对自主研制的甲醇合成催化剂进行工艺参数优化,同时根据实验结果对合成气条件下甲醇合成的反应机理进行探讨.实验采用16通道反应器,考察反应温度和接触时间对合成甲醇反应速率的影响,确定适宜的催化剂工艺条件.结果表明,在较长接触时间下,随着温度的升高,CO转化率、H2转化率和甲醇相对含量先升高后降低,CO2转化率降低.在较低温度下,CO2转化率随接触时间延长基本不变,表明甲醇中碳元素主要来自于CO,而CO2浓度处于水汽变换反应与加氢形成甲醇反应之间的平衡状态.

近年来,多级孔TS-1分子筛的合成引起了科学工作者的极大兴趣,本综述对多级孔TS-1分子筛的合成方法进行简单介绍,对不同合成方法的优劣势进行比较分析并对其未来发展进行展望.

通过浸渍法制备不同K2 CO3含量的K-CuCoAl催化剂,考察K含量对催化剂织构及低碳醇合成性能的影响.结果表明,K加入能中和催化剂表面的酸性;同时使催化剂对CO的线式吸附能力呈先升后降的趋势,相对应的产物中醇选择性也呈先升后降的趋势;K的负载会降低催化剂对CO的加氢反应活性.K含量对总醇收率影响呈火山型变化规律,最佳负载质量分数为0.9％.

The intrinsic kinetic behaviour of catalytic hydrogenation of acetic acid in vapour phase was studied over a multi-metallic catalyst. The rate expression was derived from the sequence of elementary reaction steps based on a Langmuir-Hinshelwood-model involving two types of active sites. Experiments were carried out in a fixed bed reactor, which is similar to an isothermal integral reactor designed to excluding the negative effects of internal and external diffusion. The reaction conditions investigated were as follow:reaction temperature 275-325 ºC, reaction pressure1.5-3.0 MPa, liquid hourly space velocity (sv) 0.3-1.2 h-1, molar ratio of hydrogen to acetic acid (H/AC) 8:20. The results show that conversion of acetic acid increases with increasing the reaction temperature and pressure, but decreases with increasing the space velocity and H/AC. Furthermore, reducing the reaction pressure and increasing reaction temperature, space velocity and H/AC can improve the reaction selectivity of acetic acid to ethanol. The established kinetic model results agreed with experimental results. The relative difference between the calculated value and the experimental value is less than 6 %. The values of model parameters are consistent with the three thermodynamic constraints. The study provided evidence that the intrinsic kinetic model is suitable both mathematically and thermodynamically, and it could be useful in guiding reactor design and optimization of operating conditions.

相较于普通的TiO2纳米材料,黑色TiO2纳米材料具有独特的晶体核/非晶核壳结构.该材料通过引入晶格缺陷改善TiO2的晶体结构来优化其电子能级结构,缩短禁带宽度,改善光学性能,其光响应范围从紫外区域扩展到红外区域,使得黑色TiO2纳米材料在能源和环境领域有着广泛的应用.本文主要介绍了近年来黑色TiO2纳米材料的性质、制备方法、改性方式、形貌控制、结构设计及以黑色TiO2为基体改性材料的催化原理,最后对黑色TiO2纳米材料的发展方向及实际应用前景(如在光降解有机污染物、光解水、燃料电池及光电化学传感器等方面)进行了展望.

以四丙基氢氧化铵(TPAOH)为模板剂,正硅酸乙酯(TEOS)为硅源,低成本硫酸钛(Ti(SO4)2)为钛源,在传统碱处理的基础上通过溶解-再结晶的后处理方法,制备得到了形貌规整且大小均匀的球形TS-1空心纳米颗粒,其颗粒尺寸约为200 nm.采用X射线衍射(XRD),N2吸脱附测试,扫描电镜(SEM),透射电镜(TEM)以及红外可见光谱(FTIR)等手段对不同后处理条件所得空心材料进行表征,结果表明,再结晶时间对空心材料的壁厚有明显的影响,且所得样品中Ti物种主要是以骨架内四配位形式存在的.同母体分子筛相比,空心材料在丙烯环氧化反应中体现出更好的催化活性.

The effects of the mass content of water, ethyl acetate and acetaldehyde on the performance of acetic acid hydrogenation to ethanol were studied in a fixed bed microreactor.Experiments were carried out at 285℃, 2.5MPa, 0.8mL/ (mL·h) of acetic acid hourly space velocity (SV), 16 of mole ratio of hydrogen to acetic acid (H/AC).The results show that the acetic acid conversion decreases 4.99％ with the increase of water content from 0to 10.0％, while the selectivity of ethanol shows little change.The acetic acid conversion decreases 3.93％ with the increase of ethyl acetate content from 0to 10.0％, while the ethanol selectivity increases 9.10％.When the ethyl acetate content is 4.4％, the amount of ethyl acetate remains unchanged after reaction.The acetic acid conversion decreases 2.02％ with the increase of acetaldehyde content from 0to 2.0％, while the ethanol selectivity increases 1.31％ and then shows little change.When the acetaldehyde content is 0.4％, the amount of acetaldehyde remains unchanged after reaction.Generally, the acetic acid conversion decreases with increasing the content of water, ethyl acetate and acetaldehyde.Furthermore, the selectivity of ethanol increases with increasing the content of ethyl acetate and acetaldehyde, and remains stable with the increase of water content.

对醋酸直接加氢制乙醇反应的热力学进行了研究.首先根据主副反应的反应物和产物的热力学参数,计算了主副反应的标准摩尔反应焓和标准平衡常数,并进一步研究了反应温度、反应压力以及氢酸的物质的量比对醋酸平衡转化率、乙醇选择性、乙酸乙酯选择性的影响.结果表明,醋酸直接加氢制乙醇的主反应为放热反应且放热量较大,同时放热量随着反应温度的升高而升高,而生成乙酸乙酯的副反应放热量较小且随反应温度的升高而降低;主反应及生成乙酸乙酯的副反应的标准平衡常数都随反应温度的升高而降低,特别是反应温度低于250T时,下降趋势显著;醋酸平衡转化率和乙醇选择性皆随着反应温度的升高而降低,随着反应压力或氢酸的物质的量比的升高而增加,乙酸乙酯选择性与之相反;分析结果表明该反应较适合的反应条件为200～300T,2～3MPa、氢酸的物质的量比为10～20.

Mn-based catalysts have been demonstrated to possess good low-temperature activity for NH3-SCR of NO,and have attracted increasing attention and broad application prospects.However,the catalysts suffer from poisoning deactivation easily when SO2 and H2O exist in the reactant gases.In this paper,the poisoning mechanism of SO2 and H2O on Mn-based catalysts has been expounded.Besides,the review focuses on the progress of research on improving the sulfur and water resistance of Mn-based catalysts,which is summarized in three aspects:adding transitional metals additives,controlling the morphology of catalysts and changing the preparation method.Finally,the existing problems of Mn-based catalysts are pointed out,the suggestions for improvement are prospected,and then the prospect of future development of Mn-based catalysts is put forward.

In this paper,recent progress in the research of Mn-based molecular sieves catalysts for low temperature NH3-SCR is reviewed,and the effects of the main components of MnOx,and additives on the catalyst properties are summarized.The mechanism of H2O and SO2 poisoning of Mn-based molecular sieve catalyst was analyzed.The mechanism of NH3-SCR reaction on Mn-based molecular sieve catalyst was summarized in detail.The application of molecular simulation in molecular sieve catalyst design was introduced.Finally,aiming at the problems existing in the low temperature NH3-SCR for manganese-based molecular sieves,the future development direction and research hotspots of this field are proposed.

Nanocrystal ZSM-5 aggregate with a SiO2/Al2O3molar ratio of 100 was prepared by low temperature hydrothermal crystallization,and was modified with different amount of MgO in order to investigate the effect of MgO amount

Ultra-low silica & hierarchical porous ZSM-5 was prepared in template-free hydrothermal System,with water glass as the silicon and Al2 (SO4)3 · 18H2O as aluminium sources,molar mass ratio SAR =n(SiO2)/n(Al2O3) =4O,pH =11.2,Na2O/SiO2 =0.18,H2O/SiO2 =43 and m(seed crystal)/m(SiO2) =0.16.The structures were characterized by 27A1 NMR,SEM-EDS,Py-IR,NH3-TPD,XRD and N2 adsorption/desorption test.The ZSM-5 crystals approximate cuboids less than four micron whose side faces display a vascular bundle shape through the SEM detection.EDS analyses revealed that the SAR distribution around the crystals surface is notable un-uniform:SAR values of top and bottom surfaces are 20,while that of the side surface is about 13.Acid analyses by NH3-TPD and Py-IR indicated the ultra-low SAR Na-ZSM-5 is of considerable quantity(1.9 mmol · g-1) of weak acid,and that is dominated by Lewis acid.N2 adsorption-desorption experiments means that the molecular sieve synthesized in this study could be identified as an ultra-low SAR & micro-meso hierarchical porous ZSM-5.

Aluminum is an important ingredient in the ternary Cu/ZnO/Al2O3 catalyst for methanol synthesis from syngas. The objective of this work is to investigate the effect of Al addition methods on the property of Cu/ZnO/Al2O3 catalyst. A series of Cu0.6Zn0.3Al0.1 catalysts with various Al-containing precursors were prepared by co-precipitation and fractional-precipitation methods. The catalyst samples were characterized by XRD, TG-MS, XRF, N2 physisorption and TPR. Results show that the Al addition methods have strong effect on the substitution of Cu by Zn in the subcarbonate lattice, leading to various performances of the obtained catalysts. Al addition with fractional precipitation performed higher substitution of Cu than that with the traditional co-precipitation method. And thus, it can be a promising method for preparing the Cu/ZnO/Al2O3 methanol synthesis catalyst.

Desilication liquor is one of the intermediate products of the fly ash aluminum-extraction industry by alkali system.Due to the inevitable introduction of iron ions in the production process of desilication liquor,utilization of the desilication liquor has been seriously restricted in areas who has strict limite of iron content,such as ultra clear glass.A method of FeSx-CuS Co-precipitation,was used to remove iron from fly ash desilication liquor.Taking Na2S as flocculant and CuSO4 · 5H2O as coagulant,influences of amounts and mixture ratio of the additive on iron-removal effects were investigated through series of experiments.The experimental results show that,iron existing in liquor can be effectively removed out through the following process:preheat the silicon liquor to 65 ～70 ℃ and add Na2S to react for 5 min;cool it down to 45 ℃,add into CuSO4 · 5H2O powder and keep this temperature for 30 min;finally static settle it for 24 hours.The optimum ratio (molar mass) of Na2S (300 times of Fe2O3) to CuSO4 is 3∶2,content Fe2O3 in the treated fly ash desilication liquorin was reduced below the lower detection limit,while copper ion residual was also minimum.That would benefit the utilization of the desilication liquor in ultra clear glass production.

The non-Mo-based catalysts--modified CeO2-ZrO2 were prepared,and the effects of preparation methods,proportions of components and thermal stability additives (La,Mg,Y) on the performances of the catalysts for high temperature sulfur-resistant methanationin were investigated in a fixed-bed reactor under the reaction conditions of 650℃,3MPa,GHSV of 5000h1 and the syngas with the H2/CO volume ratio of 1.0 and containing H2S of 0.6％ by volume.The results indicate that the catalysts prepared by co-precipitation (CeO2-ZrO2) have better activity and stability than the catalysts prepared by impregnation (CeO2/ZrO2) during the methanation reaction at high temperature.XRD results show that the co-precipitated CeO2-ZrO2 catalysts can form metal alloy.In the process of co-precipitation adding La additive can improve the thermal stability of the catalyst.

The maj or composition of white mud by-produced from alumina extraction from coal ash “direct acid-leaching method”developed by Shenhua Group,is SiO2 which accounts more than 70%.The White Mud has been considered as potential silicon based materials.The chemical and physical properties of White Mud have been analyzed.The iron methods have been introduced including carbonation process,manganese sand filter, and membrane separation technique.It is concluded that there are two main sources of iron in White Mud,one is Fe2 O3 and FeO which is not dissolved during the“one-step acid-leaching method”process,and would not dis-solved in the hot concentrated NaOH solution.The other is FeCl3 and FeCl2 which came from the dissolved ox-ide of iron in the“direct acid-leaching method”,and would react with hot concentrated NaOH solution to FeO-2 and FeO2-2 during the desilicification from White Mud.After dehydration,FeCl3 and FeCl2 reacted to Fe(OH)3 and Fe2 O3 which react with hot concentrated NaOH solution difficultly and so partly exist in nanoparticles.In the experimental conditions,the leaching rates of SiO2 in dehydrated White Mud is above 70%,the concentra-tions of silicon and iron are about 150.0 and 182.2 mg/L respectively,which reduced to about 30 mg/L (FeOSi (OH)3 2+)by carbonation,converted into Fe(OH)3 particles.Part of Fe(OH)3 particles precipitated with sili-cate,the other part existed in the solution as nanoparticles,which could be rarely removed by manganese sand filter,and membrane separation technique.The iron concentration of SiO2 produced by two-step-carbonation is 227 mg/kg.

采用浸渍法制备Y2O3促进的MoO3/ZrO2催化剂,通过H2-TPR和XRD对催化剂的物化性能进行表征,研究Y2O3对催化剂中活性组分MoO3与载体ZrO2之间相互作用力的影响.催化剂活性评价结果表明,助剂Y2O3在直接甲烷化反应中明显提高催化剂稳定性.在空速5000h-1、反应压力3.0 MPa和反应温度450℃条件下,反应800 h,催化剂活性保持稳定,具有优良的抗水合稳定性.

Coal will be the major source for power generation and basic chemicals production in the foreseeable years in China. Both sectors produce significant amounts of solid waste pollutants (fly ash), air pollutants (NOx, SOx), greenhouse gas emission (CO2) and waste water. The current technologies for each individual treatment or control cause high operation cost, waste of resources and large plant footprint. The proposed new technology is an integrated waste management system which will minimize energy consumption and maximize resource utilization. The technology is based on fly ash utilization which includes (1) the development of clean alumina extraction from fly ash technology;(2)the development of solid amine CO2 sorbent from fly ash and integrated De-SOx, De-NOx and De-CO2 process;(3)the development of functional material for waste water treatment from fly ash.

Effects of temperature, pressure, acetic acid( HAC) feeding rate and H2/HAC( GHSV or H2 flow) on the conversion of acetic acid, product selectivities and the productivity of ethanol in selective hydrogenation of acetic acid to ethanol were investigated in a fixed-bed reactor. The good stability of the lab-made catalyst was verified. The results show that the reaction rate of esterification and decarboxylation/ketonization are very fast. Selectivities of ethyl acetate and acetone are affected by the catalyst composition and reaction conditions. The hydrodecarbonylation of acetic acid to methane and the further conversion of ethanol can be avoided when the contact time of the reactants with the catalyst is less than 5 s. Optimum reaction conditions were found at 280℃, 2. 5 MPa, LHSV=0. 72 h-1, H2/HAC(mol ratio)=16, under which the selectivity of ethyl acetate could reach 6%. Life time test more than 900 h shows that the lab-made catalyst has a good potential for industrial application.

The intrinsic kinetics of sulfur-tolerant methanation catalyst NIC6 was studied. The catalyst NIC6 shows high activity at high temperature. An isothermal integral tubular reactor was employed to test the catalyst and get experimental data. The components of the feed gas and the reaction tail gas were analyzed by gas chromatography. The catalyst was tested under the reaction conditions of 460~550℃, 2.0~3.5MPa, H2S volume fraction of 0.4% and gas flow rate of 1.05~1.4mol/h. A power function kinetic model was established from the experimental data, and the activation energy and pre-exponential factor were obtained. The model testing show that the results are reasonable. The parameters are regressed significantly and the residual distribution is uniform.