石油焦系活性炭的吸附脱硫

选取独山子石油焦为原料，以物理活化法制得比表面积达500m2/g～900m2/g的活性炭，进行吸附脱硫研究。采用酸氧化法对活性炭孔结构和微观孔径分布进行改性。酸氧化使活性炭表面酸性官能团含量明显增加，增加量约为原来的5倍。活性炭吸附脱硫性能随表面酸性官能团含量的增加而增大。理想的酸化条件是浓硝酸120℃氧化40min。通过静态吸附实验，活性炭吸附脱硫的最佳条件是，温度25℃，压力1.0MPa，静态吸附6h。最佳条件下吸附脱硫可使模型化合物硫的质量分数从137.9×10－6降至3.1×10－6。从活性炭孔径匹配考察可知，平均孔直径在0.8nm～2.1nm的活性炭对模型化合物硫的质量分数降低具有明显效果。     

活性炭吸附脱除水中抗生素污染物研究进展

活性炭对抗生素污染物吸附性能的主要影响因素是其孔结构和化学结构性质。活性炭孔结构的构建方法可分为活化法、模板法和原位法,化学结构性质的调控方法可分为后处理法和原位法,掺杂的元素有氧、氮、硫、磷、硼等。围绕抗生素污染物的吸附,综述了活性炭的性质调控方法,并展望了活性炭性质调控的发展方向,为新型高效活性炭吸附剂的构建及吸附机理的研究提供了指导与借鉴。     

活性炭孔隙结构对催化氧化脱除单质汞的影响

研究活性炭在硫化氢存在条件下催化氧化脱除煤气中单质汞的吸附机理和探讨提高其吸附能力的方法,在模拟煤气气氛下对3种活性炭和一种活性焦进行汞的吸附性能实验,并进一步分析活性炭(焦)的孔隙结构。用BET方程处理N₂等温吸附数据,计算比表面积;用HK法进行微孔分析;用BJH法计算中孔孔径分布。结果表明,硫化氢被催化氧化后,生成吸附在活性炭孔壁上的活性硫促进了对汞的吸附;随着活性炭微孔和中孔体积的增大,活性炭对汞的吸附能力得到提高。     

金离子的活性炭吸附及微波解吸

金离子的活性炭吸附及微波解吸杨春芬，王光灿（云南大学化学系实验中心昆明６５００９１）关键词金，硫脲，吸附，微波解吸用硫脲浸出法提取金、银具有速度快、毒性小，再生净化工序简单等优点￣［１］．用活性炭自硫腺浸金溶液中吸附金是极为有效的方法，但吸附后不易洗...     

活性炭的改性及对Pb2+的动力学吸附研究

论文以活性炭为主体吸附剂，进行氯化铁改性，制备出氯化铁改性活性炭吸附剂，并通过FT-IR、SEM、比表面积和孔体积进行表征。实验进一步探究改性活性炭对Pb²⁺的吸附能力，结果表明，当吸附时间为300 min,吸附剂投加量为0.4 g, pH为6时，吸附效果最佳。在此吸附条件下，改性活性炭对Pb²⁺的去除率达到91.2%。对改性活性炭吸附Pb²⁺进行动力学吸附研究，结果表明二级速率方程能够更好地描述其动力学吸附过程，吸附的机理可归结为氯化铁改性导致活性炭孔道结构中酸性官能团增加，使得金属阳离子与官能团上的H之间产生离子交换作用，有利于吸附的进行，这一实验结果为后期循环吸附研究提供了新依据。     

活性炭及甲酸催化过氧化氢氧化噻吩脱硫研究

以噻吩代表汽油中的有机硫化合物，将其溶解于正辛烷配制成反应原料，考察了活性炭对噻吩的吸附脱硫情况，研究了质量分数为30％的过氧化氢水溶液为氧化剂，在活性炭和甲酸的催化作用下，反应原料中噻吩氧化脱硫。考察了活性炭的催化性能及反应条件对其催化性能的影响。实验结果表明，30％H2O2-HCOOH-AC（活性炭）三元体系产生的过氧甲酸和羟基自由基能将模型有机硫化合物氧化，噻吩的氧化脱硫率可达到85％以上；活性炭和甲酸的催化氧化性能明显优于单纯使用甲酸催化性能。甲酸浓度、活性炭加入量、过氧化氢初始浓度及温度对噻吩硫的氧化脱除均有影响。     

板栗壳活性炭对重金属离子吸附性能研究

研究了不同制备条件下,板栗壳活性炭对重金属离子Cu2+和Cd2+的静态吸附性能。以板栗壳为原料,采用ZnCl2活化法制备活性炭,使用X-射线衍射、扫描电镜、氮气吸附等方法对活性炭进行表征;比较了活性炭内部结构对Cu2+和Cd2+的吸附性能影响;同时考察了吸附温度、溶液pH值等对Cd2+和Cu2+的吸附性能的影响。研究结果表明:板栗壳制备活性炭最佳条件为ZnCl2活化浓度30wt%,料液比1:6,炭化温度600℃,炭化时间3h;同时发现板栗壳活性炭是一种具有较多孔隙的无定型炭材料,所制备的活性炭平均孔径为2~6nm,孔容为0.04~0.14cm3/g,比表面积可以达到1500m2/g以上;板栗壳活性炭对重金属离子的吸附性能主要由本身的比表面积和孔容大小决定,且同时受吸附温度和溶液pH值的影响,上述条件制备的活性炭吸附Cu2+的最佳条件为温度25℃,溶液pH值为6.5;吸附Cd2+的最佳条件为温度25℃,溶液pH值为7.5。     

硫化氢对活性炭脱除单质汞的影响

H₂S是煤气中的含硫成分,活性炭能否催化氧化煤气中的H₂S形成活性硫,以促进H₂S和Hg⁰的协同脱除是值得研究的。 本文首先通过程序升温脱附和热力学分析了低温情况下H₂S对活性炭脱除Hg⁰的影响。 在较低吸附温度130 ℃下,H₂S不仅不能作为硫源,还使活性炭对Hg⁰的吸附显著减弱,这主要是由于H₂S对活性炭表面的吸附氧的消耗以及H₂S对含氧官能团的氧的取代反应造成的。 在此基础上,进一步研究了高温下H₂S对活性炭的影响,高温也不能使活性炭有效渗入单质硫。 所以无论低温还是高温情况下,利用H₂S作为硫源使Hg⁰以HgS的形式脱除并不是活性炭脱汞的可行手段。 本文揭示了较宽的温度范围内H₂S对单纯的活性炭脱除Hg⁰的影响机理,能为用于煤气脱汞的活性炭的设计以及作为负载时机理研究提供支持作用。     

活性碳纤维的结构修饰及其吸附氙性能的研究

活性炭纤维对氙的吸附容量与其孔结构密切相关，为了提高活性炭纤维对氙气的吸附容量，本文分别用亚甲基蓝、对硝基苯酚等有机物，或氯化钠、碘等无机化合物填充的方法修饰活性炭纤维的孔结构；以及利用高锰酸钾或硝酸等氧化处理修饰活性炭纤维的表面化学性质，同时，利用低温氮等温吸附表征了这些改性活性炭纤维的孔结构，以及通过光电子能谱表征了改性活性炭纤维的表面化学结构，上述化合物充填或氧化改性活性炭纤维对氙的吸附性能的研究结果表明，适量化合物填充，或合适浓度硝酸对活性炭纤维的表面处理，可以有效地修饰活性炭纤维的孔结构或改变活性炭纤维表面对氙的亲和力。因而可有效地提高改性活性炭纤维对氙的吸附容量。     

甲烷在特制活性炭上吸附性能

用不同的原料制得了多种高比表面的活性炭吸附剂．用标准容积法测得高压下（０～５０ＭＰａ）不同活性炭对甲烷的吸脱附等温线,得到了吸附容量和有效吸附容量．研究了温度对吸附等温线的影响．利用ＣｌａｕｓｉｕｓＣｌａｐｅｙｒｏｎ方程解析了甲烷在活性炭上的等量吸附热．结果表明,活性炭对甲烷的吸脱附存在着滞后现象,活性炭的比表面和堆密度是活性炭吸附性能的主要指标,找到了最佳甲烷吸附剂．     

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%).     

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 pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.