金属柱撑黏土催化非均相Fenton技术的研究

金属柱撑黏土(PILC)能够在保证Fenton法对有机污染物的去除功效的同时,较好地克服Fenton法催化剂易流失、适用pH范围小等缺点.介绍了金属柱撑黏土制备的新进展,总结了柱撑黏土单独催化或与紫外等技术联合催化非均相Fenton反应降解水体有机污染物的研究成果,分析了柱撑黏土催化非均相Fenton反应的机理.针对目前研究仍然存在的问题,结合实际应用的需求,提出了今后工作中一些值得关注的方向.     

多孔碳柱撑膨润土的制备与表征

用十六烷基三甲基溴化铵和苄基三甲基氯化铵改性膨润土制备了多孔碳柱撑膨润土.用Fourier变换红外光谱仪、扫描电子显微镜和氮气吸附-脱附、热分析系统地研究了有机改性剂对多孔材料性能的影响.结果表明:膨润土微粒与有机改性剂以共价键和离子嵌入2种形式结合;多孔碳柱撑膨润土的微观形貌呈针片状,最可几孔径分布大约在1.7nm;多孔材料的主要结构是由碳化的大粒子柱撑而构建的二维孔径,烧结后的有机黏土热稳定性大大提高.     

蒙脱石和高岭石吸附水溶液中重金属离子的实验研究

综述了近几年研究人员以蒙脱石、高岭石和膨润土作为吸附材料,去除水溶液中的砷、镉、铬、铜、铅几种重金属离子。通过酸性活化改性,有机分子嫁接改性,纳米氧化物涂层和柱撑等手段,提高了粘土矿物的吸附性能,达到更好的吸附效果。结果表明有机改性更有利于蒙脱石等粘土矿物对于重金属离子的吸附,同时指出pH是影响吸附效果的关键因素。     

黏土负载型类Fenton催化剂的研究进展

黏土负载型类Fenton催化剂是将活性金属固定在黏土上,用以催化活化H₂O₂产生羟基自由基去除难降解有机污染物,克服了均相Fenton氧化适用pH范围窄、易产生铁泥沉淀等缺点。本文从黏土的类型和结构特点出发,简述了层状与非层状黏土负载活性金属的特点及其催化性能;分析了柱撑、浸渍、沉积-沉淀等活性金属负载方法和黏土的改性手段;阐述了负载活性金属类型及其对催化性能的影响。针对黏土负载型类Fenton催化剂的特点和现阶段存在的问题,从黏土负载型催化剂的活性金属负载形式、负载方法和高效稳定催化性能的需求等角度指出了今后的研究方向。     

柱撑粘土合成柱化机理及应用研究进展

柱撑粘土是一种独特的二维类沸石材料,通常由大的水解无机金属阳离子与粘土层间的补偿阳离子电荷进行离子交换后在高温下脱水、脱羟基后制备而得。柱撑粘土由于其具有大的比表面积、孔容及层间距而被作为新型固体酸催化剂和吸附材料得到了越来越多的关注。概述了柱撑粘土的制备、柱化机理及作为石油催化材料和吸附功能材料的应用。     

Fe、Al柱撑膨润土对锌离子的吸附性能

制备了Fe、Al柱撑膨润土,研究了其对水溶液中锌离子的吸附去除性能,结果表明:Fe、Al柱撑膨润土对水溶液中的锌离子有很好的去除效果,当其用量为0.5 g时,水溶液中锌离子的吸附去除率达到93.6%;Fe、Al柱撑膨润土对水溶液中的锌离子的吸附在60 min达到平衡;溶液pH对水溶液中锌离子的去除有一定的影响,在中性和弱碱性条件下的去除率大于酸性。平衡吸附量与平衡质量浓度之间的关系符合Freundlich和Langmuir等温吸附方程所描述的规律。     

弱酸性蓝GR在羟基铁柱撑膨润土上的吸附研究

用无机大分子羟基铁离子对浙江天然膨润目进行柱撑,研究表明羟基铁子交换制得的柱撑膨润土具有很好的吸附能力（好于单纯钠有机化膨润土）;并研究了各测试条件的改变对弱酸性深蓝GR在改性膨润土的吸附去除率影响;测试了各种改性膨润土的等温吸附线。     

改性/新型氟吸附材料的研究进展

按照金属基吸附剂、炭基吸附剂、黏土矿物类吸附剂、高分子生物类吸附剂、工业副产物或废弃物、纳米材料、陶粒等吸附剂类型,全面综述了近些年来国内外在含氟水吸附处理中吸附材料的研究开发与应用现状。着重介绍了传统吸附材料的改性和一些新型吸附材料的合成、吸附性能和机理,并对今后氟吸附材料的发展方向进行了展望。     

柱撑膨润土吸附水中苯胺的性能研究

研究了无机、有机和无机-有机柱撑膨润土对水中苯胺的吸附去除性能,结果表明:3种柱撑膨润对苯胺的去除效果明显高于膨润土原土,当投土量为0.2 g时,对苯胺的吸附去除率分别为86.77%、96.38%、92.51%;3种柱撑膨润土对苯胺的吸附在60 min达到平衡;溶液pH值对苯胺的去除有一定的影响,在酸性条件下的去除率略大于中性和碱性;温度升高,苯胺的去除率略有下降.     

二氧化钛柱撑膨润土对染料甲基橙的吸附行为

以sol-gel法制备TiO2溶胶和钇掺杂TiO2溶胶为柱化剂,制备出了TiO2柱撑膨润土和钇掺杂TiO2柱撑膨润土.X射线衍射分析表明经柱撑后的膨润土层间距明显增大,达1.9 nm以上,经500℃煅烧后其层间距稳定在1.8 nm以上.研究了甲基橙在4种TiO2柱撑膨润土上的吸附行为,结果表明4种TiO2柱撑膨润土吸附染料甲基橙的速率和吸附量均较大,其吸附动力学行为均遵循Bangham方程和Langmuir方程所描述的规律.平衡吸附量qe与平衡浓度ρe之间的关系符合Freundlich和Langmuir等温吸附方程.其吸附均为吸热过程,吸附热值在12～17kJ/mol,吸附表现为表面物理吸附和离子交换作用.     

SOLID PHASE EXTRACTION FOR DETERMINING ORGANIC COMPOUNDS IN HIGH IONIC STRENGTH SOLUTIONS

ABSTRACT

Extraction techniques for semi-volatile organic compounds from caustic and high ionic strength solutions are presented. It is demonstrated that simple liquid-liquid extraction from a high ionic strength aqueous solution can allow inorganic ions to partition from the aqueous phase into the organic extraction phase. The ability of solid-phase extraction (SPE) adsorbents to separate organic target compounds from a sample, without significant carry-over of inorganic material, is compared to that of Liquid-liquid extraction. The most useful SPE media was a commercially available alumina substrate coated with a robust non-polar phase. Extractions of three compound classes, are presented: aromatic, alkyl hydrocarbons and alkyl phosphates. Extraction yields ranged from 42 to 97.6% (6-12% RSD). The range of yields for each chemical class was 7.5-79.9%, 14.3-68.3% and 91.1-97.6% for the aromatic, alkyl hydrocarbons and alkyl phosphate compounds respectively.     

可溶有机质介导硝基芳香化合物降解研究进展

大量研究表明, 可溶性有机质因自身的醌呼吸结构能够作为氧化还原体来催化转化多种有机和无机化合物, 然而其影响机制尚未完全了解, 因此需要更深层次的研究以阐明限制可溶性有机质介导化学和生物转化有机污染物的机理。本文以硝基芳香化合物为例, 全面阐述了其化学和生物降解机理以及可溶性有机质作为氧化还原电子穿梭体对其还原转化过程介导作用的研究进展;回顾了各种因素影响可溶性有机质催化转化硝基芳香化合物的效果, 并寻求氧化还原效率较高的可溶性有机质促进污染物的消减, 从而提高可溶性有机质对催化降解硝基芳香化合物的实际应用性。     

A common relation for correlating pyrolysis yields of coals and oil shales

Pyrolysis yields for both coals and oil shales exhibit a common relation between the original aromatic carbon content of the sample and the residual organic carbon after pyrolysis. Corresponding measurements of organic carbon distribution by solid-state ¹³C n.m.r. and pyrolysis yields by Fischer assay or proximate analysis have been correlated for 125 coal and oil shale samples composed of widely differing types of organic matter and inorganic constituents. Even though these measurements have been accumulated from various laboratories using different instrumentation and interpretative procedures, there is a remarkably high degree of correlation between original aromatic carbon and residue carbon. The common relation between pyrolysis yield and organic carbon distribution generally supports the previous notion that aromatic carbon is resistant to volatilization and extends this same characterization of pyrolysis behaviour to oil shale kerogen as well as coal.     

Solvothermal synthesis and structure of a neutral layered borate B3O4(OH)(C4N2H10)0.5 containing helical chains

A new neutral layered borate B₃O₄(OH)(C₄N₂H₁₀)_0.5 (denoted BO-CJ 38) has been solvothermally synthesized. The piperazine molecules act as organic ligand and strcuture-directing agent. The left- and right-handed helical B–O–B chains are linked together via piperazine molecules to form infinite organic–inorganic hybrid layers. The aromatic piperazine molecules may play an important role in the formation of helical inorganic chains.     

Effect of dopant type on the properties of polyaniline

The comparative study on the effect of different type of dopants on the properties of polyaniline (PANI) is relative less although dopant has profound effect of the properties of PANI. So, the aim of the present work is to study the effect of different type of dopant, namely strong inorganic hydrochloric acid (HCl), organic and aromatic acids containing different aromatic substitution, namely p‐toluene sulfonic acid (PTSA), dodecylbenzenesulfonic acid (DBSA), organic and aliphatic acids having long hydrocarbon chain, namely lauric acid (LA), on the properties of PANI. The PANI was prepared through oxidative polymerization methods and doped with HCl, PTSA, DBSA, and LA and then characterized through different methods like conductivity measurement, UV, X‐ray, DSC, TGA, and SEM. It was found that the properties of doped PANI depend on the type and molecular size of the dopant. With the increase in dopant chain length, the crystallinity is decreased, whereas the d‐spacing, interchain separation, and solubility are increased. The bond formation of water molecules with the backbone nitrogen of the polymers is much less in presence of aromatic dopants when compared with those of inorganic or aliphatic dopants. All the doped polyanilines under investigation do not decompose up to 500°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Solvothermal in situ metal/ligand reactions: a new bridge between coordination chemistry and organic synthetic chemistry

Several important solvothermal (including hydrothermal) in situ metal/ligand reactions and their mechanisms, including dehydrogenative carbon-carbon coupling, hydroxylation of aromatic rings, cycloaddition of organic nitriles with azide and ammonia, transformation of inorganic and organic sulfur, as well as the CuII to CuI reduction, are outlined in this Account. The current progress clearly demonstrates the important potential of such reactions in the crystal engineering of functional coordination compounds and one-pot synthesis of some unusual organic ligands that are inaccessible or not easily obtainable via conventional methods, thereby substantiating our expectation that a new bridge has been created between coordination chemistry and synthetic organic chemistry.     

Organic coated solids in athabasca bitumen: Characterization and process implications

Bitumen, separated from oil sands by the hot water extraction process, contains ultra‐fine (< 200 nm), inorganic solids (BS). Surfaces of BS particles are coated with toluene insoluble organic matter (TIOM). This organic material is polar and aromatic with contributions from both humic and asphaltene‐like components. Although the surfaces of BS particles are dominated by TIOM, the coverage is patchy rather than continuous. As a result, these solids are capable of stabilizing fine water emulsions in the bitumen phase. The nature of the organic matter on the surfaces of the particles is such that it has a high propensity to form coke. Therefore, these particles can also play a role in fouling on equipment and catalysts.     

包核法对有机颜料改性技术进展

综述了近年来包核法技术在有机颜料改性方面的进展,重点介绍了有机包核颜料的制备机理,以及以S iO2、TiO2和其他一些无机物对有机颜料进行包覆的实例。对有机包核颜料的应用前景进行了展望。     

Carbonization of coal pitch with additives

The ability of organic and inorganic additives (polyethylene terephthalate, titanium dioxide, finely disperse carbon, petroleum bitumen) to reduce the carcinogenic impact of coal-pitch carbonization is studied. Additives may reduce the quantity of pitch sublimates and their content of carcinogenic polycyclic aromatic hydrocarbons. Some additives are able to reduce the benz[a]pyrene content in the exhaust gases, but its complete elimination is impossible, since benz[a]pyrene is a natural product of the high-temperature pyrolysis of organic materials. For this reason, additions of petroleum products to coal pitch cannot reduce the benz[a]pyrene emissions in the exhaust gases.