丁二酮合成新工艺研究

本文用亚硫酸甲酯与２－丁酮在Ｌｅｗｉｓ酸盐－磷酸－盐酸催化体系中缩合制备丁二酮一肟,肟水解生成的丁二酮收率达到４２％,纯度达到９２％以上,工艺改进过程具有投入少、操作简单、效益突出的优点。     

丁二酮制备新工艺研究

叙述了异丁醛气相氧化制备丁二酮的一种新工艺,对气相氧化反应条件进行了试验研究,其适宜的工艺条件为：反应温度为２００℃,氧醛物质的量比为１．０５,空速为１１５０ｈ＾－１,异丁醛体积分数为１０％,产品总收率的２８％。     

甲乙酮合成丁二酮

本文介绍丁二酮制备方法,着重阐述甲乙酮与亚硝酸乙酯合成丁二酮的工艺过程,提出温度对各反应过程中的敏感作用,严格控制操作温度,是提高丁二酮收得率的主要因素。     

臭氧氧化法合成2,3-丁二酮

以乙醛为原料,经过缩合和氧化两步反应合成了2,3-丁二酮,在氧化反应时采用臭氧氧化工艺,优化工艺条件为:n(水)∶n(乙偶姻)∶n(乙酸)=1∶0.51∶0.007 5,臭氧氧化温度10℃,臭氧流速0.3 L·min~(-1),搅拌速度600 r·min~(-1),反应时间90 min;在上述条件下, 2,3-丁二酮收率为96.2%,工业合成试验的分离收率仍可达95.0%。采用熔点检测、 FTIR、~1H NMR、~(13)C NMR和质谱技术对产物结构进行了表征与确证。     

特戊酸的合成研究

以异丁醇和甲酸为原料,常压下合成了特戊酸。适宜的工艺条件为：异丁醇：甲酸：催化剂＝１：１．１：６￣７;反应温度：５５￣６０℃,产品收率可达８０％以上。     

邻碘酰苯甲酸氧化乙偶姻合成丁二酮

以邻碘酰苯甲酸(IBX)为氧化剂,对乙偶姻氧化合成丁二酮的反应进行研究。考察了影响反应的因素,得出了其优化反应条件为:邻碘酰苯甲酸与乙偶姻的物质的量比为1.2∶1,用叔丁醇作溶剂,反应温度为70℃,反应时间40 min,产率达95%。氧化剂和溶剂均可以回收利用。     

丙二醇醚合成新工艺的开发

在制备ＬＡ－２型固体催化剂的基础上开发成功的液固相固定床连续合成丙二醇醚新工艺，具有环境友好的特色。小试试验确定了反应工艺条件，在１５吨／年 规模的单管模型试验装置上进行了验证，建成了３０００吨／年丙二醇醚生产装置，工业应用获得成功。     

丁酮气相催化氧化制丁二酮

研究了丁酮气相催化氧化制丁二酮的新技术。结果表明：硅藻土作载体时,随着Ｐ２Ｏ５／Ｖ２Ｏ５比从１．６４升高到４．４,丁二桐的选择性逐渐增加到３３％左右,从４．４升高到５．６,丁二酮的选择性增加幅度较缓。五氧化二钡的含量从５％增加到１５％,转化率和选择性基本稳定。添加Ｋ２Ｏ或Ｎａ２Ｏ后,丁二酮的选择性上升１０％左右,而乙酸的选择性下降。     

丁酮气相催化氧化制丁二酮

研究了丁酮气相催化氧化制丁二酮的新技术。结果表明 :硅藻土作载体时 ,随着P2 O5 /V2 O5 比从 1 6升高到 4 4 ,丁二酮的选择性逐渐增加到 33%左右 ,从 4 4升高到5 6,丁二酮的选择性增加幅度较缓。五氧化二钒的含量从 5%增加到 1 5% ,转化率和选择性基本稳定。添加K2 O或Na2 O后 ,丁二酮的选择性上升 1 0 %左右 ,而乙酸的选择性下降。     

微波辐射三氯化铁氧化乙偶姻合成丁二酮

微波辐射下以三氯化铁为氧化剂,对乙偶姻氧化合成丁二酮的反应进行研究。考察了影响反应的因素,得出了其最佳的反应条件为:乙偶姻与三氯化铁的物质的量比为1∶1.3,用水作溶剂,400 W微波辐射10min,产率达81.41%。     

STEADY STATE SIMULATION OF A PACKED BED REACTOR FOR THE PARTIAL OXIDATION OF METHANOL TO FORMALDEHYDE. INFLUENCE OF DIFFUSIONAL PHENOMENA AND CATALYST ACTIVITY DISTRIBUTION WITHIN THE PELLETS

The scope of this work is to present a real case in which reactor performance predicted theoretically, avoiding the numerical integration within the particle, is compared with experimental findings. The influence of realistic catalytic activity distributions are also studied since minimum extra efforts are needed with the procedure presented in this contribution. The partial oxidation of methanol in a tubular catalytic reactor, studied by Windes et al. (1989), giving rise to formaldehyde and carbon monoxide as main reaction products, was used as example for the application of our procedure. Both, inter and intraparticle, diffusional limitations were taken into account. Experimental data and theoretical predictions along the reactor were compared in terms of outlet conversion and temperature profiles showing a fairly good agreement which gives support to the procedure developed in this contribution to predict reactor performance. Furthermore, the effect of different realistic activity distribution function was simulated and its influence on the reactor performance is shown. The obtained results are discussed and some interesting conclusions are withdrawn.     

固定床电化学反应器研究进展

本文主要就垂直到固定床电化学反应器研究的进展情况进行了综述，阐明了该类反应器开发、设计及操作优化的关键，指出了研究方法及研究方向．     

OPTIMAL DESIGN FOR THE RESIDUAL OIL HYDRODEMETALLATION IN A FIXED BED REACTOR

A restricted diffusion model was used to investigate the optimal design for the residual oil hydrodemetallation in a fixed bed reactor. Based on the total lifetime activity, the optimal catalyst pore sizes and their corresponding optimal division locations in the bed were determined. The results indicate that the total amount of demetallation could be significantly improved by using a multi-layers reactor and the nonuniform activity catalysts. In addition, the influence of the Thiele modulus on the optimal designs were illustrated.     

固定床反应器进行n级反应的飞温判据

本文以一级反应系统参数敏感性理论为依据，给出ｎ级反应系统以ε为扰动参数的临界热点温度表达式，内插得到该系统的飞温判据。结果表明：反应级数越大，系统抵抗外部环境干扰的能力越强，安全操作区域越大，参数敏感区域越小。     

Fixed‐Bed Multi‐Tubular Reactors for Oxidative Dehydrogenation in Ethylene Process

An industrial‐scale reactor for ethylene production was modeled using the oxidative dehydrogenation of ethane (ODHE) in a multi‐tubular reactor system, examining a variety of parameters affecting reactor performance. The model showed that a double‐bed multi‐tubular reactor with intermediate air injection scheme was superior to a single‐bed design, due to the increased ethylene selectivity while operating under lower oxygen partial pressures. The optimized reactor length for 100 % oxygen conversion was theoretically determined for both reactor designs. The use of a distributed oxygen feed with a limited number of injection points indicated a significant improvement on the reactor performance in terms of ethane conversion and ethylene selectivity. This concept also overcame the reactor runaway temperature problem and enabled operations over a wider range of conditions to obtain enhanced ethylene production.     

床层与颗粒直径比小的固定床反应器径向空隙率分布

采用旋转法测定了床径比小的固定床反应器中的径向空隙率分布。填充颗粒为球形、圆柱形。填充形式为紧密填充。通过对实际数据的拟合建立了描述其径向空隙率分布的数学模型。     

流化床反应器过程强化技术

Fluidized beds enable good solids mixing, high rates of heat and mass transfer, and large throughputs, but there remain issues related to fluidization quality and scale-up. In this work I review modification techniques for fluidized beds from the perspective of the principles of process intensification (PI), that is, effective bubbling sup-pression and elutriation control. These techniques are further refined into (1) design factors, e.g. modifying the bed configuration, or the application of internal and external forces, and (2) operational factors, including altering the particle properties (e.g. size, density, surface area) and fluidizing gas properties (e.g. density, viscosity, or velocity). As far as two proposed PI principles are concerned, our review suggests that it ought to be possible to gain improve-ments of between 2 and 4 times over conventional fluidized bed designs by the application of these techniques.     

Acetaldehyde dimethylacetal synthesis with Smopex 101 fibres as catalyst/adsorbent

The synthesis of dimethylacetal using acetaldehyde and methanol as raw material in the presence of Smopex 101 fibres as catalyst and adsorbent in batch reactor and in a fixed bed adsorptive reactor, respectively, was studied. In the batch reactor the determination of thermodynamic and reaction kinetics data for acetalization reaction was presented. A kinetic model based on a pseudo-homogeneous rate expression using activities was proposed to describe the experimental kinetic results. The dynamic binary adsorption experiments were carried out in the absence of reaction at 293.15 K in a laboratory scale column. The experimental results of the adsorption of binary non-reactive mixtures are reported and used to obtain multi-component adsorption equilibrium isotherms of Langmuir type. The mathematical model was proposed to describe the adsorptive reactor dynamic behaviour. The experimental results obtained for the reaction and regeneration experiments were compared with the model proposed. Model equations were solved by orthogonal collocation on finite elements (OCFE) implemented by the PDECOL package, using the measured model parameters and was validated for both reaction and regeneration steps.