铜锰高温煤气脱硫剂的研究：Ⅰ.脱硫工艺条件对脱硫剂性能的影响

用共沉淀法制得的铜锰脱硫剂是一种新型的高温煤气脱硫剂。本文从硫化氢浓度，脱硫温度，空速和脱硫剂的粒度几个方面考察了地脱硫剂的影响，可以看出该脱硫剂的反应活性与硫化氢浓度基本上成正比，但与脱硫温度的关系较为复杂。在低于６００℃时脱硫剂的活性基本上随温度升高而增加，而在６００℃以上的温度时则有所波动。空速对其反应活性的影响类似于硫化氢浓度的影响。     

高温煤气铁钙基脱硫剂再生研究

在固定床装置上考察了温度和氧浓度对铁钙基脱硫剂再生率以及二次脱硫活性的影响，同时还考察了此脱硫剂用于模拟的脱硫除尘一体化条件下，黏附于表面的粉尘对脱硫剂再生行为以及二次脱硫行为的影响。结果表明，该脱硫剂在480 ℃下再生效果良好，650℃再生率下降，在考察的温度区间内（400 ℃～650 ℃）温度对二次脱硫活性影响较小，在以后的循环中，温度对再生率以及脱硫活性的影响也小，再生气氛中氧浓度对再生率以及二次脱硫活性的影响不明显；研究发现加入粉尘虽然会降低脱硫剂的再生率，但基本不影响二次脱硫活性。     

浸渍活性炭脱除低质量浓度H2S性能的研究

浸渍法制备了Na2CO3浸渍活性炭（IACⅠ）和一种高效脱硫剂（IACⅡ）。通过测定低质量浓度H2S在固定床上的穿透曲线，比较了原活性炭（AC）、IACⅠ和IACⅡ的脱硫效果。考察了原料气相对湿度，H2S质量浓度对穿透过程的影响。建立了固定床反应器一维轴向扩散模型模拟脱硫穿透曲线，并进行了数值求解。通过模型计算与实验测量穿透曲线拟合，确定了有效扩散系数等参数。结果表明，IACⅡ的脱硫效果最佳，其有效扩散系数较IACⅠ有所提高。提高相对湿度有利于增大硫容，但有效扩散系数略有降低。随着H2S入口质量浓度升高，有效扩散系数增大，穿透变快，硫容略有降低。     

硬脂酸前驱体法制铁酸锌脱硫剂及其在中温下的应用

以硬脂酸为凝胶剂，经由溶胶、凝胶、煅烧等步骤直接合成了晶体尺寸为纳米级(15nm～32nm)的铁酸锌脱硫剂，并应用TG-DTA、XRD、BET等测试手段对干凝胶及所得产品进行分析表征。结果表明，硬脂酸前驱体法合成温度低，操作简便。随着煅烧温度的升高，产品的比表面积减小，平均粒径增大，脱硫性能变差；该法制备的脱硫剂在350℃~550℃活性高，脱硫精度高，硫容大，而且再生性能良好，450℃下完全再生。     

新型Mn-Fe/Al_2O_3高温脱除H_2S的实验研究(Ⅱ)

本文首先研究了粒度dp=07mm脱硫剂的脱硫反应和再生反应性能。研究表明当Mn∶Fe=2∶1(w)、载体在1000℃焙烧后,脱硫剂有较好的脱硫反应性能,其最佳的脱硫反应温度为550℃,且在710℃、O2浓度低于1083%(v)、空速2000～3000h-1再生条件下,可完全对脱硫剂进行再生;H2S浓度影响脱硫剂的初始脱硫反应速率和穿透反应时间,但对脱硫剂的脱除率和穿透硫容影响不大。并研究了粒度dp=3mm脱硫剂的脱硫情况。实验结果表明,小颗粒脱硫剂的脱硫反应主要为化学反应控制,大颗粒脱硫剂主要为扩散控制。为此对大颗粒脱硫剂进行了工程设计,即采用活性组分非均布脱硫剂。研究表明,非均布脱硫剂明显提高了脱硫剂的平均脱硫反应速率和硫容,同均布脱硫剂相比,非均布脱硫剂再生后具有较好的脱硫稳定性能。     

多周期脱硫/再生对脱硫剂Ce-Fe/ZnO表面结构及再生性能影响

通过透射电子显微镜(TEM), X射线衍射(XRD), X射线光电子能谱(XPS)等技术对多周期脱硫/再生后CFZ脱硫剂微观结构进行了表征, 分析脱硫剂经多周期脱硫/再生结构发生的变化, 从微观结构角度探讨脱硫剂结构的变化对脱硫性能的影响. 结果表明, 第一次再生后脱硫剂的形貌和粒径变化不大, 比表面积减小66.8%, 孔分布发生较大变化, 较大和较小孔径明显减少, 10～50 nm孔所占比例增加44.6%, 再生过程产生硫酸盐|2～5次再生后脱硫剂的结构变化不大, 脱硫性能趋于稳定, 表明脱硫剂结构和再生过程产生的硫酸盐对脱硫剂表面的覆盖是影响脱硫性能的主要因素|经5次再生, 6次脱硫的累计硫容为12.8%, 是新鲜脱硫剂1次脱硫硫容的5.56倍.     

蜂窝状堇青石基CuO/Al2O3催化剂用于烟气同时脱硫脱硝的研究

考察了制备参数及反应条件对蜂窝状堇青石基CuO/Al2O3催化剂同时脱硫脱硝活性的影响。结果表明，添加碱金属可以提高脱硫活性, 但由于促进NH3氧化而降低了脱硝活性。为了获得理想的同时脱硫脱硝活性，催化剂的适宜载铜量为6.0％，载钠量为2.0％。随着反应温度从350 ℃升高到450 ℃，该催化剂的脱硫活性逐渐升高，再生后脱硫活性都有所下降，但仍具有活性随温度升高而升高的趋势，说明脱硫过程为反应控制型；但由于温度升高，NH3氧化加剧，脱硝活性逐渐降低，所以适宜操作温度为400 ℃。在1 450 h－1～3600 h－1范围内， 空速对脱硝活性影响不大， 对脱硫活性影响较大。 对于再生催化剂，当空速由3 600 h－1降低到2 300 h－1时，硫容（SO2转化率达80％时单位质量催化剂所吸附的SO2量）不断增加，继续降低空速时硫容基本保持不变，所以适宜操作空速为2 300 h－1以下。     

新型M—Fe／Al2O3高温脱除H2S的实验研究（Ⅱ）

本文首先研究了粒度ｄｐ＝０．７ｍ脱硫剂的脱硫反应和再生反应性能。研究表明当Ｍｎ：Ｆｅ＝２：１（ｗ）,载体在１０００℃焙烧后,脱硫剂有较好的脱硫反应性能,其最佳的脱硫反应温度为５５０℃、且在７１０℃、Ｏ２浓度低于１０．８３％、空速２０００￣３０００ｈ＾－１再生条件下可完全对脱硫剂进行再生;Ｈ２Ｓ浓度影响脱硫剂的初始脱硫反应速率和穿透反应的时间,但对脱硫剂的脱除率和穿透硫容影响不大。并研究了粒度ｄｐ＝     

高温煤气脱硫 Ⅰ．铁锌基脱硫剂脱硫工艺条件及硫化动力学

用自制的铁酸锌高温煤气脱硫剂研究了硫化氢浓度、硫化温度、空速对脱硫反应及脱硫剂物理性质的影响。结果表明：铁酸锌脱硫剂的反应活性随着Ｈ２Ｓ浓度及硫化温度的升高而升高，脱硫温度为５５０℃时，脱硫剂的硫容量最高，脱硫剂的物理性质基本保持不变；硫化空速为８５０ｈ￣（－１）时，空速和反应时间同时达到最大值。硫化反应可用未反应核收缩模型描述，得到了转化率与时间之间的动力学方程。     

活性炭（焦）低温吸附催化脱除H2S的基础研究

以活性炭、活性焦作为脱硫剂,并应用BET、XPS等测试手段对其进行分析表征。结果表明,活性炭（焦）的脱硫能力与其表面酸碱性有着密切的关系,增加表面上起碱性作用的π-π^﹡键,羰基官能团（C-O和醚基官能团（C-O）的浓度,可增加其表面催化作用,特别是C-O官能团;反应温度对活性炭（焦）的脱硫性能有很大的影响,脱硫剂在150℃～180℃活性高,硫容大,副反应少;水蒸气对活性炭（焦）脱除H₂S有促进作用。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

KMnO₄-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

Regiospecific and direct imidation of the methyl C(sp³)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.