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101.
A microemulsion (ME) consisting of sodium oleate, n-pentanol, n-heptane and sodium chloride (NaCl) solution was used for Mn(II) extraction. The cation exchange mechanism of Mn(II) extraction by sodium oleate (NaOL) was confirmed by the analysis of continuous variation of the NaOL concentration and the infrared spectrum. The effect of the extraction time, the cosurfactant type and volume fraction, the volume ratio of aqueous to ME (R), the initial concentration of Mn(II), temperature, pH and the NaCl concentration in aqueous phase on the extraction yield of Mn(II) were investigated. The extraction percentage of Mn(II) was up to 99% when R = 1. Both the extraction and re-extraction had good extraction efficiency. Therefore, the extraction of Mn(II) by NaCl/sodium oleate/n-pentanol/n-heptane ME is an effective approach. 相似文献
102.
Carlos Eduardo de Ara jo Padilha Juliana Chris Silva de Azevedo Francisco Canind de Sousa J nior S rgio Dantas de Oliveira J nior Domingos Fabiano de Santana Souza Jackson Ara jo de Oliveira Gorete Ribeiro de Macedo Everaldo Silvino dos Santos 《中国化学工程学报》2018,26(12):2471-2476
In this study the potential of cloud point extraction formed by a non-ionic surfactant was used in order to separate polyphenols from industrial residues of camu-camu. The effects of operational conditions of the cloud point extraction (CPE) on the polyphenol recovery and volumetric ratio were investigated. The results showed a maximum recovery of 95.71% that was obtained using 7.0 wt% Triton X-114, native pH (3.25), and 80 wt% polyphenol extract at 30 °C. The use of cloud point extraction was successful to recover the polyphenols from agroindustrial residue since it is a simple as well as of low-cost technique. 相似文献
103.
Daniel Whittaker Andreas Geist Giuseppe Modolo Robin Taylor Mark Sarsfield Andreas Wilden 《溶剂提取与离子交换》2018,36(3):223-256
Over the last decade there has been much interest in the applications of diglycolamide (DGA) ligands for the extraction of the trivalent lanthanide and actinide ions from PUREX high active raffinates or dissolved spent nuclear fuel. Of the DGAs, the N,N,N’,N’-tetraoctyldiglycolamide (TODGA) is the best known and most widely studied. A number of new actinide separation processes have been proposed based on extraction with TODGA. This review covers TODGA-based processes and extraction data, specifically focusing on how phase modifiers have been used to increase metal loading and thus enhance the operating process envelopes. Effects of third phase formation and the organic phase speciation are reviewed in this context. Relevant aspects of the extraction chemistry of important solvents (TODGA-modifier-diluent combinations) are described and their performances demonstrated by a consideration of the published flowsheet tests. It is seen that modifiers are successfully enabling the use of TODGA in actinide separation processes but to date the identification and testing of suitable modifiers has been rather empirical. There is a growing understanding of the fundamental chemistry occurring in the organic phase and how that affects extractant speciation and metal loading capacity but studies are still needed if TODGA-based flowsheets are to become an industrially deployable option for minor actinide (MA) recovery processes. 相似文献
104.
Coproduction of Ethyl Acetate and n‐Butyl Acetate by Using a Reactive Dividing‐Wall Column 下载免费PDF全文
The performance of the reactive distillation dividing‐wall column for coproduction of ethyl acetate and butyl acetate was experimentally studied. n‐Butanol and ethanol are raw reaction materials that react with acetic acid in the reaction zone to produce n‐butyl acetate and ethyl acetate, respectively. n‐Butyl acetate is not only a product, but also acts to remove water generated by the esterification reactions. The effects of various parameters, such as catalyst loading per stage, reflux ratio, liquid split and molar feed ratios, ethyl acetate/n‐butyl acetate purity, pressure drop, and total energy consumption, are investigated. Results show that ethanol could be completely converted and the products could be easily separated, which shows great industrial application potential in the coproduction of ethyl acetate and n‐butyl acetate. 相似文献
105.
Dynamic Performance of a Complex Distillation System to Separate a Five‐Component Hydrocarbon Mixture 下载免费PDF全文
Juan Gabriel Segovia Hernández Fernando Israel Gómez-Castro Eduardo Sánchez-Ramírez 《化学工程与技术》2018,41(10):2053-2065
Distillation is one of the most used separation processes in chemical industry, although it is a highly energy‐intensive operation. For multicomponent distillation, complex structures have been proposed in previous works, which may allow energy savings. Nevertheless, it is mandatory to understand the dynamic characteristics of such complex structures. In this work, the dynamic performance of a dividing‐wall‐based structure for the separation of a five‐component mixture is studied. A sensitivity analysis is performed on the structure in terms of the interlinking streams, performing a singular value decomposition analysis to selected cases with different operational conditions. The designs with the lowest energy duties also showed the best open‐loop properties. 相似文献
106.
针对雷达图像特征提取效率低、精度不高等问题,提出一种基于增强算子的污染土雷达图像特征提取方法。首先使用多尺度非均匀滤波把含有噪声与不含噪声的像素点灰度值、构成因素及像素加权灰度密度三个特征进行划分,完成雷达图像去噪。其次提出增强算子方法,将图像数据转变至图像的空间域,以此判断污染土雷达图像内是否存在对比度不高区域和细微区域。最后采用灰色关联分析计算超像素之间的相似度,运用MLS增强算子对曲面进行拟合,通过高斯曲率与平均曲率构建出特征判断准则,提高图像特征提取完整性,实现污染土雷达图像特征的精准提取。仿真结果表明,与传统方法相比所提方法计算速度较快,雷达特征提取效率较高,可大幅提升污染土雷达图像特征提取准确率。 相似文献
107.
Wang Yi-Ting Shen Jie Li Zhi-Xu Yang Qiang Liu An Zhao Peng-Peng Xu Jia-Jie Zhao Lei Yang Xun-Jie 《计算机科学技术学报》2020,35(4):724-738
Journal of Computer Science and Technology - Entity linking (EL) is the task of determining the identity of textual entity mentions given a predefined knowledge base (KB). Plenty of existing... 相似文献
108.
鹤煤公司八矿地质构造复杂、断层褶曲发育,尤其井田深部断层多,并且煤层透气性低且松软,打钻塌孔、喷孔严重,瓦斯抽放效果不好,给煤炭开采和瓦斯综合治理带来了困难。针对鹤煤公司八矿穿层钻孔瓦斯治理技术措施进行井下现场探索与研究,通过在3205底抽巷经过多次技术方案论证、实践,摸索出一套钻冲筛运一体化整套技术流程,并分析高压水力冲孔瓦斯涌出特征、有效影响半径。通过采用高压水力冲孔、振动筛选、转载装运,提高了水力冲孔效果和效率,改善了工作环境。 相似文献
109.
110.
为解决纳滤膜用于盐湖卤水镁锂分离中长时间运行后出现通量下降、膜污染和分离效率下降的问题,开展了将陶瓷超滤膜作为纳滤预处理措施用于盐湖卤水提锂合格液的中试研究。中试设在吸附提锂车间,进水为提锂工序中的合格液。结果表明,在冬天低温环境合格液浊度<50 NTU的条件下,以及在合格液浊度上升至50~170 NTU的极端进水水质条件下,陶瓷超滤膜均可在300 L/(m 2·h)的测试通量下稳定运行,过滤时间为30~50 min/周期。产水浊度稳定<0.1 NTU,优于后续纳滤系统进水要求。 相似文献