High Efficient Decomposition of Environment-Polluting Gases in a Specific Reaction System

在特定反应体系中高效分解环境污染气体

基本信息

批准号：
10650772
负责人：
SHIMIZU Yasuhiro
金额：
$ 2.24万
依托单位：
Nagasaki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 1999
项目状态：
已结题

项目摘要

Our previous studies have revealed that Ar plasma could be generated from SiC ceramics under atmospheric pressure upon irradiation of microwave and this microwave-induced (MI) Ar plasma offered several advantages in decomposing trichlorotrifluoroethane (CFC113). The present study was directed to improving the MI Ar plasma processing.When LaィイD20.8ィエD2SrィイD20.2ィエD2MnOィイD23ィエD2 was used as an alternative trigger for MI Ar plasma generation, similar decomposition behavior of CFC113 could be obtained. Thus, we could confirm again that CFC113 could be decomposed more satisfactorily by MI Ar plasma, accompanied by low energy consumption and low concentration of partial decomposition products, than by its direct thermal decomposition or simple catalytic decomposition with LaィイD20.8ィエD2SrィイD20.2ィエD2MnOィイD23ィエD2.Cooperative decomposition of CFC113 was also conducted by the MI Ar plasma generated from SiC ceramics and LaィイD20.8ィエD2SrィイD20.2ィエD2MnOィイD23ィエD2 catalyst placed in the downstream of th … More e plasma zone. In comparison with the decomposition without the catalyst, the concentration of CClィイD22ィエD2FィイD22ィエD2 as a partial decomposition product in the effluent gas was approximately doubled in the microwave power range of 60-80 W, but the total concentration of partial decomposition products was decreased satisfactory above the microwave power of 100 W. Thus, it was revealed that CFC113 could be decomposed more efficiently by the cooperative decomposition. However, the decomposition efficiency decreased gradually with time, probably due to the degradation of the catalyst by HCl and/or HF produced from CFC113 in the plasma. It was suggested that the long-term stability of this reaction system could be improved by setting the catalyst (heated at 550℃) in the downstream of the plasma zone and then by removing both HCl and HF form the effluent gas before reaching the catalyst zone.The shape of the plasma generated from SiC ceramics was a streak, and therefore it is suggested that poor radical and/or ion bombardment to CFC113 is responsible for unsatisfactory decomposition efficiency of the plasma alone. In the next step, therefore, the effect of the successive double plasma reactors, namely, the usefulness of an additional plasma reactor for decomposing partial decomposition products produced by the first plasma reactor has been investigated. As a result, further improvement in decomposition efficiency could be realized.Based on the results obtained, future investigations should be directed to the development of the ceramic form of a plasma trigger with three-dimensional open-micropore structure. The generation of Ar plasma inside the micropores makes low-cost, high efficient and continuous decomposition of environment-polluting gases possible under atmospheric pressure. Less

我们之前的研究表明，在大气压下，微波照射下 SiC 陶瓷可以产生 Ar 等离子体，这种微波诱导 (MI) Ar 等离子体在分解三氯三氟乙烷 (CFC113) 方面具有多种优势。本研究旨在改善 MI。 Ar等离子体处理。当LaiD20.8D2SrD20.2D2MnOD23D2被用作MI的替代触发器时Ar等离子体的产生，可以获得与CFC113类似的分解行为，因此，我们可以再次证实，与直接热分解相比，MI Ar等离子体可以更令人满意地分解CFC113，并且伴随着低能耗和低浓度的部分分解产物。或简单的催化分解与放置在等离子体区下游的 SiC 陶瓷和 LaD20.8D2Sr D20.2 D2MnO D23 D2 催化剂产生的 MI Ar 等离子体一起协同分解 CFC113。在没有催化剂的情况下的分解中，在60-80W的微波功率范围内，流出气体中作为部分分解产物的CClD22D2FD22D2的浓度大约增加了一倍，但是在微波功率100W以上时，部分分解产物的总浓度令人满意地降低。由此可知，通过协同分解可以更有效地分解CFC113，但分解效率较低。随着时间的推移，催化剂的降解逐渐减少，这可能是由于等离子体中 CFC113 产生的 HCl 和/或 HF 的降解而减少。这表明可以通过设置催化剂（在 550 加热）来提高该反应体系的长期稳定性。 ℃），然后在到达催化剂区之前去除流出气体中的HCl和HF。SiC陶瓷产生的等离子体的形状是条纹，因此表明自由基和/或者对CFC113的离子轰击是单独等离子体的分解效率不令人满意的原因。因此，在下一步中，连续的双等离子体反应器的效果，即用于分解由第一等离子体产生的部分分解产物的附加等离子体反应器的有用性。因此，可以实现分解效率的进一步提高。根据所获得的结果，未来的研究应集中于开发陶瓷形式的等离子体触发器。三维开放微孔结构，微孔内产生Ar等离子体，使得环境污染气体在常压下低成本、高效、连续分解成为可能。