Advances in H2 production from the aqueous-phase reforming of biomass-derived polyols：A review

生物质多元醇水相重整是一项正在发展的、很有前景的制氢技术。本文对近些年来涌现的生物质多元醇水相重整制氢研究进行了综述,讨论了多元醇水相重整反应热力学,介绍了反应动力学特征,并以此为基础对反应机理、催化剂体系以及工艺条件优化进行了总结。通过与蒸汽重整对比,指出了水相重整制氢技术的优缺点：优点是能耗低、工艺步骤较少、后处理简单;缺点是副反应多,收率低。最后,提出开发更为高效稳定的催化材料、降低催化剂制备成本和优化工艺条件将是未来研究工作的重点。     

Carbon-doped surface unsaturated sulfur enriched CoS2@rGO aerogel pseudocapacitive anode and biomass-derived porous carbon cathode for advanced lithium-ion capacitors

As a hybrid energy storage device of lithium-ion batteries and supercapacitors, lithium-ion capacitors have the potential to meet the demanding needs of energy storage equipment with both high power and energy density. In this work, to solve the obstacle to the application of lithium-ion capacitors, that is, the balancing problem of the electrodes kinetic and capacity, two electrodes are designed and adequately matched. For the anode, we introduced in situ carbon-doped and surface-enriched unsaturated sulfur into the graphene conductive network to prepare transition metal sulfides, which enhances the performance with a faster lithium-ion diffusion and dominant pseudocapacitive energy storage. Therefore, the lithium-ion capacitors anode material delivers a remarkable capacity of 810 mAh∙g^–1 after 500 cycles at 1 A∙g^–1. On the other hand, the biomass-derived porous carbon as the cathode also displays a superior capacity of 114.2 mAh∙g^–1 at 0.1 A∙g^–1. Benefitting from the appropriate balance of kinetic and capacity between two electrodes, the lithium-ion capacitors exhibits superior electrochemical performance. The assembled lithium-ion capacitors demonstrate a high energy density of 132.9 Wh∙kg^–1 at the power density of 265 W∙kg^–1, and 50.0 Wh∙kg^–1 even at 26.5 kW∙kg^–1. After 10000 cycles at 1 A∙g^–1, lithium-ion capacitors still demonstrate the high energy density retention of 81.5%.     

生物质气催化合成甲醇的热力学分析

由生物质气合成甲醇是一复杂反应系统,本文计算了其中各个反应的反应热和平衡常数与温度的关系.并以CO 21.5%、CO₂ 22.8%、H₂ 52.5%、N₂ 3.2%的气体模拟生物质气,用平衡常数法计算了在473.15～553.15 K、3～6 MPa下的平衡组成、碳的平衡转化率和所得甲醇的浓度.计算结果表明,这一体系中,主要是CO+H₂生成甲醇.低温和高压有利于提高碳的平衡转化率和甲醇的浓度.并用工业C306催化剂验证了上述规律的正确性.由于反应既受热力学控制,又受动力学控制,在3 MPa时碳的转化率在533.15 K时达到最大,接近平衡转化率.随压力升高,甲醇产率及液相产物中的浓度逐渐升高.     

基于水性聚氨酯和糠醛基DASA的可持续高物性双重隐形防伪涂层

将疏水的生物质基糠醛变色分子Donor-acceptor Stenhouse adducts(DASA)用十二烷基磺酸钠包裹后,将其加入到环境友好的阴离子型水性聚氨酯(Waterborne polyurethane,WPU)中,制备了一种革制品用高物性双重隐形防伪涂饰剂DASA-WPU.涂覆了该材料的合成革,经加热或紫...     

Hot Corrosion of an EB-PVD Thermal-Barrier Coating System at 950°C

Model thermal-barrier coating (TBC) systems consisting of cast NiCrAlYsubstrates and electron-beam, physically vapor-deposited (EB–PVD)partially yttria-stabilized zirconia (PYSZ) coatings with three differentmicrostructures were tested in 1-hr cycles at 950°C under hot-corrosionconditions (sodium and sodium/potassium sulfates) likely to occur inbiomass-derived fuel-fired gas turbines. In contrast to conditionsinitiating Type I hot-corrosion attack, a modified test procedure wasused in this study where periodically salt-coated specimens were subjectedto an oxygen atmosphere while SO_x was omitted, thus taking into account theessentially sulfur-free biomass fuel-combustion atmosphere. For comparison,similar tests were conducted on bare MCrAlY-type alloys. TBC failure byspallation of the PYSZ coating was observed between 300 and 500 1-hrcycles. Irrespective of PYSZ microstructure and deposit chemistry, failurewas primarily induced by crack formation and propagation within thevoluminous oxide scale formed as a result of hot-corrosion attack of themetal, rather than degradation of the ceramic layer. Since the major attackmode of the TBC seemed to be hot corrosion of the bond coat, this paperhighlights degradation mechanisms and microstructures of uncoated bond-coatcompositions. On the basis of the present results, implications of thefailure mode of EB–PVD PYSZ on in-service components are discussed.     

Biomass-derived Porous Carbon Materials for Supercapacitor Electrodes: A Review

The development of renewable,cost-efficient,and environmentally friendly electrode materials with excellent performance is urgently needed for improving supercapacitors(SCs).Recently,biomass-derived porous carbons(BPCs)have received increasing attention due to their excellent physical and chemical properties,widespread availability,and low production cost.In this review,the progress in preparing BPCs and the properties of prepared BPCs are presented and discussed.In addition,the applications of BPCs as electrode materials for supercapacitors are also summarized.More importantly,the pore structure and surface properties of BPCs are all determining factors to improve electrochemical performance.Moreover,a high energy density and power density can be pursued by using composites based on BPCs as electrode materials,of which combining transition metallic oxide with BPCs is one of the most attractive selections.Therefore,rational design of BPCs with respect to the supercapacitor's performance should be conducted in the future.     

Facile preparation of morph-genetic SiC/C porous ceramic at low temperature by processed bio-template

A porous morph-genetic SiC/C ceramic material was fabricated using biomass-derived C template, Si powder, and Fe(NO₃)₃·9H₂O as the starting materials. The effects of heating temperature, and catalyst/Si mole ratio on the formation of SiC/C ceramic were investigated. In addition, the pore size distribution was obtained through pore size analysis, and the determination of oxidation resistance of SiC/C ceramics and C template was carried out by thermogravimetric analysis. The results show that copious amounts of SiC nanowires, which were distributed on the surfaces and interiors of the C template holes, were formed at 1300 °C with 4 wt% Fe as catalyst. The SiC nanowires significantly affected the oxidation resistance and microporous structures of the prepared materials. Moreover, a possible formation mechanism for the porous SiC/C ceramic was determined.     

Co/SiO_2催化剂上模拟生物质合成气F-T合成的实验研究

比较了工业合成气(A)(H_2:CO:N_2=64:32:4,vol%)和生物质合成气(B)(H_2:CO:CO_2:N_2=45:45:7:3,vol%)在Co/SiO_2催化剂上F-T合成的反应性能。在T=513K,P=2.0MPa,GHSV=1000h~(-1)的条件下,气体(A)和气体(B)的(H_2+CO)转化率X_((H_2+Co))和CH_4选择性S_(CH_4)分别为95.54%、41.24%和17.19%、12.25%。在反应产物的分布上,两种气体的C_(5+)烃选择性S_(C_(5+))分别为67.46%、80.62%,气体(B)的产物向高碳数烃类迁移。气体(B)100h稳定性实验表明:24h后反应活性和液态烃类选择性基本稳定,X_(CO)和C_(5+)收率平均值分别为29.13%、131.30g·m~(-3)(syngas)。与工业合成气相比,生物质合成气液态烃类选择性高。     

生物质炭基材料在有机催化转化中的应用

近年来,生物质因具有富碳可再生、储量丰富、环境友好、价格低廉等特点被作为原料广泛应用于制备生物质炭基材料。本文综述了以生物质为原料衍生炭基材料作为催化剂在有机转化反应中的相关研究进展,重点介绍了杂原子掺杂、金属杂化策略所制备炭基催化材料在液相催化加氢、氧化、偶联等有机转化反应中的催化性能,进而阐明了炭基催化剂与催化活性之间的构效关系。最后,本文总结了生物质炭基催化剂在有机催化反应中的优势,指出了目前生物质衍生炭基催化剂材料合成和有机转化研究领域面临的挑战,并对此领域的未来发展趋势进行了分析与展望。     

生物质衍生磁性碳基复合材料的制备及其吸波性能

为响应国家碳中和、碳达峰目标,解决磁性碳基复合材料制备方法繁杂、能耗高、环境不友好等问题,提出生物质衍生法制备碳基吸波材料的新策略.通过选取香菇为原料,铁盐为金属源,经吸附得到铁/香菇前驱体,后经高温煅烧得到Fe/Fe4 N/C复合材料,对材料的相结构、微观形貌、热稳定性、磁特性等理化性质进行表征,分析其吸波性能.研究...