【摘要】 SF₆具有较高的温室效应潜在值（global warming potential, GWP）,未经处理排放到大气中会对环境产生影响。电力工业中SF₆的应用越来越广泛,废气排放量也高速增长。为减少电力工业中SF₆废气对环境的污染,基于TiO₂表面在紫外光照射下具有催化效应这一特性,设计了一套实验平台,研究了不同数量的Ti O₂催化剂和有H₂O参与时对常温常压下高浓度SF₆降解效果的影响,并通过仿真分析了SF₆气体分子在TiO₂表面的断键分解过程。研究结果表明:TiO₂作为催化剂能够有效提高SF₆的降解率。其中,未加TiO₂时SF₆在紫外光照3 h后的降解率仅为1.25%,加入8个TiO₂片时相同条件下3h降解率达到8.98%,降解产物主要有SO₂F₂、SiF₄、SF4以及SO₂;在此基础上,在SF₆气体中混入H₂O能把降解率提高到27.22%,降解产物主要有SO₂F₂、SiF₄、SF4、Si H₄、HF和SO₂。仿真计算结果表明TiO₂催化降解SF₆过程是把所需的能量细分为几个小的能量吸收过程,从能量吸收的角度解释了TiO₂催化降解SF₆的优势。研究结果可为SF₆的降解提供参考。更多还原

【Abstract】 SF₆ has a high global warming potential（GWP）, and will be harmful to the environment if the SF₆ is discharged into the atmosphere without treatment. The SF₆ is more extensively applied in the power industry and the exhaust emissions are also increasing rapidly. In order to reduce the environmental pollution of SF₆ exhaust gas in power industry, we designed a set of experimental platform based on the catalytic effect of TiO₂ surface under ultraviolet irradiation to study the effects of different amounts of TiO₂ and H₂ O participation on the degradation of high concentrations of SF₆ at normal temperature and pressure. At the same time, the process of catalytic decomposition of SF₆ gas molecule on TiO₂ surface was analyzed by simulation. The results show that TiO₂, as a catalyst, can effectively increase the degradation rate of SF₆.The degradation rate of SF₆ after ultraviolet irradiation for 3 hours in the absence of TiO₂ was only 1.25% and the degradation rate reached 8.98% with 8 pieces of TiO₂ added, and the main degradation products were SO₂ F₂, SiF₄, SF₄,and SO₂. Besides, H₂ O addition in SF₆ gas can increase the degradation rate to 27.22%. The main degradation products are SO₂ F₂, SiF₄, SF₄, SiH₄, HF, and SO₂. The simulation calculation results show that the TiO₂ catalytic degradation of SF₆ is to subdivide the required energy into several small energy absorption processes which explains the advantages of TiO₂ catalytic degradation of SF₆ from the perspective of energy absorption. The study can provide a reference for the degradation of SF₆.更多还原