洗涤剂用沸石的钙离子交换性能的研究

作为洗涤剂助剂,沸石的主要作用是通过离子交换降低水中的钙镁离子浓度、软化洗涤用水以提高洗涤剂中的表面活性剂的洗涤效率。因此,沸石对钙镁离子交换容量的大小和交换速率的快慢是评价洗涤用沸石的重要质量指标［１,２］。目前,使用最多的沸石类助剂为ＮａＡ沸石。为了弥补ＮａＡ型沸石镁离子交换能力的不足,先后又出现了Ａ、Ｘ型沸石混合使用［３］、高铝Ｘ型沸石(ＭＡＸ)［４～５］和高铝Ｐ型沸石(ＭＡＰ)等技术［１,２］。ＭＡＸ型和ＭＡＰ型沸石与ＮａＡ型沸石一样具有最小的硅铝比(ＳｉＯ２／Ａｌ２Ｏ３＝２)。因此,这三种沸石的…     

β-沸石骨架铝化改性的红外光谱

β沸石是以有机胺为模板剂合成的高硅沸石．为在孔道中进行吸附和催化反应,通常是在空气中 (５５０℃ )进行焙烧,将有机胺脱除并使质子酸中心形成．但这种脱模板剂方法,会造成骨架脱铝［１ -４］,使质子酸中心显著减少．β沸石固有结构中存在着孔道位错和结构空穴,空气中焙烧脱有机胺可能会进一步损伤沸石的骨架结构［４,５］．沸石骨架改性已发展了多种铝化方法［６ -８］．有的研究工作表明,通常用红外光谱和ＭＡＳＮＭＲ表征的非骨架铝,在温和的条件下,例如回馏温度下的离子交换或者在较低温度下 (１００℃或室温 )与碱反应就可…     

合成A型分子筛的矿物原料中石英的转化与活化

合成Ａ型分子筛的矿物原料中石英的转化与活化赵经贵，张斌，刘景茂，张新，霍丽华，陈耐生（黑龙江大学化学系哈尔滨１５００８０）（福州大学化学系福州）关键词　石英，高岭土，转化，活化，分子筛由高岭土、煤矸石合成Ａ型分子筛［１～３］，其中所含石英杂质影响分子...     

高硅Y沸石的研制及吸附热力学性质

Ｙ沸石用ＬｉＣｌ溶液交换得ＬｉＮａＹ沸石,再经ＳｉＣｌ４气相同晶取代进行脱铝补硅,获得高结晶度的高硅Ｙ沸石,硅铝比可大于１００［１］．在脱铝过程中,随着硅铝比的升高其孔结构和表面性质均发生变化,直接关联到Ｙ沸石在炼油中的催化裂化性能．通过对不同大小、结?..     

电解还原法生产的对氨基苯酚纯度及杂质4，4＇－二氨基二苯醚的高效液相色谱分析

电解还原法生产的对氨基苯酚纯度及杂质４，４＇－二氨基二苯醚的高效液相色谱分析尤进茂，孙学军，李怀娜，周连君（曲阜师范大学化学系曲阜２７３１６５）１前言对氨基苯酚（ＰＡＰ）是制造显影剂、药物扑热息痛和偶氮染料的重要中间体［１～３］，用途十分广泛。虽然工...     

新型洗涤剂用沸石MAP的合成及其性能表征

在ＳｉＯ_２－Ａｌ_２Ｏ_３－Ｎａ_２Ｏ－Ｈ_２Ｏ体系中,采用加入晶种的方法水热合成出新型洗涤剂用沸石－ＭＡＰ。其硅铝比（Ｓｉ／Ａｌ）在 １．０７－１．１３之间,平均晶粒直径小于０．４μｍ,钙离子交换容量为２９０～３１３ ｍｇＣａＣＯ_３／ｇ（干沸石）,非离子表面活性剂的吸附量在 ８３～ １００ｇ ｏｉｌ／１００ｇ（沸石）之间。本文着重考察了影响合成 ＭＡＰ沸石的因素,确定了ＭＡＰ沸石会成的最佳范围,并对其物理化学性质进行了表征。     

KAIF_4化合物的合成

ＫＦ－ＡＩＦ_３体系中介于ＫＡＩＦ_４和Ｋ_３ＡＩＦ_６之间的共晶点组成的熔盐作为钎剂大量用于各类铝散热器的钎焊,工业上称为Ｎｏｃｏｌｏｋ方法［１,２］。以ＫＡＩＦ_４为主体的Ｎｏｃｏｌｏｋ钎剂［１］合成方法虽有多种并已见诸文献报道［２－８］,但为深入研究Ｎｏｃｏｌｏｋ钎剂的特征,研究纯ＫＡＩＦ_４的制备非常必要。Ｅｉｔｅｌ等人报道用熔融ＫＦ和ＡＩＦ_３的方法,制得了纯ＫＡＩＦ_４［９］。Ｂｒｏｓｓｅｔ［４］则认为熔融ＫＦ和ＡＩＦ_３得不到纯的ＫＡＩＦ_４,他在水溶液中以定比例混合ＨＦ,ＡＩＦ_３和ＫＨＦ_…     

甲苯—2,4—二异氰酸酯修饰蒙脱土及聚苯乙烯／蒙脱土纳米复合材料？…

用ＦＴＩＲ和ＷＡＸＤ法研究了甲苯－２,４－二异氰酸酯（ＴＤＩ）的邻位和对位异氰酸酯基因与蒙脱土表面羟基的修饰反应,在此基础上提出了结构模型;用ＴＤＩ修饰后的蒙脱土成功制备了插层型聚苯乙烯／蒙脱土纳米复合材料,并用ＷＡＸＤ和ＴＥＭ进行了表征。实验结果表明,修饰后ＴＤＩ与蒙脱土表面形成化学键,使蒙脱土的片层间距显著增大,十六烷基三甲基溴化铵（ＣＴＡＢ）在蒙脱土层间由双层平行排列转变为双层脂肪链倾斜方式     

无金属酞菁中杂质硫的化学价态

无金属酞菁中杂质硫的化学价态周淑琴金祥凤刘世宏（中国科学院化学研究所北京１０００８０）作为有机光导材料的酞菁化合物在静电复印特别是激光印刷机中是重要的载流子产生材料之一［１，２］，在研究酞菁双层感光膜［３］和杂质分析［４］中，发现无金属酞菁中微量杂质...     

NaY沸石草酸脱铝

ＮａＹ沸石用草酸溶液脱Ａｌ，随草酸用量增加，脱Ａｌ度增加，结晶度下降，但脱Ａｌ２０％仍能保持９５％以上的高结晶度，实验结果表明，脱Ａｌ量和Ｈ用量呈线性关系，斜率近似０．２５，Ｃ２Ｏ＾２－４有促进脱Ａｌ的作用，脱Ａｌ过程中沸石结晶度的保持３于脱Ａｌ体系的缓冲作用，由草酸的电了平衡和络合平衡构成的脱Ａｌ体系档提供最佳脱Ａｌ条件，脱Ａｌ的沸石产物带有羟基“窝”八面沸石骨架，加热３００℃以上可使羟基“窝”     

Comparison of calibration methods in quantitative diffuse reflectance infrared spectroscopy

Four different calibration methods were used for quantitative analysis of quartz and calcite in atmospheric aerosols by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS): (A) conventional calibration with one measurement on each standard (single calibration); (B) calibration with an internal standard; (C) calibration with parallel (n = 4) measurements on each standard (multiple calibration); (D) multiple calibration followed by reference reflectance correction. The accuracy and the precision of the methods were compared and it was found that by using method D the reliability of the conventional pellet preparation transmission technique can be achieved.     

Determination of analytical limits in solid sampling ETAAS: a new approach towards the characterization of analytical quality in rapid methods

In the present study the lower analytical limits of solid sampling electrothermal atomization atomic absorption spectrometry (SS-ETAAS) were characterized by means of blank measurements and – for the first time – by means of the calibration curve method, where a calibration near the range of these limits (limit of decision, detection and quantification) was performed. The limit of decision as derived from blank measurements was calculated according to the 3σ-criterion to be 0.003 and 0.019 ng for Cd and Pb, respectively. For Pb and Cd a roughly threefold increase of these limits was observed when the calibration method according to DIN 32 645 was applied. When solid reference material was used, only a slight increase could be observed. The analytical limits were 2 to 20 times lower than reported for sample decomposition methods. The blank measurement and conventional calibration curve method, however, do not account for factors relating to solid sampling such as sample mass and matrix. Therefore, the calibration curve model was applied to data derived from comparisons between direct solid sampling ETAAS and a compound reference method (ETAAS following sample homogenization and digestion). The observed analytical limits were not found to be substantially increased if enough samples with low element contents were available for calibration. Coupling of the calibration curve model with the comparison of methods included real test samples and thus the relevant maximum sample mass and analyte content in the range of the lower analytical limits. As validation procedures frequently include comparisons of methods, the present approach might prove to be of some general interest for the characterization of analytical quality in rapid methods.     

Determination of analytical limits in solid sampling ETAAS: a new approach towards the characterization of analytical quality in rapid methods

In the present study the lower analytical limits of solid sampling electrothermal atomization atomic absorption spectrometry (SS-ETAAS) were characterized by means of blank measurements and--for the first time--by means of the calibration curve method, where a calibration near the range of these limits (limit of decision, detection and quantification) was performed. The limit of decision as derived from blank measurements was calculated according to the 3sigma-criterion to be 0.003 and 0.019 ng for Cd and Pb, respectively. For Pb and Cd a roughly three-fold increase of these limits was observed when the calibration method according to DIN 32 645 was applied. When solid reference material was used, only a slight increase could be observed. The analytical limits were 2 to 20 times lower than reported for sample decomposition methods. The blank measurement and conventional calibration curve method, however, do not account for factors relating to solid sampling such as sample mass and matrix. Therefore, the calibration curve model was applied to data derived from comparisons between direct solid sampling ETAAS and a compound reference method (ETAAS following sample homogenization and digestion). The observed analytical limits were not found to be substantially increased if enough samples with low element contents were available for calibration. Coupling of the calibration curve model with the comparison of methods included real test samples and thus the relevant maximum sample mass and analyte content in the range of the lower analytical limits. As validation procedures frequently include comparisons of methods, the present approach might prove to be of some general interest for the characterization of analytical quality in rapid methods.     

Preparation and characterization of nanosized ZSM-5 zeolite using kaolin and investigation of kaolin content, crystallization time and temperature changes on the size and crystallinity of products

Nano sized ZSM-5 zeolite samples were synthesized successively from kaolin clay as alumina source having a large amount of quartz (39%) and silicic acid as silica source by hydrothermal treatment with NaOH in the presence of tetrapropylammonium hydroxide as a template. Then the effect of kaolin content, crystallization temperature and time on the size and crystallinity of the products were investigated. The prepared samples were characterized using XRD, SEM, EDS and FT-IR techniques. The results showed that the synthesized ZSM-5 zeolite samples were almost pure and their crystallization was almost complete. The average particle size, as determined by Debye-Scherrer equation, was in the range of 20-42 nm. Increasing kaolin content on crystal size was more effective than increase in crystallization temperature and time. Additional evidences for the nano sized ZSM-5 zeolite were the asymmetric stretch vibration band at 1225 cm^-1 in the FT-IR spectra and TEM images. The scanning electron micrographs of the synthesized zeolites showed that they are spherical shape crystals.     

Preparation of Tetraethylenepentamine-Functionalized 4A Zeolite for effective removal of phosphate in water

Recently, the high-concentration phosphorus-containing wastewater has been caused lots of negative influences on aquatic environment and thus driven people to develop some effective methods to remove excess of phosphate in water. In order to solve these environmental problem, in this work, a tetraethylenepentamine (TEPA) modified 4A zeolite has been prepared and used for removing phosphate. Removal of phosphate by precipitation of 4A zeolite and electrostatic action of TEPA with phosphate were determined by scanning electron microscopy, X-ray powder diffraction and Fourier infrared spectrum, and morphology and characteristic peak of TEPA-4A zeolite before and after adsorption changed significantly. In addition, the results of batch adsorption studies showed that the pH of the solution have a significant influence on the adsorption of TEPA-4A and the biggest adsorption capacity was 23 mg/g at pH = 2.3 ± 0.2. Adsorption isotherms results showed that the process was consistent with Langmuir model and the maximum adsorption capacity could reach to 28 mg/g at 25 °C. TEPA-4A adsorption processes were spontaneous endothermic reaction, and elevated temperatures were conducive to the adsorption process through kinetics and thermodynamics results. The research of TEPA modified 4A zeolite and raw 4A zeolite provides technical support for the development of 4A zeolite instead of sodium tripolyphosphate as a new type of detergent ingredient.     

Highly Crystallized Nanometer‐Sized Zeolite A with Large Cs Adsorption Capability for the Decontamination of Water

Nanometer‐sized zeolite A with a large cesium (Cs) uptake capability is prepared through a simple post‐milling recrystallization method. This method is suitable for producing nanometer‐sized zeolite in large scale, as additional organic compounds are not needed to control zeolite nucleation and crystal growth. Herein, we perform a quartz crystal microbalance (QCM) study to evaluate the uptake ability of Cs ions by zeolite, to the best of our knowledge, for the first time. In comparison to micrometer‐sized zeolite A, nanometer‐sized zeolite A can rapidly accommodate a larger amount of Cs ions into the zeolite crystal structure, owing to its high external surface area. Nanometer‐sized zeolite is a promising candidate for the removal of radioactive Cs ions from polluted water. Our QCM study on Cs adsorption uptake behavior provides the information of adsorption kinetics (e.g., adsorption amounts and rates). This technique is applicable to other zeolites, which will be highly valuable for further consideration of radioactive Cs removal in the future.     

Improvement of latex piezoelectric immunoassay: Detection of rheumatoid factor

Latex piezoelectric immunoassay is a method for detection of agglutination of antibody- or antigen-bearing latex by immunoreaction using a piezoelectric quartz crystal; the agglutination decreases the oscillation frequency of the crystal. This is advantageous in that coating the surface of the crystal followed by fixation of antibody or antigen is unnecessary. There is, however, a drawback, and to improve this, we designed a micro-cell in which only one side of the crystal is exposed to the solution. A method for regenerating the crystal was also devised. Measurement was carried out using a calibration curve of the frequency change against rheumatoid factor activity. The improvement made it possible to use one crystal repeatedly and reproducibility was satisfactory. The calibration curve became almost independent of the crystal used.     

Sodium-aluminium-silicates in the washing process Part X. Cobuilders and optical brighteners

This study is concerned with the physico-chemical background to the substitution of phosphates in laundry detergents, with special emphasis on combinations of zeolite A with other detergent ingredients, especially water-soluble cobuilders and optical brighteners. The most important action mechanisms of zeolite A / cobuilder systems were investigated for a variety of washing conditions. It is shown that the builder performance of zeolite A is often reinforced by small amounts of water-soluble substances such as polycarboxylates. These detergents are able to compete, in terms of performance, with products containing a high proportion of phosphate. Further, the interaction of zeolite A with fluorescent whitening agents in detergent powders was studied. It is shown that the photophysical properties of a typical optical brightener are negatively influenced by ionic builders and surfactants. In contrast to sodium triphosphate, zeolite A can enhance the appearance of powders even in the presence of anionic surfactants.Lecture presented at the International Symposium on Zeolites, Zeolites as Catalysts, Sorbents and Detergent Builders, Würzburg, September 4–8, 1988.     

环境友好助洗剂——4A沸石

介绍了4A沸石的结构、性质及其作为洗涤助剂等方面的应用和国内外发展状况。     

The determination of quartz in clay materials

The quartz contents (maximum, 4 wt.%) of four clay materials and a tourmaline were determined by differential thermal analysis, by X-ray diffraction and by chemical analysis. The results are used to make a critical comparison of these three methods. DTA gives a better precision than X-ray diffraction analysis. The chemical method is judged unreliable in that feldspar and mica, present as minor components, are recorded in part as quartz.