煤与稻杆共液化性能研究

通过与神府煤和稻杆单独热解和液化的对比,研究了神府煤与生物质稻杆的共热解和共液化行为,考察和揭示了两者之间的协同作用。热重分析表明,稻杆的热解温度较低,在与神府煤共热解时,由于在较低温度下稻杆热解形成的自由基对煤热解的促进作用,使得混合物实际的热解失重高于对应的加权平均计算结果。共液化结果表明,神府煤与稻杆之间存在着明显的协同效应,并因液化反应条件的不同而不同。在较高的液化反应温度和较长的反应时间,由于煤本身的热解速率增加,系统内供氢能力的不足导致逆向缩合反应速率增加,减弱了两者的协同效应。在实验条件范围内,当稻杆配入量为50%,在400℃,60min的反应条件下,神府煤与稻杆共液化时产生的协同效应最大。此时,共液化转化率和正己烷可溶物分别高于对应加权平均计算值的14.8%和9.7%,气体产率也同时降低了2.6%。     

煤液化油催化加氢精制的研究

煤液化油的催化加氢脱杂原子反应受多种因素影响,其中反应条件的影响较大。反应条件不但影响反应的脱硫率、脱氮率、产物的H/C 原子比、气体产率等,还与催化剂积炭率有密切关系。在煤液化油加氢反应中,催化剂表面积炭是导致催化剂失活的主要因素。对催化剂积炭量研究的很多,但很少报道积炭量随反应条件的变化规律。选择合适条件进行煤液化油催化加氢,是煤液化工程技术上的一个     

复杂多相体系煤加氢液化反应与氢传递的研究

研究新疆淖毛湖煤(NMH)在四氢萘为溶剂条件下的加氢液化反应行为,探究了液化过程氢传递规律,并借助XRD、饱和磁化强度和扫描电镜表征手段,研究了煤液化条件下铁系催化剂的相态变化对煤液化性能的影响。结果表明,NMH煤在420℃、17 MPa就具有良好的液化效果;催化剂的活性态Fe7S8在煤液化反应初期发挥了催化作用,加氢液化后期,转变为非活性态Fe_9S_(10)和FeS;提高催化剂加氢活性并延长反应时间有利于沥青烯和前沥青烯加氢轻质化;催化剂有利于活化气相氢向煤的热解产物和溶剂转移,也有利于活化溶剂中的氢向煤的热解产物转移;溶剂对液化反应的活性氢贡献更大,约为气相氢的两倍,气相氢向溶剂传递的氢量随温度的升高、压力的增大和时间的延长变化不大,气相氢和供氢溶剂供氢与煤和沥青质向油气转化呈正相关。     

将穆斯堡尔谱应用于煤炭催化液化的研究——Ⅱ.某些变数对铁催化剂转化的影响

在以铁系物为煤液化催化剂的反应中,新生Fe_(1-x)是催化活性物种。Monta no认为煤液化条件下,FeS_2向Fe_(1-x)S转化的过程依赖于反应时间、温度和液化煤种。随着液化反应时间的增长,温度的提高,FeS_2转化率增大。液化反应体系的H_2S气体分压影响着Fe_(1-x)S的化学计量式。本文用穆斯堡尔谱研究了煤在铁系催化液化反应中,几种因素对Fe_(1-x)S生成情况的影响。     

不同醇类对磷钨酸催化超临界醇解液化木屑的影响

以可溶解于醇类的磷钨酸为催化剂,在超临界醇体系下液化木屑,探讨甲醇、乙醇、正丙醇、异丙醇等不同醇类溶剂对木屑醇解液化的影响,同时采用FT-IR和GC-MS等对液化产物进行了表征分析。结果表明,反应压力和溶剂的极性大小对木屑的液化效率以及液化产物影响显著。甲醇、乙醇、正丙醇、异丙醇反应体系的液化率和主要液化产物酯类化合物的含量比率,分别为54.75%和43.759%、90.29%和23.531%、85.90%和41.761%、89.15%和28.619%,特别在甲醇体系中,乙酰丙酸甲酯的含量高达33.374%;在异丙醇体系中酚类化合物可达到24.342%;醛类化合物只出现在甲醇体系中。在正丙醇体系中没有酚类产物,表明极性最小的正丙醇,提供很少的H*,更不容易将木质素降解。     

超临界水中煤与聚苯乙烯的共液化研究

在间歇式高压反应装置中,研究了兖州烟煤与塑料聚苯乙烯(PS)在超临界水中的共液化,考察了水/物料比(质量比10～30)、反应温度(360℃～430℃)和塑料添加量(10%～40%)对煤液化转化率及产物收率的影响.结果表明,随着水/物料比的增加,煤液化转化率先升高,之后变化不大;油气产率则呈上升的趋势.反应温度高于420...     

TG-FTIR研究煤油共热解产物逸出行为

煤油共液化过程中煤与重油先发生共热解,而后加氢转化为小分子产品。因此,阐明重油对煤热解逸出产物的影响规律是调控共液化产物组成的重要热化学基础。本研究采用TG-FTIR对比研究塔河渣油(AR)和淖毛湖煤(NMH)单独热解及其共热解过程,结合热解活化能计算,探索共热解过程中塔河渣油(AR)对淖毛湖煤(NMH)热解产物逸出产物的影响。结果表明,单独热解时AR先于NMH发生热解反应。两者1∶1(质量比)混合共热解时,相比于单独热解计算的理论值,最大失重峰温度前移7℃,失重率增加约3%,共热解平均活化能降低23.6 kJ/mol,表明AR率先热解会诱发NMH热解,降低热解反应能垒。TG-FTIR结果显示,AR产生的烷烃类自由基会与NMH热解产生的含氧自由基结合,形成醇、醚等烷基类含氧有机化合物,从而抑制煤中羧基转化为CO₂的过程。研究结果有助于揭示共液化反应过程中重油对煤液化产物组成的影响。     

杨村烟煤与石油渣油共处理反应特性的研究

用共振搅拌反应器研究了山东兖州杨村的烟煤与北京燕山石化公司的石油渣油共处理液化的反应过程，考察了反应温度和反应时间对煤液化转化率及产物中前涸青烯，苯可溶组分的影响。     

煤与废塑料共液化中氢转移的示踪试验研究 Ⅱ．富氢塑料中的氢转移

采用放射性同位素3H标记的聚乙烯塑料进行了先锋褐煤与低密度聚乙烯（LDPE）的共液化示踪试验，并考察了钼灰（FAMo）催化剂和不同溶剂的影响，示踪试验结果表明，在先锋煤与LDPE共液化过程中，富氢塑料LDPE中的含氢基团确实起着供氢作用，而且这种含氢基团向煤液化自由基的氢转移无需经过供氢溶剂进行传递，钼灰催化剂能够加速LDPE塑料的供氢作用，使用非供氢溶剂时，在煤与LDPE共液化反应初期，LDPE中的含氢基团在钼灰催化剂作用下较易向煤热裂解产物转移，并出现供氢竞争现象。     

高温高压下煤液化油气液平衡体系的研究

煤液化过程中,反应单元和分离单元是整个液化体系的核心部分,反应器和分离器中各组分在气、液相中的平衡组成确定不仅决定设备的尺寸设计,而且对液化过程中供氢溶剂的选择和反应条件的优化起到关键作用。但由于煤液化油在高温高压下的气、液平衡数据不足,使得反应器内的组成分布无法预测,相关的反应器设计过程仅能凭经验进行。为得到反应条件下的气液平衡数据,研究引入流程模拟软件Aspen Plus,将煤液化油蒸馏得到的窄馏分段与各种气体组分（如H₂、C₂H₆等）共同建立了煤液化油闪蒸过程,得到了高温高压下煤液化油气液平衡体系。利用闪蒸体系计算得到在给定温度、压力情况下,各组分在高温、低温分离器内的气、液两相分布情况,通过改变高温分离器的温度和压力,分析了高温分离器内相平衡常数随温度（623.15K~723.15K）、压力（10MPa~21MPa）变化的规律。为进一步归纳适用于煤液化油的气液平衡方程,以高温分离器数据为基础,对推导建立的高压下烃类相平衡方程中的参数进行回归,得到高温高压下,适用于神华煤液化油并具有物理意义的二元（T,p）气液相平衡常数方程。     

A carbanion induced synthesis of highly congested pyrazole and imidazole containing heterocycles

An efficient approach to the synthesis of highly congested di, penta and hexacyclic pyrazoles as well as imidazole fragment containing novel heterocyclic molecule has been developed through a carbanion induced transformation of suitably functionalized 2H-pyran-2-ones, benzo[h]chromene and thiochromeno[4,3-b]pyrans. Due to the presence of fluorescence, we report their prime application metal sensor as off/on switching in ferric ions.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Selective synthesis of 4,5-dihydroimidazo- and imidazo[1,5-a]quinoxalines via modified Pictet–Spengler reaction

An efficient tandem approach for the selective synthesis of 4,5-dihydroimidazo[1,5-a]quinoxalines 6a–g and imidazo[1,5-a]quinoxalines 7a–h by the reaction of 2-imidazolyl anilines 4a–c with aryl aldehydes 5a–k under mild reaction conditions is described. Introduction of electron releasing alkyl groups in substrates 4a–b was found to be instrumental for the success of the reaction.     

Understanding the Diels-Alder reactivity of 1,2-azaborine analogues

The Diels-Alder reactivity of 1,2-heteroborines (H₄C₄B(H)X, X?=?NH, PH, AsH; O, S, Se) has been computationally explored by means of Density Functional Theory (DFT) calculations. The influence of the HB?=?X fragment on the reactivity of the system has been quantitatively analyzed in detail by means of the so-called Activation Strain Model (ASM) of reactivity. It is found that the interaction between these species and the dienophile is significantly stronger than that computed for their all-carbon isoelectronic counterpart, benzene. In addition, the strain energy plays a key role in the observed reactivity trends. The role of the aromaticity strength of these heteroarenes on the reactivity is also assessed.     

Synthesis of N-substituted carbazolones from α-iodo enaminones via Pd(0)-catalyzed intramolecular coupling under microwave irradiation

A variety of N-aryl and N-alkyl carbazolones were conveniently achieved in good to high yields via Pd₂(dba)₃-mediated intramolecular coupling of N-substituted α-iodo enaminones under microwave irradiation. The Pd(0)-catalyzed cyclization was found to proceed favorably with the more electron-deficient phenyl ring during the reactions involving unsymmetrical N,N-diaryl α-iodo enaminones. This unique property enables the construction of carbazolone skeleton containing nitro substituted benzenoid ring.     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles by intramolecular nitrilimine cycloaddition

Both substituted 2,4,5,6-tetrahydrocyclopenta[c]pyrazoles and 2,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles have been synthesized by the 3+2 intramolecular dipolar cycloaddition of nitrilimines to alkynes. This cyclization has been extended to more versatile 3-bromo derivatives by the use of alkynylbromides as dipolarophiles.