二氧化碳和天然气经过微波等离子体直接转化成C2烃

二氧化碳和天然气经过微波等离子体直接转化成Ｃ２烃陈栋梁雷正兰刘万楹＊⒇张承聪洪品杰戴树珊（中国科学院成都有机化学研究所，成都，６１００４１）（云南大学化学系，昆明，６５００９１）二氧化碳和甲烷都是很稳定的非极性分子，要使其分子活化，发生化学反应，转化...     

一氧化碳和甲烷在微波等离子体下直接转化成低碳烃(英文)

本文报道了微波等离子体下（２．４５ＧＨｚ）一氧化碳和甲烷直接转化成低碳烃的一种新方法。研究了影响产物分布的几个因素：微波输入功率、反应物比例及体系压力。乙炔和乙烷是主要有机产物。随着微波输入功率的增加和体系压力或ＣＨ４／ＣＯ比例的降低，乙炔含量增加，乙烷含量减少。反应中有少量乙烯和Ｃ３烃生成。没有检测到Ｃ４及含氧有机化合物。     

微波等离子体下甲烷偶联制乙炔的研究

通过优化设计矩形波导谐振腔微波化学反应器,可以大幅提高微波等离子体下甲烷转化率（最高为93．7％）、C2烃收率（最高为91．0％）和乙炔收率（最高为88．6％）．且优化后,在实验的压强范围内,甲烷转化率和C2烃收率较为稳定,C2烃主要是乙炔,其选择性都在90％以上．生成乙炔的能量产率和时空产率也都比较高．利用发射光谱法对微波等离子体下甲烷偶联制乙炔的反应进行了诊断研究,在300nm～750nm波长范围内激发态物种有：CH,C2,H2,Hα-根据反应产物和激发态物种从化学反应热力学和动力学上对反应机理进行了初步探索．     

微波诱导甲烷在活性炭/碳化硅上直接转化制C2烃

 在高功率脉冲微波辐照下甲烷可在常压条件下在活性炭/碳化硅和活性炭碳化硅等 三种催化剂上直接转化为C2烃。研究结果表明,当使用合适的微波作用条件时,微波加热与微波 等离子协同作用可使甲烷在多孔碳化硅担载的活性炭催化剂上以很高的转化率和选择性直接转化为乙炔,除单独的微波加热诱导作用和微波等离子催化作用外,转移反应机制可能是微波加热与微波等离子交互作用的具体表现形式,对促进甲烷向乙炔直接转化起了重要作用。     

反应器型式对甲烷低温等离子体转化制C2烃的影响

就不同反应器对甲烷常压低温等离子体转化制C2烃的影响进行了研究。结果表明,相同的甲烷停留时间和相同甲烷流率下,反应器A和B中反应的主要产物是乙炔,乙烯和乙烷的含量较少,积炭量较多;而反应器C和D中反应的主要产物为乙烷和丙烷,乙烯和乙炔含量较少,积炭量很少。反应积炭对反应器A中甲烷转化率影响很大,对于产物选择性影响不大,而对反应器C中的反应影响较小。根据产物分布可知,在反应器A和B中,由于电子具有很高的能量和密度,甲烷主要解离为碳原子;而在反应器C及D中,由于电子能量和密度较低,甲烷主要解离为CH3自由基。     

氧对非平衡等离子体甲烷脱氢偶联反应的影响

氧对非平衡等离子体甲烷脱氢偶联反应的影响雷正兰陈栋梁刘万楹＊（中国科学院成都有机化学研究所天然气开放实验室６１００４１）甲烷偶联形成Ｃ２烃是甲烷直接转化的重要反应。非平衡等离子体条件下甲烷脱氢偶联是获得Ｃ２烃的一种新方法。不用催化剂，利用非平衡等离子...     

滑动弧电极放电等离子体作用甲烷制C2烃的工艺

采用刀片式不锈钢电极放电反应器,以Ar气为稀释气,研究了等离子体作用下甲烷转化制C2烃的工艺条件。考察了CH4流量、高频电源输入电压和电极间距等参数对甲烷转化率、C2烃选择性、收率和反应表观能耗的影响。结果表明,增加CH4流量,表观能耗随之降低;当输入电压和电极间距较小时,甲烷转化率随输入电压和电极间距的增大而增大,但输入电压和电极间距过大时,C2烃收率明显下降,积碳严重。在CH4流量14 mL/min、Ar气流量60 mL/min、高频电源输入电压22 V、电流0.44 A、电极间距4 mm的优化条件下,甲烷最高转化率为43.1%,C2烃收率、选择性和表观能耗分别为40.1%、93.2%和2.41 MJ/mol。C2烃中不饱和烃的体积分数可达95%以上。     

低浊等离子体应用于甲烷的直接转化

简述了热等离子体裂解甲烷和冷等离子何强化甲烷转化的研究概况，着重从四个方面（反应机理和动力学、反应器的设计、等离子体与催化剂的协同作用、常压冷等离子体）评述了冷等离子体强化甲烷转化的国内外研究进展和发展趋势。     

非平衡等离子体条件下甲烷脱氢偶联反应

非平衡等离子体条件下甲烷脱氢偶联反应刘万楹，雷正兰（中国科学院成都有机化学研究所天然气化学开放实验室，６１００４１）甲烷直接转化是天然气化学研究和天然气化学利用的重要课题。甲烷偶联形成Ｃ２烃具有重要的学术和经济意义。甲烷氧化偶联研究已取得了一些有意义...     

低温等离子体应用于甲烷的直接转化

简述了热等离子体裂解甲烷和冷等离子体强化甲烷转化的研究概况，着重从四个方面（反应机理和动力学、反应器的设计、等离子体与催化剂的协同作用、常压冷等离子体）评述了冷等离子体强化甲烷转化的国内外研究进展和发展趋势。     

Catalysis Conversion Methane into C2 Hydrocarbons via Electric Field Enhanced Plasma

In this paper the effect of catalyst and carrier in electric field enhanced plasma on methane conversion into C2 hydrocarbons was investigated. Methane coupling reaction was studied in the system of continuous flow reactor on Ni, MoO3, MnO2 catalysts and different ZSM-5 carriers. The per pass conversion of methane can be as high as 22%, the selectivity of ethylene can be as high as 23.8%, of acetylene 60.8%, of ethane 5.4% and of total C2 hydrocarbons was more than 90%. ZSM-5-25 was the better carrier and MnO2 was the better active component. The efficiency of energy was as high as 7.81%.     

Zeolite-Enhanced Plasma Methane Conversion Directly to Higher Hydrocarbons Using Dielectric-Barrier Discharges

A zeolite-enhanced plasma methane conversion with pure methane feed using dielectric-barrier discharges (DBDs) at atmospheric pressure has been conducted. This plasma methane conversion over NaX has led to a selective production of light hydrocarbons. This revised version was published online in June 2006 with corrections to the Cover Date.     

Conversion of Methane to C2 Hydrocarbons via Cold Plasma Reaction

Direct conversion of methane to C2 hydrocarbons via cold plasma reaction with catalysts has been studied at room temperature and atmospheric pressure. Methane can be converted into C2 hydrocarbons in different selectivity depending on the form of the reactor, power of plasma, flow rate of methane, ratio of N2/CH4 and nature of the catalysts. The selectivity to C2 hydrocarbons can reach as high as 98.64%, and the conversion of methane as high as 60% and the yield of C2 hydrocarbons as high as 50% are obtained. Coking can be minimized under the conditions of: proper selection of the catalysts, appropriate high flow rate of inlet methane and suitable ratio of N2 to CH4. The catalyst surface provides active sites for radical recombination.     

大气压旋转螺旋状电极辉光放电等离子体催化甲烷偶联

采用新研制的具有旋转螺旋状电极的大气压辉光放电等离子体反应器催化甲烷偶联制碳二烃. 实验采用铜电极和不锈钢电极分别考察了输入电场峰值电压和甲烷、氢气进料流量等参数对甲烷转化率和碳二烃收率、选择性的影响. 在长时间连续反应无明显积碳的情况下, 最佳试验结果是电极材料为金属铜, 进料流量为60 mL•min^-1, V(CH₄ )/V(H₂)=1的条件下, 输入电场峰值电压为2.3 kV时, 甲烷转化率为70.64%, 碳二烃单程收率及其选择性分别为69.85%和 99.14%.     

Methane Decomposition and C2 Hydrocarbon Formation under the Condition of DC Discharge Plasma

The infrared emission spectra of methane, H, CH and C2 hydrocarbons in natural gas were measured. The processes of methane decomposition and formation of C2 hydrocarbons were studied. The experiment shows that methane decomposition can be divided into three periods as the reaction proceeds.In the first period, a large number of free radicals were formed. While in the last period, the formation of C2 hydrocarbons and the decrease of free radicals were observed. The time and conditions of methane decomposition and formation of C2 hydrocarbons are different.     

Platinum- and CuOx-Decorated TiO2 Photocatalyst for Oxidative Coupling of Methane to C2 Hydrocarbons in a Flow Reactor

Oxidative coupling of methane (OCM) is considered one of the most promising catalytic technologies to upgrade methane. However, C₂ products (C₂H₆/C₂H₄) from conventional methane conversion have not been produced commercially owing to competition from overoxidation and carbon accumulation at high temperatures. Herein, we report the codeposition of Pt nanoparticles and CuO_x clusters on TiO₂ (PC-50) and use of the resulting photocatalyst for OCM in a flow reactor operated at room temperature under atmospheric pressure for the first time. The optimized Cu_0.1Pt_0.5/PC-50 sample showed a highest yield of C₂ product of 6.8 μmol h⁻¹ at a space velocity of 2400 h⁻¹, more than twice the sum of the activity of Pt/PC-50 (1.07 μmol h⁻¹) and Cu/PC-50 (1.9 μmol h⁻¹), it might also be the highest among photocatalytic methane conversions reported so far under atmospheric pressure. A high C₂ selectivity of 60 % is also comparable to that attainable by conventional high-temperature (>943 K) thermal catalysis. It is proposed that Pt functions as an electron acceptor to facilitate charge separation, while holes could transfer to CuO_x to avoid deep dehydrogenation and the overoxidation of C₂ products.     

便携式微波等离子体离子化检测器气相色谱仪用于气体分析的研究

本文使用自制的便携式微波诱导等离子体离子化检测器气相色谱仪对可燃气体中N_2、O_2、H_2和CH_4的测定方法进行了研究。以氩气为载气和工作气体,考察了改进后的微波诱导等离子体离子化检洲器(MIPID)的工作参数对测定的影响。对煤气和乙炔中的O_2、N_2、H_2和CH_4进行了测定,分析结果与热导池检测器(TCD)的气相色谱法一致。讨论了高电离电位(>11.7ev)气体组分在MIPID中响应特性。     

常压辉光放电等离子体转化CH4制C2烃的研究

采用新型的旋转电极辉光放电反应器, 在常温常压下对辉光等离子体作用下的甲烷转化制C₂烃进行了研究. 在氢气共存条件下, 考察了反应器电极的结构、材料, 输入电场峰值电压和反应物流率等参数对甲烷转化率和C₂烃单程收率及其选择性的影响规律, 同时比较了不同反应器的能量效率. 结果表明: 在本实验条件下, 金属铜材料好于不锈钢, 螺旋形结构优于三排圆盘结构. CH₄转化率和C₂烃选择性和收率均随输入电场峰值电压的升高而增大, 随反应物流量的增加而减小. 从CH₄转化率、C₂烃的收率和选择性的指标来评价这些反应器, 采用旋转螺旋状铜电极反应器时最好, 当反应物流量为60 mL/min时, 甲烷最高转化率为77.31%, 对应的C₂烃收率和选择性分别为75.66%和97.88%; 当能量密度为800 kJ/mol时, 能效最高为13.5%.