Degradation of Acid Orange 7 in an Atmospheric-Pressure Plasma-Solution System(Gliding Discharge)

In this work,a plasma-solution system was applied to the degradation of Acid Orange 7(A07).The effects of initial concentration and type of feed gases(air,oxygen,nitrogen or argon) were studied.As the initial concentration increased from 100 mg/L to 160 mg/L,the discolouration rate of A07 decreased from 99.3%to 95.9%,whereas the COD removal rate decreased from 37.9%to 22.6%.Air provided the best discolouration and COD removal rates(99.3%and 37.9%,respectively).In the presence of a zero-valent iron(ZVI) catalyst,the A07 COD removal rate increased to 76.4%.The degradation products were analysed by a GC-MS,revealing that the degradation of the dye molecule was initiated through the cleavage of the-N=N- bond before finally being converted to organic acids.     

旋转滑动弧促进甲烷干重整制取合成气

实验考察了常温常压下,利用旋转滑动弧等离子体促进CH4-CO2重整制取合成气的效果,分析了放电电压、CH4体积分数和供气流量等参数对反应物转化率、产物选择性和经济效益等的影响.实验发现,CH4体积分数增加,会使CH4转化率升高,CO2转化率先增后减.流量增加,会使CH4、CO2转化率整体呈下降趋势.流量为12,L/min时,CH4、CO2最高转化率分别为43.78%、42.66%,H2、CO最高选择性分别为44.20%、32.48%,H2/CO体积比范围为0~1.56.单位摩尔量合成气所需电耗最低为195.06,kJ/mol,能量转化效率最高为46.535%.     

生活垃圾智慧焚烧的研究现状及展望

对生活垃圾收运、存储、焚烧处置和污染物排放控制等过程的智能化监测、控制和管理等国内外研究现状进行了梳理,分析了物联网、焚烧状态诊断、污染物在线监测和人工智能算法等技术在生活垃圾焚烧处置过程中应用的优缺点,并对未来生活垃圾智慧焚烧技术的发展做出了展望,建议对现有技术进行系统化耦合,并通过大数据分析及云计算平台,构建智能化反馈和优化模型,进一步开发智慧焚烧技术与装备。     

旋转滑动弧等离子体固氮的物理特性

采用旋转滑动弧等离子体（RGA）进行固氮实验研究. 为了考察在N₂/O₂气氛下放电的物理特性,利用光谱仪、高速摄影仪、示波器等进行研究,考察放电参数、气体体积流量对于氮气的振动温度、氮气的转动温度和电弧特性的影响,以及以上因素对于RGA固氮效果的综合影响. 实验结果表明,放电过程可以生产大量NO_x气体,通过光谱检测可以清晰观测到NO的γ带系、氮气第二正带系和氮气离子第一负带系. 增加放电的氧气体积分数,氮气的振动温度将升高,并伴随着固氮产出的提高;在一定范围内（10%~40%）,氧气体积分数提升在提升固氮效果的同时,对放电稳定性有不利影响. 综合分析表明,接近空气的放电气氛（氧气体积分数为20%）或直接采用空气放电,能够实现旋转滑动弧等离子体放电固氮的最佳效果.     

基于磁旋滑动弧等离子体催化的空气直接氧化固氮

以活性氧化铝（γ-Al₂O₃）为载体通过浸渍法制备不同质量分数（5%、7.5%和10%）的MoO₃/Al₂O₃催化剂,并进行等离子体催化空气的氧化固氮研究. 为了考察不同质量分数催化剂的结构差异,分别采用XRD、SEM和TEM表征催化剂的物理性质,结果表明催化剂结构稳定、分布均匀,有利于催化实验. 利用制备的MoO₃/Al₂O₃催化剂进行磁旋滑动弧等离子体耦合催化空气固氮实验,结果表明制备催化剂对固氮有促进作用,在最佳工况下, ${ {\text{NO}}_{{x}}}^{{-}}$的产出速率最高为1.17 mmol/min,相比同类研究中最高固氮效率 985 μmol /min有些许提升.     

Synthesis of vertical graphene nanowalls by cracking n-dodecane using RF inductively-coupled plasma-enhanced chemical vapor deposition

A facile and controllable one-step method to treat liquid hydrocarbons and synthesize vertical graphene nanowalls has been developed by using the technique of inductively-coupled plasma-enhanced chemical vapor deposition for plasma cracking of n-dodecane.Herein,the morphology and microstructure of solid carbon material and graphene nanowalls are characterized in terms of different operating conditions,i.e.input power,H2/Ar ratio,injection rate and reaction temperature.The results reveal that the optimal operating conditions were 500 W,5:10,30μl min^-1 and 800℃ for the input power,H2/Ar ratio,injection rate and reaction temperature,respectively.In addition,the degree of graphitization and the gaseous product are analyzed by Raman spectroscopy and gas chromatography detection.It can be calculated from the Raman spectrum that the relative intensity of ID/IG is approximately 1.55,and I2D/IG is approximately 0.48,indicating that the graphene prepared from n-dodecane has a rich defect structure and a high degree of graphitization.By calculating the mass loading and detecting the outlet gas,we find that the cracking rate of n-dodecane is only 6%-7%and that the gaseous products below C2 mainly include CH4,C2H2,C2H4,C2H6 and H2.Among them,the proportion of hydrogen in the outlet gas of n-dodecane cracking ranges from 1.3%-15.1%under different hydrogen flows.Based on our research,we propose a brand new perspective for both liquid hydrocarbon treatment and other value-added product syntheses.     

Co-synthesis of vertical graphene nanosheets and high-value gases using inductively coupled plasma enhanced chemical vapor deposition

One-step controllable synthesis of vertical graphene nanosheets (VGs) and high-value gases was achieved using inductively coupled plasma enhanced chemical vapor deposition (ICPECVD). The basic physical properties of the ICPECVD process were revealed via electrical diagnosis and optical emission spectroscopy. The coil current and voltage increased linearly with the augmenting of injected power, and CH, C₂, H₂ and H were detected at a wavelength from 300 to 700 nm, implying the generation of abundant graphene-building species. The morphology and structure of solid carbon products, graphene nanosheets, were systemically characterized in terms of the variations of operating conditions, such as pressure, temperature, gas proportion, etc. The results indicated that an appropriate operating condition was indispensable for the growth process of graphene nanosheets. In the present work, the optimized result was achieved at the pressure, heating temperature, applied power and gas proportion of 600mTorr, 800 °C, 500 W and 20:20:15, respectively, and the augmenting of both CH₄ and H₂ concentrations had a positive effect on the etching of amorphous carbon. Additionally, H₂ and C₂ hydrocarbons were detected as the main exhaust gases. The selectivity of H₂ and C₂H₂ , measured in exhaust gases, reached up to 52% and 8%, respectively, which implied a process of free radical reactions and electron collision dissociation. Based on a comprehensive investigation of spectral and electrical parameters and synthesized products, the reaction mechanism of collision, dissociation, diffusion, etc, in ICPECVD could be speculated, providing a probable guide for experimental and industrial applications.