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It is important to develop an energy- and cost-efficient method of concentrating phosphoric acid because it is widely used in several industries. Three different ceramic membranes, namely, a silicon carbide (SiC) membrane, a TiO2-coated SiC membrane, and a sandwich membrane of TiO2 between SiC, were successfully applied for the selective separation of water from spent phosphoric acid. SiC was selected as raw material, TiO2 as supporting material. The membrane was characterized by various instruments to check all parameters. Using the solution diffusion, statistical modeling of these membranes was performed and the membrane parameters, such as membrane diffusivity and mass transfer coefficient, were calculated. By reducing the porosity of the membrane, the desired separation can be improved. 相似文献
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Marzieh Bakhshi Hamid Reza Mortaheb Mohammad Hassan Amini 《Journal of surfactants and detergents》2021,24(3):491-499
Demands for phosphoric acid are growing rapidly in various industries. This has highlighted the importance of optimizing its production and purification methods. Phosphoric acid can be produced by a wet process. However, due to the presence of many organic and inorganic impurities in the wet product, purification of the resulting product is a major concern in this industry. Removal of trace metal impurities (such as magnesium, cadmium, chromium, zinc, etc.) from produced phosphoric acid in a wet process was investigated by foam fractionation in a semi-batch setup using sodium dodecyl sulfate (SDS) as the surfactant. Effects of inlet air velocity, surfactant concentration, and surfactant selectivity were investigated. The optimum air velocity and surfactant concentration were obtained as 0.020 cm/min and 0.7 g/L, respectively. At the optimum condition, the total removal efficiency and enrichment factor reached were 70.2% and 4.39, respectively, while the acid loss was 8.3%. The total metal removal efficiency was increased to 95.3% in a two-stage experimental run. 相似文献
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江成发 《高校化学工程学报》1997,11(3):249-254
在298.15k的浓磷酸水溶液中,认为存在H3PO4=H^+H2PO4^和H2PO^1+H3PO4=H5P2O8两个化学平衡。用修正的Pitzer离子相互作用模有达磷酸水溶液的过剩Gibbs自由能,推导出能精确描述浓度高达18.0mol.kg^-1的磷酸水溶液体积性质的数学模型。 相似文献
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对除草剂乙草胺生产过程中的副产品———磷酸的回收利用进行了研究 ,通过分析其性质和组成 ,设计出切合实际的回收利用方案 ,既节约了能源又减少了对环境的污染 相似文献
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综述了磷酸燃料电池中气体扩散电极的材料、电极制备方法及发展趋势。介绍了磷酸燃料电池及其技术应用的现状和前景。 相似文献
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磷酸分解磷矿石的动力学 总被引:8,自引:0,他引:8
采用间歇反应器,在反应温度60-80℃,磷酸浓度在20-40%P2O5,磷矿粒径0.138-0.7mm;搅拌速度500转/分的条件下,研究了磷酸分解上蒜磷矿的酸解反应动力学,研究表明,在上述条件下,该过程的速率控制步骤为氢离子通过Ca(H2PO4)2的固态膜向反应界面的扩散。并建立了酸解过程的动力学模型,该模型在a=0.5上显著,表观活化能Ea=10.08kJ.mol^-1。 相似文献
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湿法磷酸萃取槽防腐内衬,一直都采用厚壁防腐,其厚度在25mm以上,投资高,工期长。目前初步研究成功14mm厚的薄壁防腐内衬,经二年生产使用,光泽尚如初,比厚壁内衬节约设资35%~80%。 相似文献
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湿法磷酸中含有大量的杂质,包括Pb2 、Cr2 、SO2-4、氟以及砷等,它们影响磷酸的结晶过程,采用化学沉淀法及溶剂沉淀法相结合的方法预净化湿法磷酸,研究了各沉淀剂用量、温度、时间对磷酸预净化效果的影响.结果表明,以碳酸钡为脱硫剂预净化湿法磷酸后可以脱除95.5%的硫酸根、95.2%的砷和78%~90%的铁、铝、镁金属离子,预净化后湿法磷酸中的杂质不影响其结晶,且磷酸经过重结晶后达到了工业磷酸质量的要求. 相似文献
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对磷酸萃取料浆用立式压滤机脱水、洗涤进行了试验研究,对试验结果进行了分析,认为立式压滤机可以替代其它脱水设备对磷酸萃取料浆进行脱水处理。 相似文献
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采用磷酸电解质对铝合金板进行了阳极化处理并测试了其胶接性能,测试了阳极化过程中铝合金板的基本力学性能,观察了阳极化处理后的铝合金板的表面形貌,分析了阳极化处理后铝合金粘接副的胶接界面、拉伸剪切失效模式.结果表明,铝合金板经过酸洗、碱洗和阳极化等过程后,其破坏强度、屈服强度、弹性模量和断裂延伸率等力学性能基本保持不变.阳极化后铝合金板表面形成了一层凹凸不平、多孔结构氧化膜,胶接时胶黏剂能渗透进入该氧化膜,形成一层胶接过渡层,阳极化处理提高了铝合金粘接副之间的拉伸剪切强度,其拉伸剪切强度最大可提高1.76倍.阳极化处理后的铝合金板粘接副之间的破坏模式为混合破坏,即存在胶黏剂的剪切破坏,同时存在粘接界面的剥离破坏. 相似文献
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Phosphoric acid is an important industrial chemical. It is mainly produced by the wet process which consists of an attack of the phosphate rock by sulphuric acid leading to a complex solution containing a large number of impurities such as metal ions like Fe3+, Al3+, Mg2+, Cd2+ etc., which can effectively be recovered by solvent extraction process. In this present work a model of the liquid‐liquid extraction process is presented. It is mainly based on thermodynamics, where two different routes have been tested for the modeling of the complexation process. The method has been tested using a model system with Al3+ as the contaminant, dodecyl naphthalene sulphonic acid (HDDNSA) as the complexing agent and kerosene as the diluent. The study has also investigated the influence of various parameters such as the pH of the aqueous phase and the initial concentration of the phosphoric acid. 相似文献
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针对磷酸生产用水的特殊性,总结了大装置磷酸生产用水封闭循环使用存在的问题,并因地制宜地找到了解决此问题的方法。 相似文献
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俞政一 《硫磷设计与粉体工程》2007,(5):1-8
磷矿酸解反应并非是离子间的交换,而是功能基团之间的交换。因此,磷酸萃取过程的P2O5萃取率、磷酸及后继产品性质、磷石膏结晶晶形和过滤性能与磷矿物特性有关。影响装置生产能力的主要因素是泡沫而不是反应时间和温度;磷酸快速萃取技术的核心是提高萃取和料浆过滤系统的温度。 相似文献
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针对云天化国际红磷分公司磷酸二铵装置浓磷酸贮槽投用6年后频繁出现橡胶衬里失效导致槽体泄漏的现象,对磷酸贮槽在使用和维护中容易出现防腐失效的部位进行橡胶衬里设计结构改进。改进后的酸槽在经相同的使用时间后,橡胶防腐衬里使用状况仍良好,设计结构改进对防腐可靠性的提高明显。 相似文献
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湿法(浓)磷酸化学法脱氟净化的研究 总被引:5,自引:0,他引:5
试验研究了湿法(浓)磷酸两种化学脱氟法,即氟硅酸钾一乙醇沉淀法和氟铝酸钠沉淀法。认为,后者优于前者,比I.M.C真空蒸汽深度脱氟法更经济,更适合于中小企业。文中关键探讨了铝在脱氟过程中的机理,同时对湿法(浓)磷酸(选择性)净化做了综述。 相似文献
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In this work, three technologies are studied for the purification of phosphoric acid produced by the wet process: chemical oxidation with hydrogen peroxide, adsorption onto activated carbon, and electrochemical oxidation by boron‐doped diamond anodes. The treatment of wet‐process phosphoric acid by chemical oxidation with H2O2 as oxidizing agent can remove 75 % of the initial TOC as maximum, indicating that this wet‐process phosphoric acid contains an important amount of organics that cannot be oxidized by hydrogen peroxide under the operation conditions used. High temperatures and hydrogen peroxide/TOC ratios close to 150 g H2O2/g TOC allow obtaining the best chemical oxidation results. The adsorption onto activated carbon can remove between 40 and 60 % of the initial TOC as maximum. Adsorption times of 2 hours and activated carbon/WPA ratios close to 12 g AC/Kg WTP assure both steady state and maximum adsorption of organics. The electrochemical process is the only technique by which complete mineralization of WPA organics can be achieved. Operating at 60 mA cm–2 and at room temperature, high current efficiencies are achieved which only seem to decrease by mass transport limitations. 相似文献