Numerical simulation of two-phase flow and droplet breakage of glycerin-water mixture and kerosene in the cyclone reactor

A liquid-liquid cyclone reactor(LLCR)was designed to achieve mixing-reaction-separation integration during isobutane alkylation catalyzed by ionic liquids.However,studies of the droplets deformation and breakage in the kind of reactors are lacking.In this work,the research studied the velocity distribution,pressure field,and turbulent field to investigate the flow pattern and the main energy loss location in the LLCR through the computational fluid dynamics(CFD)method.The simulation results were verified by experiemnts to prove the correctness of the model.Then the deformation and breakage process of droplets,and the influencing factors of droplets breakage were studied by remodeling which was based on the tangential velocity distribution result of the three dimensional model.The three dimensional simulation results clearly showed that the pressure of the LLCR was mainly concentrated in the cone section and fluid turbulent motion was the most intense near the lateral wall.The reconstruct the results of the two dimensional model clearly showed that the deformation and breakage location of droplets were mainly occurred in the velocity boundary layer,while it was difficult to break in the mainstream region.In addition,low surface tension and high Weber number had a positive effect on droplet breakage.

High-efficiency separation and extraction of naphthenic acid from high acid oils using imidazolium carbonate ionic liquids

N-alkyl imidazolium carbonate ionic liquids were employed to separate and recover naphthenic acid from model oils.The effects of the cationic and anionic structures of ionic liquids and operating conditions on the deacidification performance were investigated.The deacidification performance of traditional organic solvents was also investigated for comparison.The results indicated that the naphthenic acid could be completely removed from the model oil with a small mass ratio of ionic liquid to oil.The extracted naphthenic acid was regenerated with a recovery of up to 92%.In addition,imidazolium carbonate ionic liquids could be successfully regenerated and recycled.The mechanism of interaction between imidazole ionic liquids and the naphthenic acid molecules were explained by Gauss calculation.

复合离子液体碳四烷基化技术开发与应用

碳四烷基化油是车用汽油的理想调和组分,其在汽油中的调和比例伴随汽油质量标准的升级而不断提升.中国石油大学(北京)从2000年开始选定氯铝酸离子液体碳四烷基化研究方向,逐步完成了催化剂研发、离子液体碳四烷基化技术开发与工业示范.研究了氯铝酸离子液体的组成、结构及其催化性能之间的关系,设计合成了兼具高活性和高选择性的复合离子液体催化剂.研究了复合离子液体催化剂的失活机理,开发了催化剂再生方案以及氯铝酸离子液体Lewis酸活性的监控方法,在中试装置上进行了2个月的长周期运行试验,初步完成了复合离子液体碳四烷基化技术的工艺开发.研发了新型的静态混合反应器与旋液分离器,设计建成了包含原料处理、烷基化反应、催化剂再生、产品分离与精制4个系统的工业装置,并获得了优异的工业运行结果.复合离子液体碳四烷基化技术实现了产品和工艺的双绿色化,有着良好的应用前景和推广价值.

基于实时直接分析质谱技术的氯铝酸及其复合离子液体分析

经氯化亚铜改性的氯铝酸复合离子液体是碳四烷基化反应的优良催化剂,具有很高的催化活性和目标产物选择性.深入解析离子液体的组成、阴阳离子的形态及改性金属对酸中心结构的影响有助于烷基化反应机理的研究及催化剂的定向设计.首先,本工作开发了实时直接分析离子化方法,实现了氯铝酸及其复合离子液体的有效电离和直接分析.其次,通过与静电场轨道阱高分辨质谱联用、同位素峰法指认、多级质谱结构解析等对离子液体组成进行了准确表征,确定了酸性阴离子的存在形态,并明确鉴别出复合离子液体中Cu(Ⅰ)-Al(Ⅲ)双金属配位中心阴离子的存在.进而,借助高能碰撞解离技术对双金属配位中心阴离子[CuAlCl5]^-和[CuAl2Cl8]^-的结构进行了解析.最后,依据质谱分析结果对复合离子液体的卓越催化性能进行了构效关系分析.本研究为Cu(Ⅰ)-Al(Ⅲ)双金属配位中心对复合离子液体优异催化活性的贡献提供了可靠依据,为深入研究复合离子液体催化碳四烷基化反应机理奠定了基础.

液液旋流分离器的数值模拟研究进展

旋流分离器是近年来发展非常迅速的液液分离设备,其主要优点是高效、节能、占地面积少且成本低,工业应用广泛。数值模拟是液液旋流分离器研发与研究的重要手段。本工作系统地介绍了目前液液旋流分离器在数值模拟中的研究进展,详细地分析了数值模拟过程中旋流分离器模型的选择、几何结构和操作参数的改变对分离效率和流场的影响及最终的评价指标,并对几何结构和操作参数改变提出了见解,对液滴破碎和聚并、旋涡的数值模拟及开发新的公式评价分离效率进行了展望。

双金属复合离子液体的结构、性质与应用

双金属复合离子液体表现出优异的催化性能,其催化效果的核心在于双金属中心的协同作用.本文在文献调研的基础上研究了双金属复合离子液体中双金属中心的作用,提出了可定量评价双金属中心的作用强度的相对分子极性指数(MPI_(r)),并筛选出最易形成双金属复合阴离子的金属盐(CuCl、AgCl、ZrCl_(4)).结合X射线吸收精细结构谱(XAFS)和密度泛函理论(DFT)揭示了双金属复合阴离子的结构与聚集机理.研究了双金属复合离子液体的理化性质(密度、黏度、电导率、玻璃化转变温度、酸性),并从微观角度讨论了理化性质变化的成因.该研究可为双金属复合离子液体在催化、分离、高性能材料制备等领域的拓展应用提供参考.

Study on reformulation of fluid catalytic cracking gasoline and increasing production of light olefins

The effects of reaction temperature,mass ratio of catalystto oil,space velocity,andmass ratio of water to oil on the product distribution,the yields of light olefins(light olefins including ethylene,propylene and butylene)and the composition of the fluid catalytic cracking(FCC)gasoline upgraded over the self-made catalyst GL in a confined fluidized bed reactor were investigated.The experimental results showed that FCC gasoline was obviously reformulated under appropriate reaction con-ditions.The olefins(olefins with C atom number above 4)content of FCC gasoline was markedly reduced,and the aromaticscontent andoctanenumber were increased.The upgraded gasoline met the new standard of gasoline,and meanwhile,higher yields of light olefins were obtained.Furthermore,higher reaction temperature,higher mass ratio of catalyst to oil,higher mass ratio of water to oil,and lower space velocity were found to be beneficial to FCC gasoline reformulation and light olefins production.

碳四烷基化流出物制冷过程中多液滴蒸发特性

复合离子液体催化碳四烷基化是生产高品质清洁汽油调和组分的新技术,流出物制冷是维持其反应温度的重要过程。为了开发新的烷基化流出物制冷工艺,本工作研究了减压条件下异丁烷液滴的蒸发特性。将单个或多个异丁烷液滴悬浮在不同热电偶上,测量液滴的温度变化,同时使用高速摄像机记录其蒸发过程,考察了最终压力、环境温度和液滴间距对液滴蒸发特性的影响。结果表明,多液滴和单液滴都包含剧烈蒸发阶段和稳定蒸发阶段。在稳定蒸发阶段,所有液滴都适用d2定律,边缘和中心液滴的蒸发速率均小于单液滴。随着最终压力增加和环境温度降低,中心液滴与单液滴的蒸发速率差异逐渐增大。当两液滴的间距增加到5.48d0时,液滴的蒸发速率逐渐接近单液滴。