Weighting Variation of Water-Gas Shift in Steam Reforming of Methane
天然气蒸汽重整制氢技术研究现状
天然气蒸汽重整制氢技术研究现状王斯晗;张瑀健【摘要】甲烷水蒸汽重整是目前广泛应用的制氢方法,具有工艺成熟、装置运行可靠、经济性强、环保和资源合理利用等优点,在适应大规模生产方面具有不可比拟的优势,但面临着工业设备投资大及催化剂易积炭失活的问题.国内外对甲烷水蒸汽重整的重点研究方向是制备高活性、高稳定性和强抗积炭性能的催化剂以及研制低水碳比条件下应用的催化剂,有效降低能耗.甲烷水蒸汽重整催化剂分为非贵金属催化剂、负载贵金属催化剂和过渡金属碳化物及氮化物催化剂,这些催化剂均能在高空速下使反应达到热力学平衡,甲烷转化率和CO/H2选择性均很高.金属活性组分负载量、载体、助剂及负载过程对催化剂活性、稳定性和选择性有重要的影响.同时,在甲烷水蒸汽重整反应过程中,催化剂活性组分的烧结、重新组合以及催化剂表面的积炭均可以引起催化剂失活,其中,催化剂表面积炭是最主要的影响因素,积炭反应是发生C-H和C-C键断裂后的表面碳聚反应,可引起活性中心中毒,堵塞孔道,甚至使催化剂粉化.积炭反应的影响因素包括添加稀土金属氧化物、催化剂制备工艺和催化剂的载体.【期刊名称】《工业催化》【年(卷),期】2016(024)004【总页数】5页(P26-30)【关键词】石油化学工程;甲烷水蒸汽重整;制氢;积炭【作者】王斯晗;张瑀健【作者单位】东北石油大学,黑龙江大庆163714;中国石油石油化工研究院大庆化工研究中心,黑龙江大庆163714;中国石油石油化工研究院大庆化工研究中心,黑龙江大庆163714【正文语种】中文【中图分类】TE624.9+2;TQ426.95综述与展望CLC number:TE624.9+2；TQ426.95 Document code: A Article ID: 1008-1143(2016)04-0026-05H2具有热转化效率高、环境零污染、能量密度高和输送成本低等优点，是目前最具吸引力的清洁高效能源，在石油化工和动力燃料行业中均有广泛应用[1-2]。
VOC Gas Sensor (Model WSP2110) 操作手册说明书
VOC Gas Sensor(Model:WSP2110)ManualVersion：1.3Valid From：2014.05.01Zhengzhou Winsen Electronics Technology Co., LtdStatementThis manual copyright belongs Zhengzhou Winsen Electronics Technology Co., LTD. Without the written permission, any part of this manual shall not be copied, translated, stored in database or retrieval system, also can’t spread through electronic, copying, record ways.Thanks for purchasing our product. In order to let customers use it better and reduce the faults caused by misuse, please read the manual carefully and operate it correctly in accordance with the instructions. If users disobey the terms or remove, disassemble, change the components inside of the sensor, we shall not be responsible for the loss.The specific such as color, appearance, sizes &etc, please in kind prevail.We are devoting ourselves to products development and technical innovation, so we reserve the right to improve the products without notice. Please confirm it is the valid version before using this manual. At the same time, users’ comments on optimized using way are welcome.Please keep the manual properly, in order to get help if you have questions during the usage in the future.Zhengzhou Winsen Electronics Technology CO., LTDWSP2110 VOC Gas SensorProfileWSP2110 VOC gas sensor adopts multilayer thick film manufacturing technology. The heater and metal oxide semiconductor material on the ceramic substrate of subminiature Al 2O 3 are fetched out by electrode down-lead, encapsulated in metal socket and cap. Conductivity of the sensor is affected by the concentration of target gas. The higher the concentration is, the higher conductivity of sensor gets. Users can adopt simple circuit to convert variation of conductivity into output signal corresponding to gas concentration.FeaturesHigh sensitivity to organic gases such as toluene, benzene, methanal; quick response and resume; low power consumption, simple detection circuit, good stability and long life.Main ApplicationIt is used in automatic exhaust device, air cleaner in domestic occasion for harmful gas detection. Technical Parameters Stable1.Fig1.Sensor S tructureBasic CircuitFig2. WSP2110 Test CircuitInstructions: The above fig is the basic test circuit of WSP2110.The sensor requires two voltage inputs: heater voltage (V H ) and circuit voltage (V C ). V H is used to supply standard working temperature to the sensor and it can adopt DC or AC power, while V RL is the voltage of load resistance R L which is in series with sensor. Vc supplies the detect voltage to load resistance R L and it should adopts DC power.Description of Sensor CharactersFig5.Responce and ResumeFig6.Linearity curveR s /R 0R s /R s 0Fig3.Typical Sensitivity CurveRs means resistance in target gas with different concentration, R 0 means resistance of sensor in clean air. All tests are finished under standard test conditions.Fig4.Typical temperature/humidity characteristicsRs means resistance of sensor in 10ppm toluene under different tem. and humidity. Rso means resistance of the sensor in clean air under 20℃/55%RH. Output Voltage (V)Output Voltage (V)Concentration (ppm)Time(s)Air AcetoneTolueneMethanal Methane Alcohol Concentration (ppm)Fig7.long-term Stability of WSP2110NOTE: Test is finished in standard test conditions, the abscissa is observing time and the ordinate is V RL .Cautions1 .Following conditions must be prohibited1.1 Exposed to volatilizable organic silicon steamSensing material will lose sensitivity and never recover if the sensor absorbs organic silicon steam. Sensors must be avoided exposing to silicon bond, fixature, silicon latex, putty or plastic contain silicon environment. 1.2 High Corrosive gasIf the sensors are exposed to high concentration corrosive gas (such as H 2S, SO X , Cl 2, HCl etc.), it will not only result in corrosion of sensors structure, also it cause sincere sensitivity attenuation. 1.3 Alkali, Alkali metals salt, halogen pollutionThe sensors performance will be changed badly if sensors be sprayed polluted by alkali metals salt especially brine, or be exposed to halogen such as fluorine.1.4 Touch waterSensitivity of the sensors will be reduced when spattered or dipped in water.1.5 FreezingDo avoid icing on sensor’s surface, otherwise sensing material will be broken and lost sensitivity. 1.6 Applied higher voltageApplied voltage on sensor should not be higher than stipulated value, even if the sensor is not physically damaged or broken, it causes down-line or heater damaged, and bring on sensors’ sensitivity characteristic changed badly. 1.7 Voltage on wrong pinsAs Fig8,Pin 1&2 connects to heater circuit, Pin 3&4 connects to measuring circuit; Under the requested conditions, heating and measuring can use the same power circuit.NOTE: the two pins near the protuberance mark is heating electrode.Output Voltage (V)Time (day)ToluenePin 1&2 is heating electrode,Pin 3&4 is measuring electrode.Protuberance MarkFig8.Pin Schematic Diagram2 .Following conditions should be avoided2.1 Water CondensationIndoor conditions, slight water condensation will influence sensors’ performance lightly. However, if water condensation on sensors surface and keep a certain period, sensors’ sensitiv e will be decreased.2.2 Used in high gas concentrationNo matter the sensor is electrified or not, if it is placed in high gas concentration for long time, sensors characteristic will be affected. If lighter gas sprays the sensor, it will cause extremely damage.2.3 Long time storageThe sensors resistance will drift reversibly if it’s stored for long time without electrify, this drift is related with storage conditions. Sensors should be stored in airproof bag without volatile silicon compound. For the sensors with long time storage but no electrify, they need long galvanical aging time for stability before using.The suggested aging time as follow:Stable2.2.4 Long time exposed to adverse environmentNo matter the sensors electrified or not, if exposed to adverse environment for long time, such as high humidity, high temperature, or high pollution etc., it will influence the sensors’ performance badly.2.5 VibrationContinual vibration will result in sensors down-lead response then break. In transportation or assembling line, pneumatic screwdriver/ultrasonic welding machine can lead this vibration.2.6 ConcussionIf sensors meet strong concussion, it may lead its lead wire disconnected.2.7 Usage Conditions2.7.1For sensor, handmade welding is optimal way. The welding conditions as follow:●Soldering flux: Rosin soldering flux contains least chlorine●homothermal soldering iron●Temperature：250℃●Time：less than 3 seconds2.7.2If users choose wave-soldering, the following conditions should be obey:●Soldering flux: Rosin soldering flux contains least chlorine●Speed: 1-2 Meter/ Minute●Warm-up temperature：100±20℃●Welding temperature：250±10℃●One time pass wave crest welding machineIf disobey the above using terms, sensors sensitivity will reduce.。
Fluent流体数值模拟软件中英对照
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Modeling of microreactor for methane dry reforming Comparison of Langmuir–Hinshelwood kinetic
CH4þCO242H2 þ 2CO
(1)
Synthesis gas production via CO2 (dry reforming) of natural gas (mostly CH4) has attracted increasing attention within the past decade since both are greenhouse gases and the possibility of conversion to more useful base chemicals via the FischereTropsch reaction is appealing (Foo et al., 2012). Dry reforming (DR) process becomes advantageous compared to steam reforming or partial oxidation for syngas production, since H2/CO product ratio (theoretically equals to one) is suitable for its further use in the production of oxygenated compounds and liquid hydrocarbons by the FischereTropsch synthesis using iron catalysts (Serrano-Lotina et al., 2012). Dry reforming's high endothermicity is the subject of
article info
Article history: Received 17 April 2014 Received in revised form 13 June 2014 Accepted 14 June 2014 Available online
逆水煤气变换(RWGS)催化剂研究进展
2017年第36卷第7期 CHEMICAL INDUSTRY AND ENGINEERING PROGRESS·2473·化 工 进展逆水煤气变换（RWGS ）催化剂研究进展代必灿1，周桂林1，2（1重庆工商大学环境与资源学院，催化与环境新材料重庆市重点实验室，重庆400067；2废油资源化技术与装备教育部工程研究中心，重庆400067）摘要：CO 2经逆水煤气变换（RWGS ）反应制得合成气（CO 和H 2），通过费托反应合成C x H y 燃料和含氧化学品，将对环境与未来能源结构产生重大影响，且催化剂起着决定性作用。
本文概述了RWGS 反应催化剂体系研究现状，详细介绍了Pt 、Pd 、Cu 、Ni 和Fe 基等催化剂的RWGS 反应性能，尤其是对金属与载体间的相互作用、制备方法和掺杂元素的电子效应等对相应催化剂的RWGS 反应性能进行了分析，进而探讨了Ce 基催化剂在RWGS 反应中的应用。
通过催化剂活性组分的优化能有效地调控相应催化剂的RWGS 反应性能，实现CO 2有效氢化还原制得合成气，为RWGS 反应工业化奠定基础。
最后对比总结了贵金属与非贵金属催化剂在制备方法、反应条件及RWGS 反应性能间的差异，提出新型催化剂材料开发是RWGS 反应工业化应用的关键。
关键词：二氧化碳；催化剂；合成气；逆水煤气变换；资源化中图分类号：TQ073；O643.36 文献标志码：A 文章编号：1000–6613（2017）07–2473–08 DOI ：10.16085/j.issn.1000-6613.2016-2074Perspective on catalyst investigation for reverse water-gas shift reaction（RWGS ）DAI Bican 1，ZHOU Guilin 1，2（1Chongqing Key Laboratory of Catalysis & Environmental New Materials ，College of Environment and Resources ，Chongqing Technology and Business University ，Chongqing 400067，China; 2Engineering Research Center for Waste OilRecovery Technology and Equipment ，Ministry of Education ，Chongqing 400067，China ）Abstract ：CO 2 can be converted into syngas via reverse water-gas shift （RWGS ）reaction ，followed by the F-T reaction to produce C x H y fuels or oxygenated chemicals ，which have a significant impact on the environment and the energy structure of the future society and the catalyst plays a key role. The catalyst systems of RWGS reaction are reviewed ，especially for the effect of interaction between metal and support ，the preparation methods ，and the electronic effect of doping elements on RWGS reaction performance of the corresponding catalyst are analyzed. Further ，the application of Ce-based catalyst in RWGS reaction was discussed. Optimizing the active component can effectively improve the RWGS reaction performance of the corresponding catalysts for the hydrogenation reduction of CO 2 into syngas ，and provide a foundation for the industrialization of RWGS reaction. The differences between noble metal and non-noble metal catalysts are also evaluated from points of the preparation methods ，reaction conditions ，and RWGS reaction performance. The development of novel catalyst material is the key to the industrial application of the RWGS reaction.Key words ：carbon dioxide ；catalyst ；syngas ；reverse water-gas shift reaction ；resource utilization第一作者：代必灿（1991—），女，硕士研究生。
羧酸改性HKUST-1提高甲烷吸附容量
羧酸改性HKUST-1提高甲烷吸附容量韩强;杨璐彬;程振飞;刘纪昌;汪成;欧苏慧;汪瑜懿;简雨培;杨小娟;王紫竹【摘要】为提高吸附材料对甲烷的吸附容量,采用溶剂热法合成了金属有机骨架材料HKUST-1,并进行了改性研究.HKUST-1的优化合成工艺条件为:原料摩尔比n(Cu(NO3)2·3H2O):n(H3BTC):n(DMF):n(C2H5OH):n(H2O)=1.7:1:46:60:100,晶化温度为80℃,晶化时间24 h.合成HKUST-1在25℃、3.5 MPa下的甲烷吸附容量为11.9 mmol/g.乙酸改性HKUST-1可以提高甲烷吸附容量,当反应母液中VHAc/Vsolvent=5.8％时,合成HAc-HK-1(5.8％)的甲烷吸附容量达到12.6 mmol/g.分子模拟结果表明,加入乙酸可以调控HKUST-1晶体孔道结构,增大比表面积和孔容,提高甲烷吸附容量.【期刊名称】《化工学报》【年(卷),期】2018(069)011【总页数】8页(P4902-4909)【关键词】HKUST-1;金属有机骨架材料;甲烷;天然气吸附储存【作者】韩强;杨璐彬;程振飞;刘纪昌;汪成;欧苏慧;汪瑜懿;简雨培;杨小娟;王紫竹【作者单位】化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237;化学工程联合国家重点实验室,华东理工大学,上海 200237【正文语种】中文【中图分类】TE821引言天然气吸附储存技术（adsorption natural gas,ANG）的研究是天然气分布式储存的基础，对天然气汽车的市场化推广具有重要意义。
甲烷干重整Ni基催化剂失活及抑制失活研究进展
CHEMICAL INDUSTRY AND ENGINEERING PROGRESS 2018年第37卷第10期·3850·化 工 进展甲烷干重整Ni 基催化剂失活及抑制失活研究进展阮勇哲，卢遥，王胜平（天津大学化工学院，绿色合成与转化教育部重点实验室，天津化学化工协同创新中心，天津 300072） 摘要：使用甲烷和二氧化碳为原料，通过甲烷干重整反应可以将其转化为合成气。
由于此反应可以利用甲烷和二氧化碳这两种温室气体，因而近年来受到了研究人员广泛的关注。
其中，反应所使用的Ni 基催化剂由于其较高的活性和较低的成本得到了较为深入的研究。
针对甲烷干重整Ni 基催化剂，本文简要介绍了几种常用的制备方法，并指出了在反应条件下存在的活性组分Ni 的烧结和积炭的生成这两个问题，还详细分析了其各自的影响因素。
另外，还从使用特殊载体、添加助剂以及构造特殊结构三方面阐述了甲烷干重整Ni 基催化剂的失活解决方案，并指出解决催化剂的烧结和积炭问题是当前该领域的研究重点。
关键词：甲烷干重整；Ni 基催化剂；烧结；积炭中图分类号：O643.36；TE64 文献标志码：A 文章编号：1000–6613（2018）10–3850–08 DOI ：10.16085/j.issn.1000-6613.2017-2241Progress in deactivation and anti-deactivation of nickel-based catalysts formethane dry reformingRUAN Yongzhe , LU Yao , WANG Shengping(Collaborative Innovation Center of Chemical Science and Engineering, Key Laboratory for Green Chemical Technology,School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China)Abstract ：Methane and carbon dioxide can be converted to syngas through dry reforming of methane. This reaction has attracted more and more attention because the two greenhouse gases CH 4 and CO 2 are utilized. The nickel-based catalysts have been studied extensively because of their high activity and low cost. In this review, several methods for preparation of nickel-based catalysts are briefly introduced. The sintering of nickel and carbon deposition are the two main problems of the nickel-based catalysts and the causes are discussed in detail. In addition, the approaches of anti-deactivation are introduced including using special support, adding auxiliary agent and constructing special structure. It is pointed out that how to solve the problems of catalyst sintering and carbon deposition is the focus of current research in this field.Key words ：dry reforming of methane ；nickel-based catalysts ；sintering ；carbon deposition合成气是化学工业的重要产品和原料，目前生产合成气的原料主要为煤、石油和天然气，而相比于另外两种方法，天然气制合成气由于其清洁环保的特点引起了人们的广泛关注。
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WeightingVariationofWater-GasShiftinSteamReformingofMethaneoverSupportedNiandNi-CuCatalysts
Ta-JenHuang,*Tien-ChunYu,andShih-YaoJhaoDepartmentofChemicalEngineering,NationalTsingHuaUniVersity,Hsinchu,Taiwan300,R.O.C.
Inthiswork,catalystsof2wt%Nisupportedonsamaria-dopedceria(SDC),gadolinia-dopedceria,andR-Al2O3,aswellasSDC-supportedNi-Cucatalystswith0.5wt%NiorCuandadditionof0.01-0.1wt%
CuorNiwereprepared.Activitytestsforsteamreformingofmethaneoverthesecatalystswerecarriedoutattemperaturesof673-823K.Amethodforanalyzingtheweightingofthewater-gasshift(WGS)activityinsteamreformingisproposed.Theeffectsoftemperature,support,andNi-CuratioontheWGSweightingvariationswerestudied.TheresultsindicatethattheweightingoftheWGSactivitydecreaseswithincreasingtemperature.TheextentofthevariationoftheWGSweightingislargerwithdopedceriaasthesupportthanwithR-Al2O3.TheadditionofCuintoaNicatalystenhancestheWGSactivity,andthisenhancementeffect
canbequantitativelyrelatedtotheamountofthebimetallicCu-Nispecies.ThesimpleanalysisofWGSweightingisabletogivesomeideasontheoperationandcatalystdesignforachievingagoodWGSactivity.
IntroductionSteamreformingofmethanehasbeenemployedforlarge-scaleproductionofhydrogen.1-3Recently,thisreactionhasbecomeincreasinglyimportantasthefuelprocessingtechnologyforfuelcells.4TheoverallreactionforsteamreformingofmethaneisconsideredtobeHowever,reaction1isusuallyconsideredtooccurviathefollowingreactionstepswherereaction2isthemainreactionforthesteamreformingofmethaneandreaction3,i.e.,thewater-gasshift(WGS)reaction,issecondary.Theamountofcarbonmonoxideproducedviasteamreformingofmethaneisusuallyquitehigh,andthisisanindicationthattheWGSreactionislessactivethanmethanereaction2,becauseequalactivitiesofreactions2and3wouldmeannoCOproduction.Therefore,theweightingoftheWGSactivity,i.e.,theratiooftherateofreaction3tothatofreaction2,wouldbeusefulforestimatingtheamountofCOinthefinalproductfromthesteamreformingofmethane.ThisinformationwouldbeusefulforthedeterminationofthedownstreamprocessesnecessarytoreducetheCOconcentration,especiallyforuseinproton-exchangemembranefuelcells.Nevertheless,althoughtheWGSreactionhasbeenwellstudied,5-7theabove-describedweightinganalysisoftheWGSactivityhasnotyetbeenreported,tothebestofourknowledge.ToreducetheamountofCOandsimultaneouslyproduceadditionalhydrogen,theprocessofmethanesteamreformingisusuallyfollowedbyhigh-temperatureand/orlow-temperatureWGStreatment.Forthis,Cu-ZnOcatalystiswell-knowntohaveverygoodlow-temperatureWGSactivity.Ontheotherhand,nickelcatalysthasbeenfoundtoexhibitpromisingcatalyticperformanceforthesteamreformingofmethane.3,8BecauseZnOisusuallyconsideredasapromoterforWGSactivityandtheCuspeciesisconsideredasthemaincatalyticagentintheCu-ZnOcatalyst,theadditionofCutothenickelcatalystmightbeabletoenhancetheactivityoftheWGSreaction(eq3)intheoverallreactionofmethanesteamreforming.Inaddition,theeffectofthesupportonthesteamreformingofmethaneovernickelcatalystshasbeenstudied.3,9Doped-ceria-supportednickelcatalystshavebeenshowntohavemuchhighercatalyticactivityforthesteamreformingofmethanethanalumina-supportedcatalysts;10thus,withdoped
ceriaasthesupport,theWGSactivitymightalsobeaffected.Ontheotherhand,theinternalsteamreformingofmethaneinsolidoxidefuelcells(SOFCs)hasrecentlybeenstudiedtoanincreasingextent.11-14Inthiscase,theCOconcentration
hastobereduced,andadditionalhydrogenmustbeproducedwithhighWGSactivityoftheSOFCanodebecausethereisnoseparateWGStreatment.Thus,theinformationontheWGSweightinginthesteamreformingofmethaneovertheSOFCanodeisimportantfortheoperationanddesignoftheanodesoastoachieveagoodWGSactivity.Inthiswork,catalystsofNisupportedonsamaria-dopedceria(SDC),gadolinia-dopedceria(GDC),andR-Al2O3,aswellas
catalystsofvariousNi-CuratiossupportedonSDCwereprepared.Activitytestsforthesteamreformingofmethaneoverthesecatalystswerecarriedoutattemperaturesof673-823K.AmethodforanalyzingtheweightingoftheWGSactivityinsteamreformingisproposed.TheresultsshowthattheWGSweightinginthesteamreformingofmethanevarieswithvariationsinthetemperature,support,andNi-CuratiooverthesesupportedNiandNi-Cucatalysts.
ExperimentalSectionPreparationofDopedCeria.Samaria-dopedceria(SDC)waspreparedbyacoprecipitationmethodfromreagent-grade(99.9%purity,StremChemical)metalnitratesSm(NO3)3‚6H2O
andCe(NO3)3‚6H2O.Appropriateamountsofsamariumnitrate
andceriumnitrate,correspondingtoanatomicmolarratioofSm/Ce)1:9,weredissolvedindeionizedwatertomake0.08Msolutions.HydrolysisofthemetalsaltstohydroxideswasobtainedbyslowlydroppingeachsuchsolutionintoNH4OH