化工数据与其教学

本文从化工热力学内容着手,说明化工数据的定义、内容及其重要性,并指出化工数据是化工热力学的一个分支。为使学生能掌握相关知识,应在化工热力学加入有关化工数据这一章,使学生能有完整的入门知识。为使有志者更好地进行化工计算,建议开出选修课《化工数据》。     

改性对分子筛酸性和烷基化脱硫性能的影响

对Na型分子筛分别进行不同性质的阳离子交换和热处理,得到了HY,USY,CeY,MgY,Hβ和USβ系列改性分子筛催化剂,并考察了改性分子筛催化FCC汽油烷基化脱硫的活性。通过吡啶吸附红外光谱表征,研究了改性对分子筛的表面酸性和催化活性的影响规律。结果表明,铵改性Y分子筛的酸量远远大于8分子筛。USY的B酸量、L酸量分别增大到了868．583,972．869gmol／g,其中L酸主要以弱酸的形式存在。UBβ的B酸量、L酸量也有所增加,但是强B酸量降低,强L酸量增加。Mg^2＋改性后的NaY分子筛总酸仅次于HY,但强B酸量仅为86．742μmol／g,强L酸量仅为31．335μmol／g;Ce^3＋改性后的NaY分子筛总B酸量和强B酸量仅次于USY,L酸量仅为58．308μmol／g,但无强L酸。结合小于100℃馏分段硫的转化率得出,总B酸量越多,且强B酸量越多（HY除外）,小于100℃馏分段硫的转化率越高。强L酸不利于噻吩类硫化物的烷基化反应。对于μ分子筛,强B酸中心是烷基化反应的主要活性位。     

CO2响应型β?环糊精材料用于稠油降粘

制备了一种环境友好型马来酸酐改性β?环糊精(MAH?β?CD),温和条件下将其与脂肪酸聚醚二胺 (JD230)静电作用合成了具有CO₂响应性的表面活性剂(MJD230)。它能与油形成稳定的水包油乳液进而有效降低溶液的表面张力。CO₂调控下,MJD230可重复用于稠油的乳化降黏和破乳。利用FT?IR对结构进行表征。通过观察降黏率和乳液粒径优化MJD230的合成条件,同时对降黏性能和稳定性进行考察。在质量分数为0.5%,油水体积比为3:7的条件下,MJD230稠油降黏率可达99.19%。利用pH值和电导率的可逆变化证明MJD230溶液对CO₂的响应性和重复性。这为表面活性剂驱油和CO₂捕集相结合提高稠油采收率提供了可行的途径。关键词：稠油;乳化;CO₂响应型表面活性剂;稠油降黏中图分类号：TQ630 文献标识码： A 文章编号：1003?5214 (2023) 05?0000?00     

定位分布贡献方法估算有机物正常沸点

A new position group contribution model is proposed for the estimation of normal boiling data of organic compounds involving a carbon chain from C2 to C18. The characteristic of this method is the use of position distribution function. It could distinguish most of isomers that include cis- or trans-structure from organic com-pounds. Contributions for hydrocarbons and hydrocarbon derivatives containing oxygen, nitrogen, chlorine, bro-mine and sulfur, are given. Compared with the predictions, results made use of the most common existing group contribution methods, the overall average absolute difference of boiling point predictions of 417 organic com-pounds is 4.2 K; and the average absolute percent derivation is 1.0%, which is compared with 12.3 K and 3.2% with the method of Joback, 12.1 K and 3.1% with the method of Constantinou-Gani. This new position contribution groups method is not only much more accurate but also has the advantages of simplicity and stability.     

不同温度压力下纯水、醋酸+水、对二甲苯+醋酸+水黏度测定(英文)

The viscosities of pure water, the acetic acid + water binary system, and the p-xylene + acetic acid + water ternary system at different concentrations were determined with a rolling-ball viscometer at temperatures from 313.15 to 473.15 K and pressures from 0.10 to 3.20 MPa. The viscosity data were fitted by a correlation equation for the estimation of the mixture viscosities. The average absolute deviations (AAD) of the correlation for binary and ternary systems are 2.48% and 1.77%, respectively.     

固体磷酸催化FCC汽油烷基化脱硫的活性和稳定性

实验考察了不同温度焙烧得到的固体磷酸在催化流化催化裂化汽油烷基化脱硫反应中的活性和稳定性.通过x射线衍射(XRD)表征,研究了催化剂的结晶度和晶相比对其催化活性和稳定性的影响.结果表明,随着焙烧温度升高,固体磷酸的结晶度变大,正磷酸硅与焦磷酸硅的晶相比减小;而高结晶度、高正磷酸硅与焦磷酸硅晶相比的固体磷酸催化剂具有较好的活性和稳定性.     

DSC法测定醋酸-水溶液的比热

利用差示扫描热量计(DSC)测定了醋酸水溶液在温度范围为293.15~359.15K和整个组成范围下的比热,并把比热的测量值与文献值进行了比较, 实验的测量误差小于±2%, 测得的醋酸-水的比热数据完全能满足工程设计的需要。同时把醋酸-水的比热与组成与温度进行了关联,并利用最小二乘法回归出所提方程中的参数,最后导出了一个计算Cp的多项式方程,此方程中既包含温度又包含组成,因此利用此方程可以计算醋酸-水体系在测定温度和组成下的Cp。把用该方程的计算值与实验值进行了比较,117个数据点的总绝对平均相对误差为0.54%。所提方程可应用于对苯二甲酸生产中换热器的设计及相关体系热量平衡的计算,具有实用意义。     

293.15 K到333.15 K温度下一些氨基酸及其相应基团水溶液中的偏摩尔体积研究

Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine,L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.15 K to 333.15K. These data are used to calculate the apparent molar volume V and infinite dilution apparent molar volume V0 (partial molar volume). Data of five amino acids are used to correlate partial molar volume V0 using group contribution method to estimate the contributions of the zwitterionic end groups (NH3 ,COO-) and CH2group, OH group, CNHNHNH2 group and C6H5(phenyl) group of amino acids. The results show that V0 values for all kinds of groups of amino acids studied increase with increase of temperature except those for CH2 group,which are almost constant within the studied temperature range. Data of other amino acids, L-valine, L-isoleucine and L-threonine, are chosen for comparison with the predicted partial molar volume V0 using the group additivity parameters obtained. The results confirm that this group additivity method has excellent predictive utility.     

天然气汽车与化工

天然气作为一种新型的清洁汽车燃料得到了广泛关注。自20世纪30年代意大利率先采用天然气作为汽车燃料以来,天然气汽车(NGV)已经有了长足的进展,成为汽车工业发展的趋势。本文分析了各种天然气汽车的特点、发展情况和市场潜力,详细介绍了天然气作为汽车燃料的贮存技术,预见性的提出了天然气汽车发展的方向,指出了发展天然气汽车燃料尚需研究一系列的化工问题。     

振动丝法测定常压和加压下液体的黏度和密度

介绍了自行研制的高温高压振动丝黏度密度仪的构造和测定原理,并以正戊烷作为实验流体对仪器的可靠性和准确性进行了测试.测定了环己烷在323.15～413.15 K温度范围内、正辛烷在313.15～393.15 K温度范围内、苯在303.15～445.15 K温度范围内压力分别为常压和6.10 MPa、正庚烷和异辛烷在298.15～403.15 K温度范围内压力分别为常压和5.10 MPa下的黏度与密度,并分别对不同压力下的黏度、密度数据进行了关联.