On-Line Pyrolysis-Liquid Chromatography of （Meth-） Acrylic Acid in Waterborne Polymers Using Cryogenic Injection

Pyrolysis gas chromatography is not a comprehensive analysis method for the determination of acrylics. Polar acrylic monomers show low abundance by gas chromatography. Because of this, a home-made pyrolysis liquid chromatographic injector by means of cryogenic-focussing is developed to determine the presence and concentration of hydroxyl and carboxyl functional monomers present in water- and solvent-borne acrylics. We have shown the prove-of-principle of using cryogenic-focussing for UPLC （pyrolysis-ultra-performance liquid chromatography） injection.     

Adsorption Studies of Chlorpropham and 3-Chloroaniline on Chemically Activated Halloysite

Chemically modified halloysite proved to be an effective adsorbent for the pesticide chlorpropham and 3-chloroaniline from an aqueous solution. Adsorption experiments were conducted using such procedures as the time-dependent （kinetic） procedure and the concentration dependent （isotherm） procedure. Results indicate that the adsorption process is related to the kind of the studied compound. The equilibrium data are well suited to a Freundlich isotherm in the case of both investigated compounds. Adsorption kinetics of chlorpropham and 3-chloroaniline on acid-treated halloysite was successfully described by pseudo-second order kinetic model and the model of Weber and Morris. From the present study, we suggest that the adsorption of chlorpropham and 3-chloroaniline on the modified halloysite is a rather complex process involving two steps： external mass transfer and intra-particle diffusion.     

The Geometry Effect in a Pioneering Experimental Study on the Batch Crystallization of the CAM

Far from being equivalent to host the process, the vessels play an active role in the crystallization thanks to their differently shaped bottoms. It was clearly pointed out through a meticulous experimental research on the batch crystallization of CAM （citric acid monohydrate） carried out in the years 1997-1998 by the author at the historic laboratories of＂La Sapienza＂ University of Rome. Such pioneering M.Sc. thesis, supervised by Prof. Barbara Mazzarotta （Department of Chemical Engineering）, was already summarized in an informative essay but, since the crystallization operating conditions to optimize were illustrated ＂collectively＂, it seemed necessary a further paper expounding uniquely the geometry effect. Our aim is to use all the data, collected and simulated, in order to show why the round-bottomed crystallizer performed better than the conical-bottomed one with the CAM from aqueous solutions, and why we should discard the flat-bottomed crystallizers.     

Construction of Free Amino Acids Composition Data Base for Food

Significant amounts of free amino acids exist in commercially sold vegetables and fruits. Despite of the fact, only a little information is available about the free amino acid contents in foods. To utilize information of free amino acids in food, we have carried out the experiments to quantitate the free amino acids by derivatized with NBD-F （4-fluoro-7-nitrobenzofurazan） and analyzed on reversed-phase UHPLC （ultra-high pressure liquid chromatography） equipped with ultraviolet visible detector. Almost all of food extracts contained free amino acids including GABA （T-amino butyrate）. Contents of free amino acids vary considerably depending upon vegetables and fruits. Principal free amino acids found in vegetables and fruits were asparagine, glutamine, arginine and GABA, which are involved in important metabolic pathways in human. About 140 species of vegetables and fruits were subjected for the data base. All of the plants and fruits we examined exhibit significant amount of free amino acids, those are clearly distinct from data bases obtained after acid hydrolysis treated food samples. Since glutamate and GABA act as excitatory and inhibitory neurotransmitters in CNS, respectively; free amino acids in vegetables and fruits that we eat daily, should be an important source for the cellular metabolic activities.     

Defluorination of Wet-Phosphoric Acid： Equilibrium and Kinetic Studies

This study describes the advantages of using iron-oxide-pillared MF （montmorillonite） and EDTA （ethylenediaminetetraacetic acid）-pillared MD （montmorillonite） for the removal of fluoride in the phosphoric acid. The MF and MD were characterized by using BET （Brunauer-Emmett-Teller） and SEM （scanning electron microscope） for there to appreciate their textural and structural properties and in order to appraise their capacity in the fixation of the fluorine experimental results of fluorine adsorption show a defluoration of the phosphoric acid passing beyond 90% with both clays with a light performance for the MD. The kinetics of fluorine adsorption on MF and on MD has been measured at different temperatures. Indeed, the adsorbed quantity increases more favorably to temperatures more high. This kinetics could be described by two models： pseudo-first-order or pseudo-second-order, which depends on temperature and the nature of adsorbent. At different temperatures used and with various adsorbents （MD and MF, the pseudo second order model was the most reliable to determine the order of kinetics of adsorption of fluorine, which is also reflected a good correlation coefficient （above 0.99）. The fluoride sorption was reasonably explained with Langmuir or Freundlich isotherms. Thermodynamic parameters such as AG~, AH~, AS~ and kinetic one E,, （apparent activation energy） were calculated in order to understand the nature of sorption process. Results indicate that the mechanism of adsorption of the ion of fluoride on the pillared montmorillonite is an exothermic reaction. During equilibrium conditions, both the systems showed negative Gibbs energy, which indicates stability of system. The values of apparent activation energy for the both clays show that the adsorption of F ions is easier on the MF.     

Pyrolysis of Banana and Coffee Residues after Acid Hydrolysis

The use of the residues from renewable feedstock, besides the production of fuels, but also for the generation of other chemicals products, has become a priority. Superior plants have considerable potential as carbohydrate, aryl and fatty acids sources. However, the separation of the main constituents of the samples is necessary for several purposes in the biorefinery concept. The acid hydrolysis and pyrolysis processes are very promising technology, however, some adjustments in the conditions of pyrolysis are needed for different biomasses since carbohydrates were detected （14%-17%） in the residues after the conventional acid hydrolysis of these uncommon biomasses （coffee husk and banana stem and stalk）. On the other hand, it was showed that, by pyrolysis, it is possible to obtain from the solid residue after acid hydrolysis： pyrogenic carbon （charcoal with a yield of 48.5%-52.7%） for agriculture use （biochar） and valuable chemicals in the pyrolysis oil biooil fraction （that accounted by 26.4%-29.0%, free of water）, such as lignin monomers （32.6%-56.4% of the bio-oil） and fatty acids （30%-52.5%）.     

Trimethyl-1,4-Benzoquinone Synthesis via 2,3,6-Trimethylphenol Catalytic Oxidation by Oxygen in the Presence of Non-Keggin-Type Mo-V-Phosphoric Heteropoly Acid Solutions

In the present study, the modified （non-Keggin-type） aqueous solutions of Mo-V-phosphoric heteropoly acids HaPzMoyVx,Oh （HPA-x＇） were applied as homogeneous catalysts for the two-stage oxidation of TMP （2,3,6-trimethylphenol） by oxygen into TMQ （2,3,5-trimethyl-l,4-benzoquinone）, the latter being the key intermediate in the synthesis of vitamin E. The TMQ yield was analyzed regarding solvent type, reaction temperature, molar HPA-x ＇：TMP ratio, and the concentration of vanadium （V） in the HPA-x＇ solution. The TMQ yield was found to depend strongly on the catalyst redox potential and the rate of electron transfer. The results obtained enabled to establish the optimal reaction conditions as well as to suggest the reaction mechanism. In the target reaction, which proceeds in the two-phase system, the TMQ yield is higher than 99%. After phase separation, the catalyst is rapidly regenerated by oxygen and reused.     

Features of Polymethacrylic Acid and Poly-2-Methyl-5-Vinylpyridine Hydrogels Remote Interaction in an Aqueous Medium

The remote interaction of polymethacrylic acid hydrogel with a poly-2-methyl-5-vinylpyridine hydrogel was studied. The aim of work was to study the dependence of the swelling coefficient, the conductivity and the pH of the water solutions of intergel system at different mass ratios from time were studied. The goal was achieved by using following methods： pH-metry, conductometry and gravimetry.     

Synthesis and Characterization of Cured Allyl/Propargyl Ether Novolac Resins

A new kind of modified thermoset resins were synthesized by phase-transfer Williamson reaction from novolac resin and mixtures of allyl- and propargyl-chlorides. The compositions of the resins were defined by 1H NMR （nuclear magnetic resonanse） spectroscopy and the dependence of the cured materials properties on the composition was established. Increase of a propargyl content resulted in char yield raise and the maximum value had been found for propargylated resin--58%. DSC （differential scanning calorimetry）-analysis of the resins has demonstrated that exothermic enthalpy of the curing process could be adjusted by varying the content of propargyl and allyl groups in the resin.     

Simulation of Curing Process for Propargyl Terminated Novolac Resins

Non-isothermal kinetic simulation analysis was carried for CFRP （carbon fiber reinforced plastic） based on PN （propargylated novolac） resins with various curing enthalpy. The simulation study was performed for CFRP with 40% mass resin content. It was shown that, curing enthalpy of PN resin must be less than 600 J/g to avoid uncontrolled heat emission causing destruction of composite sample.     

压裂返排液中残余硼交联剂掩蔽方法

为处理胍胶压裂返排液中存在的残余硼交联剂,达到返排液重复利用的目的,通过考察多元醇和α-羟基羧酸盐对硼酸的络合作用,筛选出了甘露醇、木糖醇、葡萄糖酸钠等3种高效配体,并对比了其掩蔽残余硼交联剂的应用效果。实验结果表明:3种配体与硼酸在常温下均可形成稳定络合物,能有效抑制硼酸水解成硼酸根离子;在络合反应过程中,配体均与硼酸先生成摩尔比为1:1的过渡态络合物,再进一步与游离配体反应生成2:1络合物;随配体/硼酸摩尔比增大,络合效率逐渐提高,当摩尔比不小于2.5时,硼酸能被完全络合;络合物在碱性和高温条件下均具有较高稳定性,不会释放硼酸或硼酸根离子。利用甘露醇和葡萄糖酸钠为掩蔽剂,对返排液中残余硼交联剂进行有效掩蔽后可以直接配制胍胶冻胶压裂液,其耐温耐剪切能力和破胶性能与清水配制压裂液相当,可用于胍胶压裂返排液的重复利用。     

注硼中子寿命测井施工工艺设计方法研究

注硼中子寿命测井工艺包括注硼施工工艺和测井施工工艺2部分.应用研究表明,从现有仪器性能、产层地质状况、井眼环境等方面着手,针对注硼浓度、注入压力选择、测井时机把握等进行精心设计,能够有效改善和提高注硼中子寿命测井在产层动态参数监测和评价应用中的效能.     

酸化体系中石英的稳定性实验研究

利用X’Pert PRO X-射线衍射分析仪、分光光度仪等手段,系统评价了石英在60℃条件下,与5%HCl、5%HCl＋0.5%HF、5%HCl＋1.0%HF、0.5%HF、1.0%HF、8%HBF4和5%HCl＋7%HBF4七种常见酸体系反应的化学行为,重点分析了酸液中可溶硅离子浓度变化特征及影响因素。研究表明：石英与HF酸、土酸反应快速强烈,前2h硅离子浓度波动大,是硅质沉淀形成的主要时期;与氟硼酸体系反应慢,达最大反应强度长于12h。酸蚀后矿物结构无明显变化,可溶硅离子浓度与长石矿物、粘土矿物上述酸化体系中平均浓度相近。通过快速返排残酸,使用低浓度的HF酸进行酸化,采用过量的后置酸液以及在酸化液中加入相应的阻垢剂可预防砂岩酸化时硅质沉淀的产生。     

硼酸酯型汽车制动液的保护性能探讨

硼酸酯型汽车制动液对金属材料的保护性和橡胶材料的适应性是行车安全的两个重要指标。通过制动液各组分对金属和橡胶材料影响的实验结果比较 ,提出了制动液要达到对橡胶和金属材料的保护作用 ,采用的硼酸酯应为乙二醇类 ( 1 /3)和乙二醇类单醚 ( 2 /3)混合硼酸酯 ,稀释剂应采用二乙二醇单醚或低聚乙二醇单醚。并成功地调配出了两种 ZH 3和 ZH 4型制动液     

双甘油硼酸酯单脂肪酸酯的合成及乳化性能

以硼酸双甘油酯为中间体与月桂酸、油酸、硬脂酸分别反应 ,制备了硼酸酯型表面活性剂。以正交实验结果为基础 ,设计出较佳的酯化条件 :双甘油酯与油酸摩尔比 1∶0 .9,温度 2 2 0℃ ,时间 4h ,催化剂用量 (对脂肪酸质量分数 ) 0 .5 % ,酸转化率 98.5 %。用IR光谱认证了产物的结构。同法得到了月桂酸、硬脂酸的相应硼酸酯。 3种产物均不溶于水 ,对甲苯、二氯乙烷及液体石蜡等的乳化性能均达到或优于Span 80的水平     

HA一体化砂岩酸化酸液体系的研制及其性能评价

常规的砂岩酸化工艺需要多个段塞注入前置液、处理液、后置液等,给生产作业带来了不便和困扰。为此,基于"一步"代"多步"的一体酸概念和高效、集约化的理念,研制了一种主要由有机多元酸(HA)+HCl+HF+高效有机溶剂构成的HA一体化酸液体系,可实现对砂岩储层复杂堵塞的有效解堵。对其缓速性能、有机堵塞物溶解、螯合性能和抑制沉淀性能等的实验评价结果表明:(1)新型HA一体化酸不仅可以达到常规一体化酸"一步"代替"多步"酸化的功效而且还具有良好的缓速性能,可通过控制H+的多级分步电离和在黏土矿物上形成硅酸—膦酸铝膜达到缓速的目的 ;(2)对有机物堵塞物解除效率高;(3)HA一体化酸体系相比常规的APCS(氨基聚羧酸类)螯合剂具有更宽的p H值溶解范围,对Ca~(2+)、Mg~(2+)、Fe~(3+)的螯合能力比常规螯合剂(EDTA、NTA、DTPA等)更强,抑制金属氟化物、氟硅酸碱金属和氟铝酸碱金属、氢氧化物沉淀比多氢酸、氟硼酸、土酸效果更优异。该研究成果为高温深层油气藏的解堵提供了技术支撑。     

焦化汽油催化氧化及萃取深度脱硫研究

以空气作氧化剂,硼酸作催化剂,甲醇作萃取剂,用催化氧化与萃取分离相结合的方法,对焦化汽油进行了氧化萃取脱硫研究。结果表明,在空气压力为0．4MPa,硼酸／汽油质量比为4：100,氧化温度为50℃,氧化时间为40min的最佳处理条件下,汽油的硫含量可从1052．000μg／g降至144．124μs／g,脱硫率为86．3％,汽油的收率为92．50％。     

催化裂化汽油氧化吸附脱硫的研究

以氧气为氧化剂,硼酸为催化剂,活性白土为吸附剂,将催化氧化与吸附相结合,对催化裂化汽油进行了氧化吸附脱硫研究。结果表明,在氧气压力为2.0 MPa,氧化温度为80℃,氧化时间为60 min,催化剂用量占原料汽油的质量分数为3%,原料汽油与吸附剂质量比为20的优化条件下,汽油中的硫含量可从571.00μg/g降至68.52μg/g,脱硫率为88.00%,汽油的收率为83.4%。     

碳酸盐岩自转向酸酸岩反应动力学实验研究

酸岩反应动力学参数为正确分析酸岩反应速率规律、指导基质酸化/酸压施工设计提供了基础。利用旋转岩盘实验仪进行碳酸盐岩自转向酸酸岩反应动力学参数的测定,建立了酸岩反应动力学方程,并分析其影响因素。结果表明,自转向酸具有较低的反应速率及传质速率,其在80℃、500r/min、7.5MPa条件下,酸岩反应级数m=1.144,反应速率常数K=4.34×10-(7mol·L)-m·mol(/cm2·s),反应速率方程为J=4.34×10-7Ct1.144;其活化能Ea=34991J·mol-1,频率因子K0=6.53×10-2(mol·L)-m·mol(/cm2·s),酸岩反应动力学方程为J=6.53×10-2e-34991/RTC1.144;并通过转速～De及Re～De分析可知,影响H+有效传质系数的因素包括转速和酸液浓度。     

一氧化碳和亚硝酸酯合成草酸酯和草酸

研究了在Ｐｄ／α－Ａｌ２Ｏ３催化剂上，一氧化碳和亚硝酸酯偶联合成草酸酯、草酸酯水解、副产ＮＯ再生成亚硝酸酯的反应。其催化活性为１０００ｈ，平均时空产率为：６１１．５ｇＤＭＯ／Ｌｃａｔ·ｈ，草酸酯水解为草酸的收率＞９８％，ＮＯ回收率＞９５－％。提出一氧化碳偶联反应机理