间苯二甲酸/新戊二醇酯化动力学

分别根据零级、一级、二级反应动力学模型,对间苯二甲酸(IPA)和新戊二醇(NPG)直接酯化反应(反应条件:有机锡为催化剂,用量为原料总质量的0.035%,醇与酸物质的量比为1.05∶1,反应温度443.15~513.15 K)的动力学进行了研究。根据模型方程通过拟合温度以及羟基物质的量浓度对反应时间的关系曲线,得到反应动力学方程。结果表明,IPA与NPG的直接酯化反应符合一级反应动力学模型,活化能E_a为15.54 k J/mol,指前因子k_0为0.4933/min。     

甲醇酯化改性花生壳吸附水溶液中铬蓝黑

以花生壳为原料,甲醇为改性剂,制备了酯化改性花生壳吸附剂,并以其吸附水溶液中的铬蓝黑,考察了铬蓝黑的初始质量浓度、吸附时间、吸附剂粒径、温度等因素对改性花生壳吸附铬蓝黑过程的影响。分别采用拟一级和拟二级动力学模型和Langmuir,Freundlich等温式对吸附动力学和等温线进行分析。结果表明:酯化改性花生壳对铬蓝黑的吸附过程符合拟二级动力学方程,吸附平衡符合Freundlich等温方程,吸附焓变ΔH>0,反应吉布斯自由能ΔG<0,表明该吸附过程为自发进行的吸热过程。甲醇酯化改性花生壳对去除水溶液中铬蓝黑效果好,是一种具有发展潜力的吸附剂。     

对苯二甲酸与乙二醇工业酯化过程研究

分析了研究了苯二甲酸与乙二醇直接酯化过程。在实验基础上，建立了与过程操作参数直接相关的简化有效的酯化反应动力学模型和二甘醇生成副反应动力学模型；并利用特定过程的工程特殊性处理了过程中水和ＥＧ分离的设计计算。     

对苯二甲酸与乙二醇直接酯化过程工程研究

从工程角度出发分析研究了精对苯二甲酸与乙二醇直接酯化过程，建立了简化有效的酯化过程主、副反应动力学模型；模拟了工业酯化过程；并利用特定过程的工程特殊性分析了过程中水和ＥＧ的分离。     

渗透汽化-酯化反应耦联膜过程动力学模型

建立了渗透汽化 -酯化反应耦联复合膜反应器过程动力学模型及测量复合膜渗透率的方法 .该动力学模型较系统地考虑了复合膜反应器中可能影响酯化反应化学平衡移动的各种因素 .研究结果表明 ,模型的模拟结果能很好地与实验结果相吻合 .     

PTA半连续醇化反应动力学研究

根据实验数据建立了ＰＴＡ半连续酯化反应动力学模型，求得酯化反应活化能为２７３．７ｋＪ／ｍｏｌ．并对半连续酯化过程的影响因素进行了讨论．     

瓶用聚酯装置酯化段软测量模型及参数估计

为开发瓶用聚酯装置酯化段先进控制软件 ,从工程角度出发分析研究了对苯二甲酸与乙二醇直接酯化过程 ,建立了简化有效的酯化过程主、副反应动力学模型。结合无约束非线性最优化方法 ,利用现场分析数据对模型进行了参数估计和校验 ,仿真结果表明所建模型是合理和有效的     

直接酯化法合成BHBT过程主反应动力学研究

以精对苯二甲酸（ＰＴＡ）和１，４ 丁二醇（ＢＤ）为原料，以Ｔｉ（ＳＯ４）２水解物为催化剂，采用直接酯化法合成ＢＨＢＴ，对主反应进行动力学研究，分别按零级、一级反应模型处理，并求得其动力学参数，进行模型的比较和鉴别，得出在本实验范围内，一级反应更为可靠的结论。     

有机锡催化对苯二甲酸与新戊二醇反应动力学研究

本文通过实验模拟粉末涂料用聚酯树脂生产过程,研究了在所选温度范围(450.15-516.15 K)内,有机锡催化PTA与新戊二醇酯化反应,定义了羟基的质量摩尔浓度。实验数据表明以羟基的消耗速率表示的表观反应速率符合一级反应动力学方程,并求出反应动力学参数。     

聚酯(PET)反应过程研究⒇Ⅳ酯化反应过程数学模拟

通过对酯化反应器流动模型的分析结合酯化反应化学平衡、反应动力学和反应器内传质的研究建立了适用于多种工业酯化反应器的数学模型     

Determination of kinetic parameters of homogenous continuous flow esterification of monobutyl chlorophosphate in a microreactor

Synthesized by phosphorus oxychloride and n-butanol, tri-n-butyl phosphate from a three-step esterification reaction has an extensive range of applications in industrial processes. Similarly, monobutyl chlorophosphate can be obtained rapidly by mixing n-butanol and phosphorus oxychloride. In view of this, we investigated the kinetics of esterification of monobutyl chlorophosphate with a microchannel system composed of micromixer and coiled capillaries. The reaction started from mixing the phosphorus oxychloride solution and n-butanol solution in a micromixer, with temperature and residence time in a delayed loop controlled, and then quenching the solution in a container with magnetic agitation. The rate constants for the esterification reaction of monobutyl chlorophosphate were determined to be within a temperature range of 298-318 K. It was found that the reaction kinetics is second order with respect to monobutyl chlorophosphate concentration and first order to n-butanol concentration. In our research, a kinetic model was established, the values of the pre-exponential factor and the activation energy of the reaction were obtained. The reaction kinetic model can interpret the synthesis mechanism of phosphate esters well, thus playing a guiding role in process intensification of phosphate esters synthesis in the future. Additionally, our model is also valuable because it contributes to the establishment of a reaction kinetics network model for the cascade reaction to synthesize phosphate esters.     

Two step biodiesel production from Calophyllum inophyllum oil: Studies on thermodynamic and kinetic modelling of modified β‐zeolite catalysed pre‐treatment

Biodiesel is one of the alternative fuels that can help in reducing oil dependence. β‐Zeolite was modified with phosphoric acid and the modified β‐zeolite was used as catalyst for the esterification of free fatty acids (FFA) present in pinnai oil and its effect on esterification reaction was studied. Influence of catalyst amount, methanol to oil ratio and temperature on specific reaction rate was modelled using Langmuir–Hinshelwood (LH) kinetics, pseudo first order kinetics and Arrhenius equation, respectively. The kinetic constant values obtained in LH kinetics show that the adsorption capacity of FFA on catalyst surface was approximately 23 times higher than that of methanol. From pseudo first order kinetic modelling it is found that methanol to oil molar ratio of 9 gives the optimum k value. Thermodynamic studies were also performed to prove the endothermic nature of Pβ catalysed esterification reaction. © 2011 Canadian Society for Chemical Engineering     

Esterification of fatty acid over Tunisian acid activated clay: kinetic study

Tunisian acid activated clay was investigated as catalyst in the esterification of stearic acid with ethyl alcohol, carried out in a semi-continuous reactor. Kinetic study shows that the reaction is first order with respect to acid concentration. The activation energy found was 21 kJ/mol. This result suggests that the reaction process was controlled by a diffusional step. A kinetic model, giving the apparent constant rate as a function of temperature and catalyst concentration, has been established. This equation has been then successfully applied for a complex mixture of fatty acid.     

微波辅助玉米油基生物柴油制备及酯化反应动力学

以玉米油和甲醇为原料、浓硫酸作催化剂,微波辅助制备生物柴油,研究了反应时间、反应温度、催化剂体积及微波功率对玉米油酯化率的影响,在单因素实验基础上优化制备工艺,考察了酯化反应的动力学. 结果表明,微波辅助制备玉米油基生物柴油的最佳条件为反应温度72.0℃、时间17.5 min、催化剂用量为玉米油体积的8.5%和微波功率200 W,该条件下酯化率可达77.6%. 酯化反应级数为1.28,活化能Ea=1.79 J/mol,酯化反应的动力学方程为r=8.214e?1.792/RTC1.28 .     

碱减量废水残渣甲酯化反应动力学研究

为实现碱减量废水残渣有效利用,对碱减量废水残渣甲酯化反应条件与反应动力学规律进行了系统考察。论文首先考虑洗涤干燥等预处理方法对碱减量废水残渣组成的影响,然后通过改变醇酸比、初始水分含量及反应温度条件,进行了碱减量废水残渣甲酯化反应动力学实验研究。结果表明,预处理可有效去除残渣中的无机盐杂质提高对苯二甲酸纯度,但预处理会明显降低后续残渣甲酯化产物对苯二甲酸二甲酯(DMT)的收率以及对苯二甲酸(TA)甲酯化反应的转化。TA甲酯化两步反应均对温度敏感,采用典型的可逆平衡反应模型对实验数据进行拟合,得到动力学模型参数,并在此基础上对动力学模型进行检验,结果表明所建立的动力学模型是可靠的,能很好的预测各组分的浓度。研究所得可为碱减量废水残渣甲酯化工艺放大与设计提供依据。     

Mechanism and kinetics of esterification of adipic acid and ethylene glycol by tetrabutyl titanate catalyst

An eight-step mechanism of esterification reaction between adipic acid (AA) and ethylene glycol (EG) catalyzed by tetrabutyl titanate [Ti(OBu)₄] was studied in detail. The kinetic data for the esterification reaction between AA and EG catalyzed by tetrabutyl titanate [Ti(OBu)₄] were measured in the temperature range of 403 K-433 K. A second-order kinetic model was established, and the model parameters were obtained through an optimization procedure by minimizing the value differences between the simulated component concentrations in the reaction system with the experimental ones. The results demonstrate that the model is suitable for the esterification reaction between AA and EG catalyzed by tetrabutyl titanate [Ti(OBu)₄]. Furthermore, the esterification reaction rate increases with the increase of reaction temperature, concentration of catalyst and the initial reactant ratio of EG to AA.     

CONSECUTIVE ESTERIFICATION OF 1,4-BUTANEDIOL WITH ACRYLIC ACID BY HOMOGENEOUS CATALYSIS

The esterification of 1,4-butanediol with acrylic acid catalyzed by sulfuric acid in the absence of solvent was studied in a batch stirred reactor. Experiments were carried out with different acid/ alcohol mole ratios and different amounts of sulfuric acid in the temperature range 70 to 90°C and 1 atm. It was found that the esterification of 1.4-butanediol with acrylic acid is a two-step consecutive, reversible reaction and each esterification step follows a first-order rate expression with respect to each component. A kinetic model was proposed to describe such a consecutive, reversible esterification reaction catalyzed by sulfuric acid. The equilibrium constants were determined from the equilibrium concentrations of each component while the rate constants in each reaction step were calculated by correlating the experimental data with the developed kinetic model.     

Kinetics of the esterification of phthalic anhydride with 2-ethylhexanol. I. Sulfuric acid as a catalyst

The kinetics of the esterification of mono-2-ethylhexyl phthalate in the presence of sulfuric acid as a catalyst has been investigated in an isothermal semibatch reactor. The reaction appears to be first order with respect to mono-2-ethylhexyl phthalate alone and the reaction rate does not depend on the concentration of 2-ethylhexanol. The kinetic parameters have been determined.     

酯化-酯交换两步法制备生物柴油的动力学

以潲水油（WCO）为原料,探讨了酯化-酯交换两步法制备生物柴油的反应动力学。以活性炭负载硫酸铁［Fe₂(SO₄)₃/AC］为负载型催化剂,通过测定不同反应温度、不同甲醇/脂肪酸（FFA）摩尔比条件下WCO中游离脂肪酸的转化率,以此确定酯化反应的动力学控制步骤及动力学方程中的待定参数,从而建立了在实验温度范围内酯化反应的动力学方程,并根据碱催化酯交换反应机理,在简化的动力学模型基础上,推导出了WCO中甘油三酯（TG）与甲醇发生酯交换反应的宏观动力学方程。结果表明,酯化反应和酯交换反应的动力学方程在实验条件范围内都能较好地描述各自的反应过程。     

Kinetics of esterification of lauric acid with fatty alcohols by lipase: effect of fatty alcohol

Lauric acid has been esterified with some C₁–C₁₈ aliphatic alcohols by a commercial lipase, Lipolase 100 L, using isooctane as a solvent. When lauric acid and fatty alcohols were taken in the mole ratio 1:1, first order kinetics were observed for all the alcohols studied. The highest reaction rate was observed for n‐butyl alcohol. Lauric acid was esterified with stearyl alcohol, in varying acid to alcohol mole ratios to explain the first order kinetics of the reaction. A kinetic model for the lipase‐catalysed esterification in a biphasic organic–aqueous system has been proposed. Based on the interfacial substrate concentration, an analytical rate equation for initial rate of the reaction was derived and confirmed with the experimental data. © 2002 Society of Chemical Industry