excited species such as Ar*, O*, OH*, and e-. From the experimental results, DMS, with a concentration of 400 ppm mixed with argon plasma, was decomposed within the treatment time of 6.7 × 10-4 sec and converted into other excited species such as C*, C2*, CN*, CO*, and CH*. When gaseous products were away from the treatment system, the existing excited species tended to be recombined and formed some stabilized compounds or species, which were presumably survival in two states: solid particles and gaseous phases. The former ones were likely formed by the decomposition and agglomeration of CH3S*, CH3*, CH2S*, CH2*…etc., and then deposited upon the inner glass tube. After a period of time, the agglomerate was clearly observed like a distribution of yellow solid particles, which were furthermore analyzed as the combination of alkyl, C-S, a few C-O, and C-N. For the gaseous phases, low molecular-weight active species were mostly recombined into relatively thermodynamic stable species, like hydrogen sulfide (H2S), carbon disulfide (CS2), carbon monoxide (CO), and hydrogen (H2).
To improve the treatment efficiency, a double-electrode plasma system was utilized to extend the plasma reaction time. For example, with the applied power of 90 W, 400 ppm DMS in argon plasma was reduced to 150 ppm using a single-electrode plasma system, while the comparable quantity was completely degraded into H2S, CS2 and H2 using a double-electrode system. As increased the applied power of the double-electrode system to 140 W, the gaseous product H2S, owing to relatively low binding energy (92 kcal/mole), was easily decomposed and the concentration was decreased compared with 90 W, whereas the concentrations of CS2 and H2 were increased due to the decomposition of H2S.
In the case of recycling gaseous waste, NaOH solution was utilized to separate H2S from the gaseous products, while active carbon was subsequently used to form CS2 and H2. CS2 was collected by active carbon. The release of H2 was possibly used for energy regeneration. From the above measurements on the decomposition of DMS, the reaction mechanism of atmospheric micro-plasma system with respect to gaseous waste treatment was primarily established. Furthermore, a multiple-electrode system was anticipated to control the release of hazardous gaseous waste and promote a friendly and sustainable environment.

Keywords: Atmospheric, micro-plasma, dimethyl sulfide(DMS), decomposition mechanism, argon, efficiency.

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