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在塔径32mm,高1960mm的振动筛板萃取塔中,用叔胺N_(235)-TBP-煤油/水等三个无传质体系,进行了液泛点和塔藏量的研究.作者认为两相流过筛孔的实际相对速度,与塔板在单位时间内对单位质量液体所做的功有关,并与体系物性及板间距相关.由于这种想法,建议用A~2F~3代替常用的AF,可以较好地关联本实验数据,和较简明地反映各参数对液泛点和塔藏量的影响,得到了一个新关联式.研究结果指出:①振幅和频率对液泛点和塔藏量的影响是不同的;②分散相的选择无显著影响,③塔板开孔率和板间距是肯定有影响的.实验的振动强度及体系物性参数的范围较宽,塔板开孔率大,板间距小,并采用金属萃取广泛应用的叔胺及二(2-乙基己基)磷酸苹取剂以及煤油稀释后作为有机相.因此,本工作对推广这种塔于金属萃取将有一定的促进作用. 相似文献
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The characteristics of a staged bubble column can be described by a multi-stage backmixing model,provided: (1) Each stage can be considered as a perfect mixing reactor,and (2) The backmixing coeffi-cients do not vary with time and reactant concentrations.Experimental results indicate that the first conditionis approached under certain conditions,while the second assumption is correct.Studies were made using steady state chemical tracer method to determine the backmixing coefficientsof each plate between stages.The fluid flow through the holes of perforatcd plates is a stochastic process.From the statistical point,the experimental data could be correlated by semicmpirical equation developed.This equation can also be used to correlate the data reported by Nishiwaki for bubble column with plateshaving high percentage of opening area and large size holes between stages.Continuous oxidation of unsaturated sulfur compounds (mainly in the form of thiosulfatc and also somein polythionate form) in nickel ammonium carbonate solution were carried out in bubble columns with heightof 3400mm and diameters of 36 mm and 100mm respectively.The oxidation has to be taken in a multistagebubble column for high degree of oxidation.The axial concentration of unsaturated sulfur compoundsalong a multi-stage bubble column can be calculated from the backmixing model and the kinetic equationof oxidation.Results of calculation agree with the data taken along the column height.Equation was alsodeveloped to calculate the optimum temperatures of oxidation which agree favorably with the experimentalresults. 相似文献
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表面活性剂对微生物脱除柴油中有机硫的影响 总被引:17,自引:1,他引:16
采用假单胞菌(Pseudomonas delafieldii)菌株R-8和红色红球菌(Rhodococcus erythropolis)菌株N1-36研究了加氢精制柴油脱硫工艺,两株菌脱除柴油中有机硫的活性相近. 添加表面活性剂能提高菌株对柴油的脱硫率;当Tween80存在、搅拌转速为250 r/min时,菌株R-8最高可脱除硫含量<300 mg/L的柴油中72%的有机硫;但当硫含量超过1000 mg/L时,微生物脱硫率极低. 相似文献
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用反向胶团制备稳定ZrO2超细粉的研究 总被引:14,自引:1,他引:14
以注入法研究了金属离子及氨水在AOT-isooctane-wanter反胶团中的溶解性,用光散射技术测定了胶团的大小,用冷冻蚀刻复形技术表征了反胶团的微观结构;研究了以反胶团为基础溶液多种制备方式对粉末的影响,实验制备了Y2O3及CeO2稳定的四方相ZrO2超细粉,研究表明,将金属离子包溶于反胶团是制备良好颗粒的必要条件。 相似文献
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For the mass transfer to single drops during the stage of steady buoyancy-driven motion, experimental measurement is complicated with the terminal effect of additional mass transfer during drop formation and coalescence at the drop collector. Analysis reveals that consistent operating conditions and experimental procedure are of critical significance for minimizing the terminal effect of drop coalescence on the accuracy of mass transfer The novel design of a totally-closed extraction column is proposed for this purpose, which guarantees that the volumetric rate of drop phase injection is exactly equal to that of withdrawal of drops. Tests in two extraction systems demonstrate that the experimental repeatability is improved greatly and the terminal effect of mass transfer during drop coalescence is brought well under control. 相似文献
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配合从高Ca含钒钢渣中提钒工作,进行了Ca(VO_3)_2和NaCaVO_4在Na_2CO_3-NaHCO_3缓冲溶液中钒浸取动力学研究。实验结果表明,这两种含钙的钒酸盐的浸取动力学行为不同。Ca(VO_3)_2的浸取速率受与Na_2CO_3和NaHCO_3的平行反应控制;NaCaVO_4在所实验的范围内不与Na_2CO_3反应,而与NaHCO_3反应的浸取速率的控制步骤是HCO_3~-离子在NaCaVO_4固体表面上的化学吸附。 相似文献