煤集成共转化制备合成气工艺分析

众所周知,目前我国煤炭存在利用效率低,环境污染严重等问题,随着科学技术的发展,煤集成共转化制备合成气工艺得到了广泛发展,首先论述了我国煤集成共转化制备合成气工艺现状与反应机理,探讨了温度对煤集成共转化制备合成气工艺的影响,并提出了我国煤集成共转化制备合成气工艺的发展方向。

转化法制备硝酸钾微型实验的探究

该文介绍了一种在常规实验的基础上，把转化法制备硝酸钾实验设计为微型实验，可省去甘油浴，并对其中的热过滤部分进行改进，大大缩短了实验时间，操作简单、产率高、实验效果显著。

理化及生物转化稀有人参皂苷的方法

为了实现稀有人参皂苷的大批量生产,从生物、化学、物理3个角度综述稀有人参皂苷的制备方法,从催化剂、转化条件和制备效率等方面进行总结和分析。结果显示,生物转化具有效率高、环境友好等优点,其转化效率大多高于化学转化和物理转化。此外,在所有参与转化的底物中,人参皂苷Rb_(1)、Rb_(3)较容易被转化成稀有人参皂苷CK、Rh_(2)、Rg_(3)等,Rb_(1)、Rb_(3)转化生产稀有人参皂苷Rg_(3)、CK等已较为成熟和产业化,随着技术的不断进步,稀有人参皂苷的批量生产技术水平将不断提升。

玻璃板上氢氧化亚铁的制备及转化

石蕊溶液在硫酸亚铁和氢氧化钠溶液中会呈现出不同的颜色。通过改变硫酸亚铁溶液和氢氧化钠溶液的滴加顺序,在玻璃板上成功实现氢氧化亚铁的制备及转化。实验能够短时间内在玻璃板上清晰地呈现“白→灰绿→红褐”完整的变色现象,不仅有助于学生加深对氢氧化亚铁还原性的认识,而且有益于激发学生的学习热情以及培养科学探究与创新意识。

以“模块化+策略分解”锻炼解题思维——以部编版初中化学“物质转化与制备”一课教学设计为例

初中化学“物质转化与制备”内容的教学,需要梳理整理知识,结合实例进行解题思路引导。教学中建议进行模块化指导,分环节进行引导。本文将针对该部分知识进行教学梳理,提出相应的指导建议。

从技术到设备 生物质转化取得新突破

项目成果:农林生物质定向转化制备液体燃料多联产承担单位:中国林业科学研究院林产化学工业研究所我国是能源生产大国也是消耗大国,由于传统能源的存储量的限制和燃烧时产生的大量危害气体和温室气体等因素,越来越多的人将目光放到了新型能源——生物质的身上。近日。

SiGeAl-ITQ-13和SiAl(B)-ITQ-13分子筛的合成及其甲醇转化制烃催化性能（英文）

采用直接水热合成和后合成两种方法制备Al-ITQ-13分子筛,用于催化甲醇转化制备烃类化合物。采用XRD、27Al M AS NM R、NH3-TPD、Py-FTIR和SEM等技术对所合成样品进行了表征。结果表明,两种方法制备的Al-ITQ-13结晶度都较高,且晶体形貌为薄片。与ZSM-5相比,Al-ITQ-13在甲醇转化反应中显示出较高的丙烯选择性、较高的丙烯/乙烯产物比以及较好的催化稳定性。同时,由于后合成所得到的Si Al(B)-ITQ-13强酸量减少,其催化性能优于直接合成的Si Ge Al-ITQ-13。

常温常压制备甲酸获进展

最近,上海交通大学在35℃和常压条件下,实现了碱性水溶液中纤维素类生物质的高选择性氧化转化制备甲酸。该技术反应条件十分温和,在相对较短的8 h内葡萄糖却近乎完全转化,同时甲酸产率达到91.3%的新纪录。传统方法通常需要在90~300℃高温和2~8 MPa的压力下完成该转化。

构建生物质原料的化工体系

生物质作为自然界唯一的可再生有机碳资源,经催化转化可制备重要的含氧有机小分子化合物,作为传统化石资源路线的部分替代和补充。但我国利用生物质作原料的化工产业体系整体上还处于研发阶段,传统催化转化技术难以直接用于分子中C—O键为主的生物质高效转化。

元素化合物知识的复习

历年升学试题都以元素化合物知识为基点,形成一个以性质为核心的几方面知识相结合的试题结构,那么,如何指导学生复习元素化合物知识呢? 一、分析各类题型变换的本质,强化性质的记忆。元素化合物知识多、杂、乱,题型变化大。我将有关检查元素化合物知识的习题进行分类.如对转化制备类习题大致可分为: 1.由一种物质直接制取另一种物质。例:HCl+（）→（）+FeCl3或HCl→FeCl3重点是检查盐酸的性质. 2.完成下列各步转化。例:Mg→MgO→MgCl2重点检查镁和氧化镁的性质. 3.限定用某几种物质制取另一种物质.例:用铜、空气、盐酸、氢氧化钠溶液制取氢氧化铜.

Facile Preparation of Danazol Nanoparticles by High-Gravity Anti-solvent Precipitation （HGAP） Method

The nanoparticles of the hydrophobic drug of danazol with narrow size distribution are facilely prepared by controlled high-gravity anti-solvent precipitation （HGAP） process. Intensified micromixing and uniform nucleation environment are created by the high-gravity equipment （rotating packed bed） in carrying out the anti-solvent precipitation process to produce nanoparticles. The average particle size decreases from 55 μm of the raw danazol to 190 nm of the nanoparticles. The Brunauer-Emmett-Teller （BET） surface area sharply increases from 0.66 m^2·g^-1 to 15.08 m^2·g^-l. Accordingly, the dissolution rate is greatly improved. The molecular state, chemical composition, and crystal form of the danazol nanoparticles remains unchanged after processing according to Fourier transform infrared （FTIR） and X-ray diffraction （XRD）, The high recovery ratio and continuous production capacity are highly appreciated in industry. Therefore, the HGAP method might offer a general and facile platform for mass production of hydrophobic pharmaceutical danazol particles in nanometer range.

Preparation of 6-APA by Enzymatic Bioconversion in an Emulsion Liquid Membrane Reactor

Production of 6-aminopenicillanic acid (6-APA) by hydrolysis using penicillin acylase (PA) was studied as a model of an enzymatic emulsion liquid membrane (ELM) process. The loss of PA activity was examined for various membrane compositions (organic solvent, surfactant, carrier). The effects of some experimental variables on the stability of emulsion were investigated. It was found that the choice of organic solvent greatly affected the stability of the emulsion. Increasing the concentration of the carrier in the membrane phase increases the transfer rate of substrate and products but also has a destabilizing effect on the emulsion. The recovery of 6-APA obtained by a di-carrier system (N263-N1923) was much higher than those when either of the di-carriers was used separately. The whole process was controlled both by the enzymatic reaction rate and by the transfer rate of the substrate and the products, however, the ratio of them could be changed by varying the composition of the system. For an optimum condition, it was obtained that the recovery ratio of 6-APA was over 80% and the conversion of benzyl penicillin (PG) was up to 90% in the external phase after 30 minutes. Meanwhile, the breakage percentage of the emulsion was less than 2%.

Conversion of n-Pentanol and n-Butanol over Cu/AC Catalyst

It is already well known that availability of petroleum oil, as a world energy source, is running low. Much work has been done by experts to produce renewable energy, especially using vegetable oil as a raw material. Accordingly, this paper presents preparation and activity test of Cu catalyst using coconut shell activated carbon （AC） as a support, for conversion of n-pentanol and n-butanol to their alkenes as the first step of conversion of ethanol to biogasoline. This conversion is interesting due to any agriculture product containing sugar or starch can be converted to ethanol. Activated carbon was used as a catalyst support because this material is inert; hence, it would not yield unexpected side product, and pollution of environment with the used catalyst can be prevented because the used catalytic metal can easily be recovered. Results of the work showed that coconut shell carbon contained some metals, which disturbed in preparation catalyst by cation exchange process. Washing the carbon with ammonium acetate or HCI solution could reduce the metals content more compared to using water, with optimum concentration for ammonium acetate solution was 1.25 M. Application of Cu/AC in converting n-pentanol and n-butanol, based on qualitative analysis to the products using GLC, GC-MS, and FTIR, when n-pentanol and nitrogen gas were flowed into a reactor filled with Cu/AC catalyst, it could be converted to n-pentene with 200 ℃ as the optimal temperature. While when n-butanol and nitrogen gas were flowed into a reactor filled with more Cu/AC catalyst, the product was supposed to contain its aldehyde and butyl vinyl ether.

Microwave Preparation of SiO2-B2O3-Na2O-K2O-CaO-Fe2O3-TiO2 Glass System

This study reports preparation of glass composition （54.50 wt.%） SiO2, （10.80 wt.%） B2O3, （14.20 wt.%） Na2O, （1.20 wt.%） K2O, （6.00 wt.%） CaO, （4.00 wt.%） Fe2O3 and （9.30 wt.%） TiO2 by melt quenching method using direct microwave heating and conventional resistive heating. Study of dielectric loss factor of the glass as function of temperature illustrated increasing loss factor above 370 ℃, 550 ℃, 650 ℃ and 900 ℃, indicating enhanced microwave absorption by the glass at above these temperatures. Chemical analysis results of both the glasses depicted more volatilization loss of volatile ingredients in conventional heating. The study of chemical durability was performed from leachate analysis describing less leaching of Na2O, K2O and other constituents from glass melted in microwave furnace. Glass transition temperatures （Tg） were found to be 576.3 ℃ and 569.5 ℃ for glass melted in conventional and microwave heating route, respectively. Laboratory experiment of glass melting utilizing microwave energy as an alternate heating source demonstrated 70%-75% electrical power saving.

Hydrogenation Conversion of Phenanthrene over Dispersed Mo-based Catalysts

With oil-soluble molybdenum compound and sublimed sulfur serving as raw materials, two dispersed Mo-based catalysts were prepared, characterized and then applied to the hydrogenation conversion of phenanthrene. The test results showed that under the conditions specified by this study, the catalyst prepared in a higher sulfiding atmosphere was more catalytically active due to its higher content of MoS2 and stronger intrinsic catalytic activity of MoS2 unit, which demonstrated that the sulfiding atmosphere for the preparation of catalysts not only could influence the yield of MoS2 but also the structure of MoS2.The analysis on the selectivity of octahydrophenanthrene isomers revealed that the catalyst prepared in a lower sulfiding atmosphere had a relatively higher catalytic selectivity to the hydrogenation of outer aromatic ring and the structure of catalysts could be modified under the specific reaction conditions. Moreover, the selectivity between the isomers of as-octahydrophenanthrene at different reaction time and temperature was analyzed and, based on the results, a hydrogenation mechanism over dispersed Mo-based catalysts was suggested, with monatomic hydrogen transfer and catalytic surface desorption of the half-addition intermediates functioning as the key points. In addition, it is concluded that the catalyst prepared in a lower sulfiding atmosphere was more capable of adsorption than the other one.

Preparation High-Temperature Behavior of Conversion Coating of Alumina Film on FeCrAI （Ce） Stainless Steel

FeCrAI （Ce） stainless steel was functionalized by a conversion treatment in order to allow alumina by diffusion coatings with strong interfacial bonding. The very porous conversion coating produced in a pack aluminization technique had excellent adhesion and was conductive enough to permit conditions favorable for the precipitation of alumina oxyhydroxide during aluminum diffusion coatings. In this work, the bed was prepared as a mixture of A1, NH4C1 and A1203. In the high-activity bed were heat-treated at 1,173 K in an atmosphere made up of team with subsequent air-cooling. The effect of the bed content on the coating was examined. With the high-activity, the desired Fe2Al5 was formed as the outermost coating layer. The coating presented chemical composition gradients suitable for strong adhesion. The improvement of the thermal oxidation behaviour was studied at 1,373 K. Two different aqueous environments, which are （1） NaC1 and （2） H2SO4, are employed for using the technique of potentiodynamic polarization curve. The obtained experimental electrochemical parameters （Ecorr, Jcorr etc,） were used to compare the corrosion resistance of the tested steel state complemented by MEB （electronic scanning microscopy） in combination with dispersive analysis X in energy （EDS） or X ray diffraction indicated that the elements concentration maximum was located in the vicinity of the interface especially in the FeCrAI （Ce） coated by spherical A1203 powder. These results an discussed in terms of an addition effect on the development of the microstructure of oxide films.

Recent advances in heterogeneous catalytic conversion of glucose to 5-hydroxymethylfurfural via green routes

With concerns of diminishing fossil fuel reserves and environmental deterioration, great efforts have been made to explore novel approaches of efficiently utilizing bio-renewable feedstocks to produce chemicals and fuels. 5-Hydroxymethylfurfural(HMF),generated from dehydration of six-carbon ketose, is regarded as a primary and versatile renewable building block to realize the goal of production of these high valued products from renewable biomass resources transformation. In this review, we summarize the recent advances via green routes in the heterogeneous reaction system for the catalytic production of HMF from glucose conversion, and emphasize reaction pathways of these reaction approaches based on the fundamental mechanistic chemistry as well as highlight the challenges(such as separation and purification of products, reusing and regeneration of catalyst, recycling solvent) in this field.

Facile preparation of organometallic perovskite films and high-efficiency solar cells using solid-state chemistry

The power conversion efficiency of organometallic perovskite-based solar cells has skyrocketed in recent years. Intensive efforts have been made to prepare high-quality perovskite films tailored to various device configurations. Planar heterojunction devices have achieved record efficiencies; however, the preparation of perovskite films for planar junction devices requires the use of expensive vacuum facilities and/or the fine control of experimental conditions. Here, we demonstrate a facile preparation of perovskite films using solid-state chemistry. Solid-state precursor thin films of CHBNH3I and PbI2 are brought into contact with each other and allowed to react via thermally accelerated diffusion. The resulting perovskite film displays good optical absorption and a smooth morphology. Solar cells based on these films show an average efficiency of 8.7% and a maximum efficiency of 10%. The solid-state synthesis of organometallic perovskite can also be carried out on flexible plastic substrates. Using this method on a PET/ITO substrate produces devices with an efficiency of 3.2%. Unlike existing synthetic methods for organometallic perovskite films, the solid-state reaction method does not require the use of orthogonal solvents or careful adjustment of reaction conditions, and thus shows good potential for mass production in the future.