CO(υ)高振动激发态向C2H2的振动传能研究

用时间分辨富里叶红外发射谱研究了高振动激发态ＣＯ向Ｃ２Ｈ２的传能，得到了ＣＯ（ｖ＝１－３）各振动态布居及其随时间的变化。利用微分法解出弛豫微分方程组，获得ＣＯ（ｖ＝１－３）向Ｃ２Ｈ２的传能速率常数分别为：２．０±０．１，６．０±０．２和９．４±０．８（１０＾－１３ｃｍ＾３·ｍｏｌｅｃｕｌｅ＾－１·ｓ＾－１）。传能速率随着振动量子数的增加而迅速增加。ＣＯ的振动能应向Ｃ２Ｈ２的对称伸缩模ｖ２近共振Ｖ－     

镉（Ⅱ）—1—苯基—3—甲基—4—苯甲酰基—吡唑啉酮—5配合物吸附波的研究

在ＰＨ４．８的ＨＡｃ－ＨＮ４Ａｃ介质中，Ｃｄ（Ⅱ）与１－苯基－３－甲基－４－苯甲酰基－吡唑啉酮－５（ＰＭＢＰ）生成配合物，于－０．６７Ｖ（ｖｓ．ＳＣＥ）出现一尖锐、灵敏的极谱波。镉含量在０．００１－１．０μｇ／ｍＬ范围内与峰高成线性关系。     

铜（Ⅱ）锌（Ⅱ）—氟哌酸体系电化学行为及示波极谱法研究

铜（Ⅱ）和锌（Ⅱ）分别在０．１ｍｏｌ／ＬＫＨ２ＰＯ４－Ｎａ２ＨＰＯ４缓冲溶液（ｐＨ６．５）和０．２５ｍｏｌ／ＬＮＨ４Ｃｌ溶液中，与氟哌酸形成良好的络合吸附波，峰电位分别为－０．２６Ｖ和－１．２８Ｖ（ｖｓ．ＳＣＥ），络合比分别为１：３和１：２，峰电流与铜（Ⅱ）和锌（Ⅱ）的浓度均在４．０×１０＾－７～５．０×１０＾－６ｎｏｌ／Ｌ范围内呈线性关系，检测限分别为７．０×１０＾－８和５．０×１０＾－８ｍｏｌ     

NH_3－PDS法焦炉气脱硫脱氰的模拟研究

本文介绍了以焦炉气中自有的ＮＨ＿３为碱源，在ＰＤＳ（双核酞菁钴磺酸盐）的催化作用下，脱除煤气中Ｈ＿２Ｓ、ＨＣＮ的工艺模拟研究，提出了新的焦炉气净化工艺流程，称为Ａ－ＰＤＳ工艺。选择出了适宜的工艺条件，可将煤气中Ｈ＿２Ｓ由５～７ｇ／ｍ￣３脱至２０ｍｇ／ｍ￣３以下，脱除率达９９％以上；可将ＨＣＮ由０．８～１．３ｇ／ｍ￣３脱至２０ｍｇ／ｍ￣３以下，脱除率达９８％。     

甲醇催化氧化重整反应制氢的研究

研究了Ｃｕ／Ｚｎ／Ａｌ系列催化剂催化甲醇氧化重整反应制氢,得到活性,选择性及稳定性较好的催化剂Ｃｕ６０Ｚｎ３０Ａｌ５Ｃｅ５;并且考察了Ｃｕ６０Ｚｎ３０Ａｌ５Ｃｅ５为催化剂时,该反应的工艺条件如温度,物料配比等,当压力为０．１ＭＰａ,温度为２４０℃,ＣＨ３ＯＨ：Ｈ２Ｏ＝１：０．８,ＣＨ３ＯＨ：Ｏ２＝４：１时,甲醇的转化率达９７．７５％,在此反应条件下,反应１００ｈ后,甲醇的转化率仍在９６％以上。     

双（取代环戊二烯基）二氯化锆的晶体结构分析

用Ｘ－射线晶体结构衍射法测定了双［１－苄基－１－乙基丙基环戊二烯基］二氯化锆［η５－Ｃ５Ｈ４Ｃ（Ｃ２Ｈ５）２ＣＨ２Ｃ６Ｈ５］２ＺｒＣｌ２（Ｉ）及（１，２－二异丁基－１，２－甲基－乙基桥联）双环戊二烯基二氯化锆［η５－Ｃ５Ｈ４Ｃ（ＣＨ３）（Ｃ４Ｈ９－ｉ）Ｃ（ＣＨ３）（Ｃ４Ｈ９－ｉ）Ｃ５Ｈ４－η５］ＺｒＣｌ２（Ⅱ）的结构。二者皆为单斜晶系，（Ｉ）的空间群为Ｐ２／ｎ，ａ＝１２．５８２（３），ｂ＝７．９９２（２），ｃ＝１４．９７９（３）Ａ，β＝１０１．６８（１）°，Ｖ＝１４７４．９（９）Ａ３，Ｍｒ＝６１２．８４，Ｚ＝２，Ｄｘ＝１．３８ｇ／ｃｍ３，μ＝５．６９ｃｍ（－１），Ｆ（０００）＝６４０，Ｒ＝０．０３３，Ｒω＝０．０３６。（Ⅱ）的空间群为Ｃｃ，ａ＝１３．３０９（３），ｂ＝９．５９１（１），ｃ＝１６．４４９（８）Ａ。β＝４．８３（３）°，Ｖ＝２０９．２（２）Ａ３，Ｍｒ＝４５８．６３，Ｚ＝４，Ｄｘ＝１．４５６ｇ／ｃｍ３，μ＝７．７７ｃｍ（－１），Ｆ（０００）＝９５２，Ｒ＝０．０５１，Ｒω＝０．０６１。化合物（Ｉ）以重叠式存在，两个苄基处于反式。晶体（Ⅱ）以交叉式存在，甲基、异丁基以反式构象存在。     

不经分离,高敏,连续光度滴定混合物中钕和铁

提出以Ｆｅ（３＋）（Ｎｄ（３＋）－ＣＡＳ－ＣＰＢ－Ｃ２Ｈ５ＯＨ作为不经分离、高敏、连续光度配合滴定混合物中Ｆｅ（３＋）和Ｎｄ（３＋）的多元胶束配合指示体系。滴定Ｆｅ（３＋）和Ｎｄ（３＋）的适宜ｐＨ分别为２．３～３．２和６．０～８．６。用ＥＤＴＡ目视滴定Ｆｅ（３＋）时，终点处由蓝紫变粉红色，对比度大（Δλ＝１３０ｎｍ）、灵敏度高（配合物摩尔吸光系数ε（６３０）＝１．１４×１０５Ｌ·ｃｍ（－１）·ｍｏｌ（－１），至少可检测０．４μｇ／ｍＬ，滴定线性范围为０～２．８μｇ／ｍＬ。线性相关系数为０．９９９４；目视滴定Ｎｄ（３＋）时，终点处由绿色变橙黄，Δλ＞１８０ｎｍ，ε（６３０）＝７．６×１０４，至少可检测１μｇ／ｍＬ，滴定线性范围０～３．７μｇ／ｍＬ，线性相关系数０．９９９４。对于铁钕硼混合物样品则不经分离在６３０ｎｍ处连续光度滴定，可更精密、高敏、准确地确定终点，变异系数１．７６％～２．８６％，标准加入回收率９６％～１０４％，且简便、快速。     

[（C5H4CH3）2HoN4cpH]2.[（C5H4CH3）（C5H5）HoN4CPh]2的合成和晶体结构2

（Ｃ５Ｈ４ＣＨ３）３Ｈｏ和（Ｃ５Ｈ４ＣＨ３）２Ｈｏ（Ｃ５Ｈ５）与５－本基四唑在ＴＨＦ中反应，得到了复合产物「（Ｃ５Ｈ４ＣＨ３）２ＨｏＮ４ＣＰｈ」２．「（Ｃ５Ｈ４ＣＨ３）（Ｃ５Ｈ５）ＨｏＮ４ＣＰｈ」２，该晶体属三斜晶系，Ｐ１空间群，晶胞参数为ａ＝９．３８６（３），ｂ＝１３．０７１（３），ｃ＝１６．５７１（２）Ａ，α＝８６．９０（１），β＝７４．６１（２），γ＝７７．３０（２）°，Ｖ＝１９１２．８（８     

铜与三乙四胺六乙酸配合物［Cu_2（H_2TTHA）（H_2O）_2］·6H_2

首次在水溶液中合成了三乙四胺六乙酸铜配合物单晶，元素分析结果表明可用Ｃｕ２（Ｈ２ＴＴＨＡ）·８Ｈ２Ｏ表示．用Ｘ射线衍射方法测定了该单晶结构，其结构式为［Ｃｕ２（Ｈ２ＴＴＨＡ）（Ｈ２Ｏ）２］·６Ｈ２Ｏ．晶体属单斜晶系．空间群为，每一晶胞中有２个配合物单元，形成二核配合物．晶胞参数如下：ａ＝０．７１６２（４），ｂ＝１．３０７７（８），ｃ＝１．５８３９（９）ｎｍ；β＝９１．６６（５）°，Ｚ＝２，ｖ＝１．４８３（２）ｎｍ３，ｄｃａｌｃ＝１．７０６ｇ／ｃｍ３．配合物铜的配位数为５，构型为四方锥配位多面体．     

CH（B~2Σ~－）和卤代甲烷、CS_2、O_2及Ar碰撞过程动力学研究

用四倍频ＹＡＧ激光（２６６ｎｍ）光解ＣＨＢｒ_３产生ＣＨ（Ｂ~２Σ~－）自由基，通过测量自发辐射ＣＨ（Ｂ→Ｘ）的时间分辨信号测得室温下ＣＨ（Ｂ）被卤代甲烷、ＣＳ_２、Ｏ_２及Ａｒ的猝灭速率常数（×１０~（－１０）ｃｍ~３·ｍｏｌｅｃ~（－１）·ｓ~（－１））分别为４．４±０．７（ＣＨ_２Ｃｌ_２）、５．２±０．４（ＣＨＣｌ_３）、５．０±０．７（ＣＣｌ_４）、８．２±０．３（ＣＨＢｒ_３）、７．９±０．７（ＣＳ_２）、０．１９±０．０２（Ｏ_２）及（１．１±０．１）×１０~（－２）（Ａｒ）．结果表明，除Ｏ_２外，其它猝灭剂对ＣＨ（Ｂ）的猝灭速率常数均大于对ＣＨ（Ａ）的。对卤代甲烷分子，猝灭速率常数显示了因Ｃｌ原子数增加而增加的趋势。     

Carbon Dioxide/Methane Separation by Adsorption on Sepiolite

In this work,the use of sepiolite for the removal of carbon dioxide from a carbon diox- ide/methane mixture by a pressure swing adsorption(PSA)process has been researched.Adsorption equilibrium and kinetics have been measured in a fixed-bed,and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained.A model based on the LDF approxima- tion has been employed to simulate the fixed-bed kinetics,using the Langmuir equation to describe the adsorption equilibrium isotherm.The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied.The experimental results were compared with the ones predicted by the model adapted to a PSA system.Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle.These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases.     

Dynamic Adsorption and Desorption Behaviors of Cu(II), Ag(I), and Au(III) on Silica Gel Microspheres Encapsulated by Salicylic Acid–Functionalized Polystyrene

Composite material silica gel microspheres encapsulated by salicylic acid functionalized polystyrene(SG–PS–azo–SA) have been synthesized, and the dynamic adsorption and desorption properties of this silica gel matrix inorganic–organic composite material for Cu(II), Ag(I), and Au(III) have been investigated. The results displayed that SG–PS–azo–SA had excellent adsorption for Cu(II), and the film diffusion dominated the adsorption process of SG–PS–azo–SA for Cu(II), Ag(I), and Au(III). These metal ions could be desorbed with the eluent solution of 2.5 mol/L HCl, 3% thiourea in 0.5 mol/L HCl, and 0.5% thiourea in 1 mol/L HCl, respectively. When the elution was carried out for 30 min, 30 min, and 132 min, the desorption ratio ω could reach 91.1%, 99.4%, and 60.84%, respectively. Thus, silica gel encapsulated by polystyrene coupled with salicylic acid (SG–PS–azo–SA) is favorable and useful for the removal of metal ions Cu(II), Ag(I), and Au(III), and the high adsorption capacity make it a promising candidate material for the metal ions removal.     

Study on Pressure Swing Adsorption Removing C2^＋ from Natural Gas as Raw Material for Thermal Chlorination

The experimental investigation demonstrates that a setisfactory can be expected for pressure swing adsorption (PSA) purification of natural gas as raw material for thermal chlorination process.Using hh-4 molecular sieve as adsorbent for removing C2^ components,the suitable adsorption pressure is 0.4-0.45 MPa,desorption vacuum is 0.08-0.09 MPa and circulation time is 20-21 min.     

Study on Pressure Swing Adsorption Removing C+2 from Natural Gas as Raw Material for Thermal Chlorination

The experimental investigation demonstrates that a satisfactory result can be expected for pressure swing adsorption (PSA) purification of natural gas as raw material for thermal chlorination process. Using hh-4 molecular sieve as adsorbent for removing C2 components, the suitable adsorption pressure is 0.4-0.45 MPa, desorption vacuum is 0.08-0.09 MPa and circulation time is 20-21 min.     

Parametric Study of a Pressure Swing Adsorption Process

The performance of a pressure swing adsorption (PSA) process for production of high purity hydrogen from a binary methane-hydrogen mixture is simulated using a detailed, adiabatic PSA model. An activated carbon is used for selective adsorption of methane over hydrogen. The effects of various independent process variables (feed gas pressure and composition, purge gas pressure and quantity, configuration of process steps) on the key dependent process variables (hydrogen recovery at high purity, hydrogen production capacity) are evaluated. It is demonstrated that many different combinations of PSA process steps, their operating conditions, and the feed gas conditions can be chosen to produce an identical product gas with different hydrogen recovery and productivity.     

Effect of Enzyme Modification of Corn Grits on their Properties as an Adsorbent in a Skarstrom Pressure Swing Cycle Dryer

Corn grits have been tested as a desiccant in a pressure swing adsorption (PSA) system to produce dry air. Two sizes of unmodified corn grits were tested in the PSA system: 2.16 and 0.978 mm in diameter, which dried moist air to dew points of –42°C and –69°C, respectively. A modification technology has been developed for the corn grits that gives an increase in the operational adsorptive capacity in a pressure swing adsorption system, so that they remove as much moisture from air as molecular sieves at the same conditions. After modification, 2.16 mm corn grits dry moist air to a –56°C dew point and the 0.978 mm corn grits dry air to a –80°C dew point. The modification process creates surface modifications on the corn grits apparently making more adsorption sites easily available. The modification procedure increases the specific surface area of the grits and possibly decreases the crystallinity, which would make more hydroxyl groups available for adsorption of water. Possible applications of using corn grits in the pressure swing adsorption system include industrial gas dryers, sorptive cooling air conditioners, and recycling equipment for industrial solvents.     

Effect of Operation Symmetry on Pressure Swing Adsorption Process

In a multi-bed pressure swing adsorption (PSA) process, cycle steps with gas flow transferring from one bed to another such as equalization, purge, etc. are generally practiced to enhance the product recovery. However, if the flows for the connected beds in these steps are not balanced, the PSA process may not operate in a symmetrical manner. In the modeling of the PSA process, most of the simulations consider only one bed and assume that the rest of the beds would behave in a same way. In order to assess the impact of bed symmetry on the PSA performance, a new PSA model capable of studying bed symmetry in a two-bed system is developed. Experimental results from this paper show that uneven equalization flow can result in a lower product purity and a peculiar purity curve at different equalization levels. This phenomenon can be successfully predicted by this model. Simulation results also show that in large-scale PSA units, asymmetrical operation can cause drastically different temperature profiles in different adsorbers and hence a much lower performance. This paper demonstrates the importance of maintaining operation symmetry in PSA processes.     

Production of oxygen enriched air by rapid pressure swing adsorption

A novel rapid pressure swing adsorption (RPSA) process is described for production of 25–50% oxygen enriched air. The embodiment consists of one or more pairs of adsorbent layers contained in a single adsorption vessel. The layers undergo simultaneous pressurization-adsorption and simultaneous depressurization-purge steps. A total cycle time of 6–20 seconds is used. The process yields a very large specific oxygen production rate and a reasonable oxygen recovery for production of 20–50 mole% oxygen enriched gas.It is demonstrated by a simple mathematical model of isothermal single adsorbate pressure swing ad(de)sorption concept on a single adsorbent particle that the specific production rate of a PSA process cannot be indefinitely increased by reducing the cycle time of operation when adsorbate mass transfer resistances are finite.     

Pressure Swing Adsorption Technologies for Carbon Dioxide Capture

The principles of pressure swing adsorption (PSA) for carbon dioxide capture are reviewed. Previous work on PSA, relevant modeling and experimental investigation for specifically carbon dioxide separation are also presented and significant findings highlighted. Simple rules for PSA process design based on analysis of the inherent properties of adsorbate-adsorbent systems encompassing equilibrium isotherm, adsorption kinetics, shape of breakthrough curves, screening and selection of adsorbent, bed porosity, adsorption time, purge to feed ratio, residence time, pressure equalization and rinse steps are provided to promote better understanding of the technology so that it gains wider acceptance in the future to address the global environmental concern, particularly in the removal of carbon dioxide as a greenhouse gas.     

Piston-driven ultra rapid pressure swing adsorption

The piston-driven ultra rapid pressure swing adsorption (URPSA) equipment was developed and oxygen enrichment from air was examined as an example. The adsorbent bed is directly connected to the cylinder where a piston moves at high frequency. Thus pressurization and depressurization in the bed are driven by mechanical piston motion, which can achieve far more rapid cycles compared with the conventional pressure swing operation using valves. The cycle time is usually on the order of seconds or sub seconds. Oxygen enrichment from air up to about 60% or higher of oxygen concentration was achieved by small-scale equipment using zeolite 5A with a oxygen production capacity of 100 Nm³-product gas/m³-zeolite/hr, which is about ten times larger than those of commercialized PSAs for this purpose.A simplified numerical model describing the mass transfer taking place in URPSA was developed. The model could simulate fairly well the air separation characteristics in terms of oxygen concentration, oxygen production capacity and oxygen yield. The proposed model helps in the understanding of the basic nature of URPSA and possible applications. This novel PSA is promising as a compact yet high-capacity PSA to be utilized in a wide variety of applications.