高变质粉煤催化气化碱渣的煅烧脱碱

对福建五种高变质煤(永安、加福、尤溪、大田及永春煤)催化气化后的含碱灰渣进行煅烧脱碱研究.灰渣中碱含量随煅烧温度的升高及煅烧时间的延长而降低, 870 ℃煅烧30 min～40 min灰渣中碱含量趋于定值,脱碱率均达90%以上;X射线粉晶衍射及能谱分析表明,脱碱过程的实质是含碱灰渣中被活化的主要物质SiO2、Al2O3与灰渣中的碱性物质Na2O发生化学反应,生成难溶于水的钠铝复合硅酸盐的固相反应过程;表观动力学研究结果表明,该脱碱反应属一级反应,反应速率常数随煤渣中硅铝比的增加而增大,给出的反应速率常数随煤渣中硅铝比变化的关系方程,相关系数为0.99175,可用以预测任一已知含碱煤渣或不同Si/Al比的煤渣在不同煅烧温度下的脱碱反应速率常数,得出最佳的煅烧脱碱时间,为“煤催化气化-煅烧脱碱“集成式工艺工业应用提供基础数据.     

工业废液碱对福建无烟煤水蒸气催化气化的实验室研究

在Φ28mm的反应管中，采用工业废液碱用于福建无烟煤固定床水蒸气气化实验。结果表明，该废液碱对福建无烟煤气化有很强的催化活性。在添加3％－12％废液碱的情况下，碳转化率均比无催化剂时增加2.55倍－3．93倍，明显大于添加以Na2CO3为催化剂的碳转化率。同时该废液碱对煤气组成，产气量和煤气热值均有明显提高。在催化气化的同时加入适量的脱碱剂可极大地降低灰渣中的含碱量。     

以烯碱和烯盐酸两步处理脱除煤中矿物质和硫 Ⅱ.脱硫作用及机理

选用兖州、东林和南桐高硫煤以烯碱和烯盐酸两步处理，在考察脱矿物质效果的同时研究了脱硫作用及机理。南桐煤全硫含量Std为4.25%，在120－240℃以6W％NaOH水溶液处理，再在100℃以5W％HCl巡取，脱硫率从38.8%增加到62.4%，其中主要脱的是Ss和Sp,So变化很小。当在370℃进行碱处理后，东林煤有机硫的脱除率达到50.6%,兖州煤则达到57.3%。文中还 对无机硫和有机硫的脱除机理进行了初步研究。     

福建无烟粉煤纸浆黑液富氧流化床催化气化研究

在实验室小型流化床反应器中研究了福建龙岩无烟粉煤纸浆黑液富氧催化气化的特性，考察了纸浆黑液催化剂添加量不同时氧体积分数变化对碳转化率、产气率、煤气组成与热值的影响。结果表明，纸浆黑液催化和富氧气体燃烧的双重作用明显地提高了煤的碳转化率和煤气有效组成；纸浆黑液中钠碱对煤焦气化的催化与对煤灰分中SiO2和Al2O3等氧化物的熔制反应同时发生并存在着竞争；纸浆黑液中钠碱对高温碳与气化剂之间多种反应表现出不同程度的促进。龙岩无烟粉煤在纸浆黑液富氧催化气化时适宜操作条件是氧的体积分数40％和蒸汽/富氧比为1.4kg/m3～2.0kg/m3。碳转化率94％、煤产气率为3.62m3/kg、煤气热值为7.33mJ/m3。     

黏胶废液对福建无烟煤水蒸气催化气化的动力学和补偿效应

采用黏胶废液为催化剂,对福建尤溪无烟粉煤在常压热分析仪中的水蒸气催化气化动力学进行了研究。在850℃～950℃测定了黏胶废液催化剂添加量（NaOH浓度为计算基准）从0～12%时的碳转化率随气化时间的变化,表明黏胶废液具有提高碳转化率和气化速率的作用,同时确定了该黏胶废液催化剂的加载饱和浓度。基此得出的尤溪无烟粉煤水蒸气催化气化反应动力学符合缩芯模型,并给出相应的动力学参数。进而分析表明,该催化气化过程存在明显的补偿效应,最后给出黏胶废液对尤溪无烟粉煤水蒸气催化气化包括补偿效应的动力学方程。     

工业废碱催化剂MA与煤混合浸渍干燥的研究

以转筒干燥方式考察了福建无烟粉煤与工业废碱催化剂MA同时进行混合浸渍与干燥脱水的过程，讨论了煤的粒径，干燥温度，时间、气速、转筒转速、催化剂含量和转筒处理量等因素对煤与催化剂混合浸渍与干燥过程的影响。研究表明采用转筒干燥的方式,进口干燥空气温度在80 ℃～160 ℃、转筒处理量为214 kg/m3·h～1834 kg/m3·h、干燥气速0.12 m/s～0.30 m/s、干燥时间20 min内，混合物料的湿含量可降至<5%，且催化剂与煤浸渍充分均匀，满足流化床操作的要求，实现了最佳的催化气化效果。基于实验数据拟合了煤和废碱催化剂转筒干燥的传热系数方程，通过物料与能量衡算，模拟了混合物料连续干燥时沿转筒的湿含量的变化。     

碱金属碳酸盐在煤气化中的催化作用——Ⅳ.复合催化剂Na-M-Ⅱ的催化活性

添加复合催化剂Na-M-Ⅱ可使晋城无烟煤同水蒸汽反应的表观活化能从212.0降低到76.24M/mol,而添加K_2CO_3则仅降低到102.5 kJ/mol。在750℃和常压下所作的这一比较再次表明,前者更能促进碳-水蒸汽的气化反应。所以,在开发煤催化气化时,可以考虑不需要利用昂贵的钾化合物。     

燃烧与催化气化灰中铝溶出行为的研究

实验对比了燃烧灰与负载Na_2CO_3催化气化灰中Al的溶出行为,考察了Na_2CO_3负载量(0-15%,质量分数)和温度(600-1 000℃)对催化气化灰中主要矿物组成与Al溶出行为的影响。同时,采用XRD分析了燃烧灰、催化气化灰以及酸浸残渣的主要组成。结果表明,燃烧灰的主要组成为莫来石,而催化气化灰的主要组成为硅铝酸钠((Na_2O)_(0.33)NaAlSiO_4)。6 mol/L硫酸、60℃和30 min浸取条件下,燃烧灰的浸出率只有40%,而Na_2CO_3负载量为10%的催化气化灰的浸出率达到88%。催化气化灰更易于回收灰中的Al。     

福建无烟粉煤流化床混合气催化气化表观动力学的研究

在一模试流化床中,首次报道了福建劣质无烟粉煤（挥发分〈５％）采用工业副产碱盐为主制备的复合催化剂进行混合气催化气化的结果,指出这一复合催化剂适宜的添加饱和度为１０％;表观动力学实验表明在该添加饱和度下,使反应表观活化能由无催化剂时的Ｅａ＝７６．０３ｋＪ／ｍｏｌ降为Ｅａ＝４５．８３ｋＪ／ｍｏｌ（几乎降低了４０％）,并且在气化温度８５０℃条件下,其表观反应速率常数比无催化剂时提高２．７倍;在气化温度８５０－９００℃,催化剂浓度１０％的适宜操作范围,可获得产气率Ｖ＝３．７７－３．５８ｍ＾３／ｋｇ（１ｋｇ煤）,煤气热值ＱＬＨＶ＝５．３１＝６．０３ＭＪ／ｍ＾３与冷煤气效率η＝７９．７２＝８５．７３％的良好结果,这对劣质无烟粉煤催化气化生产燃料气与化工副产碱盐制取廉价催化的工业化实践具有重要的应用价值与可操作的现实意义。     

高灰煤小型流化床混合气催化气化研究

在内径28mm流化床中,对阳泉高灰煤在碱性催化剂（固碱和黏胶废碱液）作用下进行了混合气（空气/水蒸气）催化气化研究,两种碱性催化剂的适宜添加量均为6％。不加催化剂,气化温度830℃~900℃与900℃～920℃下,气化反应的表观反应级数n分别约为2/3与1/3;有催化剂（3％固碱）时,表观反应级数有两个明显的温度段,在830℃~860℃,催化气化的表观反应级数n=1;在860℃~920℃,催化气化的表观反应级数为n=1/3。     

Hydrogen storage over alkali metal hydride and alkali metal hydroxide composites

Alkali metal hydroxide and hydride composite systems contain both protic(H bonded with O) and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation increased with the increase of atomic number of alkali metals,i.e.,-23 kJ/molH2 for LiOH-LiH, 55.34 kJ/molH2 for NaOH-NaH and 222 kJ/molH2 for KOH-KH. These thermodynamic calculation results were consistent with our experimental results. H2 was released from LiOH-LiH system during ball milling. The dehydrogenation temperature of NaOH-NaH system was about 150℃; whereas KOH and KH did not interact with each other during the heating process. Instead, KH decomposed by itself. In these three systems, NaOH-NaH was the only reversible hydrogen storage system, the enthalpy of dehydrogenation was about 55.65 kJ/molH2, and the corresponding entropy was ca. 101.23 J/(molH2 K), so the temperature for releasing 1.0 bar H2 was as high as 518℃, showing unfavorable thermodynamic properties. The activation energy for hydrogen desorption of NaOH-NaH was found to be57.87 kJ/mol, showing good kinetic properties.     

Hydrogen storage over alkali metal hydride and alkali metal hydroxide composites

Alkali metal hydroxide and hydride composite systems contain both protic(H bonded with O) and hydridic hydrogen. The interaction of these two types of hydrides produces hydrogen. The enthalpy of dehydrogenation increased with the increase of atomic number of alkali metals,i.e.,-23 kJ/molH2 for LiOH-LiH, 55.34 kJ/molH2 for NaOH-NaH and 222 kJ/molH2 for KOH-KH. These thermodynamic calculation results were consistent with our experimental results. H2 was released from LiOH-LiH system during ball milling. The dehydrogenation temperature of NaOH-NaH system was about 150℃; whereas KOH and KH did not interact with each other during the heating process. Instead, KH decomposed by itself. In these three systems, NaOH-NaH was the only reversible hydrogen storage system, the enthalpy of dehydrogenation was about 55.65 kJ/molH2, and the corresponding entropy was ca. 101.23 J/(molH2 K), so the temperature for releasing 1.0 bar H2 was as high as 518℃, showing unfavorable thermodynamic properties. The activation energy for hydrogen desorption of NaOH-NaH was found to be57.87 kJ/mol, showing good kinetic properties.     

Thermal behavior of alkali metal azides in NaY-FAU zeolite

The thermal behavior of pure alkali metal azides and their mechanical mixtures with NaY-FAU zeolite was investigated by means of thermogravimetry and IR spectroscopy. LiN₃, KN₃, RbN₃ and CsN₃ were prepared from NaN₃ by ion-exchange. The pure azides exhibited low thermal stability, hindering the precise spectroscopic characterization in some cases. The decomposition of each azide in the zeolite took place above the temperature characteristic for the pure azide, demonstrating the stabilization of the azide in the zeolite cavities. This feature was the only common characteristic established for the azide/zeolite systems.The financial support of the National Science Foundation of Hungary (OTKA 1604/91) is gratefully acknowledged.     

Untersuchungen zur Existenz ternärer Amalgame der Alkalimetalle: Die Systeme KHg2?RbHg2 und NaHg2?CsHg2

Studies on the Existence of Ternary Amalgams of Alkali Metals: The Systems KHg₂-RbHg₂ and NaHg₂-CsHg₂ . The ternary systems KHg₂? RbHg₂ and NaHg₂? CsHg₂ are investigated by thermal analyses and X-ray methods. Both systems are quasibinary: Lattice constants and cell volumes of samples in the system KHg₂? RbHg₂ are in accordance with Vegards law (continous formation of mixed crystals). No ternary compound was detected in this system. NaHg₂? CsHg₂ however shows a peritectic decomposition at 300°C, which can be associated to the new ternary compound Na₂CsHg₆, crystallizing in the hexagonal system (a = 5.080(1) Å; c = 11.632(3) Å). Due to pronounced disorder the crystal structure of Na₂CsHg₆ cannot be determined in full details. In principal it corresponds to an ordered variant of the NaHg₂ structure (modified AlB₂ type) with a triple c-axis.     

Alkaline Activation of Metakaolin An Isothermal Conduction Calorimetry Study

The alkaline activation of metakaolin leads to high mechanical performance inorganic polymers. A JAF conduction calorimeter was used to follow the reaction of metakaolin with NaOH solutions. The alkaline activation of metakaolin to yield a cementitious material is an exothermic process involving three steps: an initial and very fast process of dissolution, which is strongly exothermic, followed by an induction period in which the heat exchange rate decreases, and finally an exothermic step of reaction reactivation in which cementitious materials precipitate and after which the heat exchange rate decreases. The calorimetric curves lead to the following findings: - The induction period is lengthened as the NaOH solution concentration and the liquid percentage increase. - The induction period is shortened as the temperature increases. - The total heat increases as the liquid percentage and the NaOH concentration increase. This revised version was published online in July 2006 with corrections to the Cover Date.     

Relaxation of Alkali Glass Exposed to an Electron Beam

Binary potassium and rubidium silicate glasses were irradiated with high-energy electrons. The changes induced in the glasses were observed as a decay of alkali X-ray signals with time. The decay curves displayed incubation periods, connected with changes of the transport mechanism. The electron exposures were interrupted relative to the incubation periods, next the glasses were annealed to enable easier relaxations, and successively irradiated again to finish the decay curve. Relaxation, which depends on the point of the decay curve at which exposure is interrupted, is calculated for the glasses. Relaxation was found to depend strongly on the interruption point with regard to the incubation period. The longer irradiation causes worse recovery of the structure during annealing, especially if the irradiation lasts longer than the incubation time. The larger ions and lower concentration also inhibit relaxation.     

加碱萃取精馏制取无水乙醇

乙醇-水体系存在共沸点,难以通过普通精馏方法制取高纯度乙醇,萃取精馏是分离共沸体系的有效途径。目前常用的萃取溶剂是乙二醇。在分离乙醇-水体系的过程中,将适当的盐类(醋酸钾)溶于乙二醇形成溶盐萃取剂,会有效提高溶剂的选择性。本文用萃取精馏方法并加入乙二醇分离效果更明显。     

腙型双冠醚的合成和性质Ⅱ.

４’－甲酰基苯并－１５－冠－５、４’－乙酰基苯并－１５－冠－５分别与肼和芳杂环二肼缩合得到五种新的腙型双冠醚．用电导法研究了它们与碱金属离子的配位性质．