椰油甲酯中压加氢制脂肪醇动力学研究

使用装有20mL催化剂的固定床反应器,在反应温度515K～533K、反应压力4 5MPa～9 0MPa、椰子油甲酯流量8 4mL·h-1～21 6mL·h-1及氢气标准流量100L·h-1～190L·h-1的反应条件下,采用均匀设计方法,安排了实验全过程。通过对实验取得的一系列椰子油甲酯加氢制脂肪醇转化率试验数据,根据化学反应方程式和滴流床反应器模型进行了逐步回归数理统计分析处理,确定了反应动力学参数,建立了反应动力学模型,得出由转化率表示的动力学方程。得到的结论是在实验条件下甲酯中压催化加氢制脂肪醇反应为滴流床型式,滴流床指数0 426,反应级数2级。     

铜基催化剂结构对烯醛滴流床和固定鼓泡床加氢效果的影响

采用共沉淀法制备了不同组成的铜硅、铜铬和铜锌复合氧化物催化剂。利用X射线衍射（XRD）、氢气程序升温还原（H2-TPR）、氮气物理吸附（BET）和正丁胺电位滴定法等测试手段对制备的铜基复合氧化物催化剂的物化性质和孔结构进行了表征。考察了3种不同组成的铜基复合氧化物催化剂在滴流床和固定鼓泡床反应器中催化2-丙基-2-庚烯醛加氢的效果。结果表明：3种铜基复合氧化物催化剂的铜晶粒大小、表面酸碱性差异与催化2-丙基-2-庚烯醛加氢性能未呈现任何正向相关关系;具有丰富大孔的催化剂采用固定鼓泡床反应器催化烯醛加氢的效果优于采用滴流床反应器。     

不对称合成(R)-2-羟基-4-苯基丁酸乙酯的动力学

采用10,11-二氢辛可尼定修饰的Pt/Al2O3催化体系,不对称加氢合成(R)-2-羟基-4-苯基丁酸乙酯,研究了各因素影响反应速率和光学收率的一般规律.根据推测的机理,建立了未修饰体系中加氢反应的本征动力学模型,结合实验数据选定了较佳的模型.假设不对称加氢反应总速率包括反应物在催化剂表面修饰位上和未修饰位上两部分的加氢速率,建立了不对称加氢的动力学模型,经拟合得到参数并进行了验证和讨论.     

催化裂化轻汽油中烯烃加氢反应宏观动力学

基于流化催化裂化(FCC)轻汽油(初馏点-358 K)中所含烯烃组分的性质,将其划分为4个集总,采用管式滴流床反应器,在压力0.5-2 MPa、反应温度353-413 K、液体空速2.5-7.5 h-1的条件下,对烯烃在镍加氢催化剂上的加氢反应进行宏观动力学研究.实验结果显示:n-C4＝,n-C5＝,i-C5＝,n-C...     

不对称催化合成(R)-2-羟基-4-苯基丁酸乙酯

用Pt—Cinchona生物碱体系催化加氢合成(R)-2-羟基-4-苯基丁酸乙酯。进行了催化剂的制备和比较研究,并考察了修饰剂用量、2-氧代-4-苯基丁酸乙酯的初始浓度、反应氢压和温度对转化率和(R)-2-羟基-4-苯基丁酸乙酯得率的影响,得到了适宜的反应条件,在此条件下产物中(R)-2-羟基-4-苯基丁酸乙酯得率可达70％以上。实验结果表明,本研究中不对称加氢速率与光学收率呈良好线性关系,对研究不对称合成反应的规律有一定的意义。     

滴流床反应器处理有机废水的研究进展

介绍了滴流床反应器催化湿式氧化处理有机废水的发展概况和工艺特点,对滴流床反应器的主要影响因素,反应动力学和反应器数学模型等方面的研究现状进行了综述。     

其他

吉林石化分公司研究院滴流床反应器获国家专利由吉林石化分公司研究院与大连理工大学共同研制的滴流床反应器 ,近期获国家实用新型专利 (专利号 :0 2 2 382 84 4 )。这种滴流床反应器为气固液三相反应器 ,一般为绝热式 ,在液相加氢中应用较多。对于列管式滴流床反应器 ,由于设     

Ni—Mo／TiO2-Al2O3催化剂上柴油加氢脱硫反应动力学研究

以混合柴油为原料,采用高压滴流床反应器,在反应温度280—360℃、氢分压5-7MPa、氢油体积比300～900、液时空速1—6h。的条件下,考察了柴油在Ni-Mo／TiO2-Al2O3催化剂上的加氢脱硫反应规律,并建立了柴油加氢脱硫经验型模型。采用Levenberg—Marquard优化方法,对实验数据进行回归,确定了反应动力学模型中的有关参数,得到的反应级数为2．9,加氢脱硫反应的表观活化能为143613J／mol,同时得到了在实验条件范围内Ni—Mo／TiO2-Al2O3催化剂上柴油的加氢脱硫动力学方程。经检验,模型计算结果与实验数据吻合良好。     

Pd-Ni/δ-Al_2O_3应用于四氢苯酐选择性催化加氢制六氢苯酐

采用δ-Al_2O_3为载体,浸渍法制备了系列Pd-Ni/δ-Al_2O_3催化剂,在滴流床反应器中,在温度80~120℃,压力3.0~5.0 MPa,氢油比3 000∶1(物质的量比)条件下,四氢苯酐(THPA)催化加氢制备六氢苯酐(HHPA)为探针反应,实验结果显示6%Ni-2%Pd/δ-Al_2O_3催化活性最高。采用δ-Al_2O_3负载型Pd、Ni二元金属催化剂,适当降低催化剂活性,加大氢气分压,有效提高了目的产物HHPA选择性和收率。氢气分上、中、中下三个位置,进入滴流床反应器,反应布局更加均匀可控,减少副反应发生。催化加氢为放热反应,加大反应器内氢气的内循环速度,氢气作为载热体,及时转移反应热,可以有效避免局部过热现象,减少副反应的发生。在温度180~230℃,压力为-0.098 MPa条件下,减压精馏,得到HHPA的纯度为99.5%,产物总转化率和收率分别为97.3%、84.1%。     

滴流床反应器内脉冲流宏观流体力学的特性参数

引　言在石油化工工业的加氢处理中 ,滴流床反应器常操作在接近脉冲流流型区域[1] .脉冲流下气液流速都比较高 ,所以该操作方式适合催化剂活性高、反应速率快的反应[2 ] ,而且气液流量大有利于强放热反应的反应热从反应器移出。流体力学参数如脉冲速度、脉冲频率、持液量、气液分布、压力降等对于该类反应器的工业设计及操作具有很重要的意义 .Ｓａｔｏ等[3] 较早地对脉冲流的特性进行过定性的实验研究 .Ｂｌｏｋ等[4 ] 以及Ｔｓｏｃｈａｔｚｉｄｉｓ等[5] 通过电导法也对脉冲流宏观特性进行过研究 .本文用不同的实验方法对滴流床反应器内脉…     

芳烃催化加氢交叉流反应器模型

提出了一种抗硫中毒的芳烃加氢催化反应器模型,称之为交叉流反应器模型,把反应物料分为两股,其中含有噻吩的乙苯物料采用轴向连续流动方式由反应器进口进入催化剂床层,而氢气由铅直导管直接进入催化剂床层中,然后与乙苯物料混合。在氢气导管出口处形成含硫乙苯浓度低而氢气浓度高的特殊区域,因而硫对催化剂的中毒效应大幅度降低,整体上提高了乙苯加氢饱和反应效率。与传统轴向混合流反应器进行比较,在相同条件下交叉流反应器具有更好的整体加氢反应性能。分别建立了交叉流反应器与传统轴向混合流反应器模型,提出了两种反应器的催化反应转化率方程;利用此转化率方程,对实验数据进行处理,得到动力学参数,模型的计算结果与实验数据相吻合,也验证了在交叉流反应器中,硫的中毒效应明显减弱。     

Kinetics and phase equilibria of competing aldolization and elimination in a three-phase reactor

Butyraldehyde was aldolized with formaldehyde over a weakly basic anion-exchange resin catalyst in aqueous solvent in a batch reactor operating at atmospheric pressure and at temperatures 50–70°C. The reaction mixture was a liquid–liquid–solid system, an emulsion, the phase equilibria of which were studied through chemical analysis of the organic and aqueous phase as well as of the mixed emulsion. Simplified rate equations were derived starting from molecular reaction mechanisms on the catalyst surface. A liquid–liquid reactor model for the fitting of the experimental results was developed on the basis of the rate equations and the phase equilibria. The model described very well the experimental data.     

丙烯氨氧化合成丙烯腈流化床反应器的模型拟合

基于反应动力学实验结果,分析考察了丙烯氨氧化反应的动力学行为,提出了关于反应转化率与目的产物收率的幂函数形式的拟合模型,藉此对某厂丙烯腈工业流化床反应器的操作数据进行了关联,在考虑反应器中气－固流动影响的前提下,建立了丙烯腈反应器的下述宏观数学模型：反应转化率Ｘ＝０．８３２５ｕ－０．１０５８Ｒ－０．０１６４ＮＨ３Ｒ０．２５０９Ｏ２ｅｘｐ（－０．７４５９＋３５９．７９／Ｔ）丙烯腈单收ＹＡＮ＝０．０８９６ｕ０．０３４２Ｒ０．２３３３ＮＨ３（５．８２４５ｅｘｐＲ１．１３３７Ｏ２－Ｒ４．７４４５Ｏ２）ｅｘｐ（－２．０６５１＋５２２．９８／Ｔ）模型拟合的相对误差小于１０％．     

分布孔大小对环流反应器内流动影响数值模拟

采用k-ε二方程模型和欧拉多相流模型,对一种气升式环流反应器内的湍流气液二相流进行了全尺寸的数值模拟研究,考察了采用具有不同大小分布孔气体分布器时反应器内气含率和流速分布的细节。模拟结果表明采用小分布孔的反应器内的平均气含率较高,气液二相接触效果较好,对于反应过程有利。计算所得的整体气含率与实测的整体气含率进行了对比,吻合较好。     

Investigation of a rotating disc reactor for acetone stripping and asymmetric transfer hydrogenation: Modelling and experiments

Asymmetric transfer hydrogenation of acetophenone with isopropanol as hydrogen donor in the presence of a homogeneous catalyst was investigated in a rotating disc reactor. Initially, acetone stripping from binary mixtures acetone-isopropanol with nitrogen as inert gas was studied, since its removal is a key issue in improving reaction performance. The reactor consisted of a stainless steel disc mounted on a horizontal shaft, accommodated in a cylindrical shell. The disc was partially immersed in the liquid phase. Its rotation generated a thin liquid film on its upper part, which could be brought in contact with a gas phase used for stripping. A mathematical model was formulated to simulate the reactor and showed good agreement with experimental data for acetone stripping. It was observed that the efficiency of acetone removal from the liquid phase increased with the gas flowrate per initial liquid volume ratio. The effect of disk rotation was found to be small when the stripping gas was introduced in the liquid bulk. The reactor model agreed well with experimental data of the asymmetric transfer hydrogenation. An advantage of the rotating disk reactor is that the hydrodynamics of the phases can be decoupled and the gas flowrate can be increased without constraints in the liquid phase, unlike conventional agitated reactors that are limited by flooding. Simulations using high stripping gas flowrate per initial liquid volume, unachievable in stirred reactors, showed significant reduction of the residence time required to achieve >99% conversion.     

搅拌管式反应器内流动特性的大涡模拟

采用实验和数值模拟的方法研究搅拌管式反应器内的混合过程,其中数值模拟采用大涡模拟的方法研究了反应器内流体的流动场,并就不同转速条件下流体的混合时间,将大涡模拟数值结果分别与标准k-ε模型的计算结果和实验测量值相比较,结果表明:管式搅拌反应器内的流动是非稳态的,具有不对称性。同时,大涡模拟方法可以预报漩涡,特别是桨叶背面的漩涡。与实验测量值相比,大涡模拟对混合时间的计算精度比标准k-ε模型计算精度高约22.8%,证明大涡模拟方法能够有效地模拟搅拌管式反应器内的流动特性。     

A mathematical model for the dehydrogenation of methylcyclohexane in a packed bed reactor

A model for the dehydrogenation of methylcyclohexane in a tubular reactor over an industrial catalyst Pt-Sn/Al₂O₃ has been established. This model takes into account the axial dispersion at the inlet of the catalytic bed reactor as well as the heat transfer at the wall of the reactor. The heat transfer at the wall is satisfactorily represented by using a heat transfer coefficient correlation for which the parameters are obtained by fitting to the experimental data. The model provides a good representation of the radial and axial temperature profiles in the packed bed and can be also used to calculate the conversion.     

Kinetic modeling of FCC process

Catalytic cracking of petroleum fractions a process termed as FCC is usually carried out in a reactor block with somewhat complicated hydrodynamic regime. The reactor block is considered as a combination of two different reactors. The riser is a near ideal plug-flow displacement of the catalyst and reaction mixture, while the main reactor vessel (separator) is considered as an ideal mixing CSTR. Temperature gradient along the plug-flow riser can vary on a linear and non-linear dependence. This is reflected by the thermal effect on the cracking products, along the altitude of the riser. Moreover, it can exert a considerable influence on the selectivity of the process in general, as characterized by the diversity of different hydrocarbon groups both in the gaseous and liquid products. The fluid catalytic cracking (FCC) is a process of conversion of a heavy oil fraction into lighter products in a catalytic fluidized reactor. The chemical composition and the structure of the feed are reflected on the catalyst's selectivity and the amount of coke deposited. It is, therefore, necessary to consider the feed type on modeling the process. Cracking reaction in the model was represented as a five-stage process. Reaction rates for the plug-flow riser and the ideal mixing separator are described mathematically in differential and algebraic forms. The model takes into account, exponential dependence of the specific reaction rate on temperature, as well as reflects the influence of the real and bulk catalyst densities, circulation rate, equilibrium and fresh catalyst's activities, reactor pressure, feed rate and unit construction. The model was developed based on a data taken from an industrial FCC unit, that were used to compute the kinetic constants and other parameters. Concrete computed kinetic parameters were compared with corresponding experimental data for adequacy. FCC process is in constant technological development with modernization of especially the riser reactor. Kinetic modeling of the catalytic FCC reactor will give a further understanding of the process and explain the complicated mechanism involved for an efficient and optimal conversion of the feed stock.     

三相强制外循环环流反应器内的局部气泡行为

为适应新兴的工艺过程，提出一种带有强制外循环的中心气升式内环流反应器。根据结构特点及流动状态不同，将强制外循环环流反应器分为6个流动区域，即环流反应器底部区、气体分布器影响区、浆液进料影响区、导流筒上行区、气液分离区和环隙区。研究了不同流动区域内的局部气泡特性。发现不同流动区域内气泡直径沿径向的分布有较大差异，倒锥形底部结构显著影响了环流气泡的数量与直径。推导出了不同流动区域内平均气泡直径的理论模型，模型结果与实验数据吻合较好。     

旋风反应器内传热的研究

研究了旋风反应器内壁与气体之间的传热过程，提出了一套数学模型，对实验数据进行关联。结果表明，模型计算结果与实验数据基本一致，计算误差一般在１０％以下。