湿法磷酸萃取制备磷酸二氢钾的研究

开发了以湿法磷酸和氯化钾为原料,利用有机溶剂萃取法制备高品质磷酸二氢钾的新工艺。研究了溶配过程氯化钾的加入量对脱氟的影响和萃取时间、萃取温度、相比、氯化钾与磷酸物质的量比等对磷酸、盐酸的萃取率与硫酸根、铁离子、氟离子等杂质的脱除率的影响;以及洗涤相比对五氧化二磷洗涤率的影响,确定了适宜的工艺条件。实验表明：在萃取温度为 60 ℃、萃取时间为 30 min、相比为3.0、氯化钾与磷酸物质的量比为1.0、洗涤相比为12的条件下,五氧化二磷收率可达95.98%以上,产品磷酸二氢钾纯度可达96.75%以上。     

Study on removal of Fe3+ from sodium dihydrogen phosphate by emulsification solvent extraction

Wet-process phosphoric acid (WPA) is gradually paid attention to in recent years. However, there are some undesirable impurities (Fe³⁺, Al³⁺, Mg²⁺) in WPA, which will degrade the quality of sodium dihydrogen phosphate (NaH₂PO₄) products. To get the superior grade NaH₂PO₄, the WPA should be purified. Enhancing the pH of the solution, often to 4, can remove most of the metal ions, but there is still some Fe³⁺ which has great effect on the NaH₂PO₄ crystal products, seem to be irregular long strips. Therefore, before the neutralized NaH₂PO₄ solution is concentrated, the Fe³⁺ must be removed.The emulsification extraction of Fe³⁺ from sodium dihydrogen phosphate (NaH₂PO₄) solution by di(2-ethylhexyl)phosphoric acid (D2EHPA) is investigated. The good extraction efficiency of Fe³⁺ with D2EHPA from NaH₂PO₄ solution by emulsification extraction is verified. Meanwhile, to study the advantages of the emulsification extraction process, the major influencing factors, such as the D2EHPA volume fraction, the phase volume ratio, the initial pH of NaH₂PO₄ solution, the stirring time and agitation speed on the extraction efficiencies of Fe³⁺, are studied, and the optimal process conditions are obtained. The results of extraction experiments from practical NaH₂PO₄ solution show that superior grade NaH₂PO₄ can be obtained by three stages of extraction under appropriate condition.     

乳化萃取法脱除Mg2+制备工业级磷酸二氢钠的研究

本文以高效的二(2-乙基己基磷酸)(D2EHPA)为萃取剂,采用乳化萃取技术来提取NaH2PO4溶液中的Mg2+杂质,通过考察萃取剂浓度,水相溶液pH值,相比(水相:有机相),乳化速度等对萃取Mg2+萃取率的影响,求得适宜工艺条件:D2EHPA体积分数:75%,相比(A/O):2∶1,起始NaH2PO4溶液pH值为4,搅拌速度:3000r.min-1;实验结果表明,在适宜工艺条件下,经过三级萃取,可制取工业级NaH2PO4。     

萃取法制备工业级磷酸二氢铵-萃取剂的反萃取研究

本课题以高效的2-乙基己基磷酸(D2EHPA)为萃取剂,采用溶剂萃取法来提取MAP溶液中的Mg2++杂质,从而实现生产高品质MAP的目的;但是实现其产业化的难点之一,就是反萃取剂的选择,而在选择反萃取剂时关键是实现络合物D2EHPA-Fe3+的有效分离,因为络合物D2EHPA-Fe3+是非常稳定的,而且Fe3+的富集能使萃取剂老化.因此,选择有效的反萃取剂来实现D2EHPA的循环回收利用是非常有必要的.以H2SO4+添加剂A为反萃取剂,通过考察反萃取剂浓度,相比,反应温度,反应时间,搅拌速度等对反萃取Fe3+反萃取率的影响,求得最佳工艺条件为H2SO4浓度:4mol· L-1,反应温度45℃,相比为1∶1,搅拌速度550r· min-1,搅拌时间0.5h.     

湿法磷酸选择性除杂制工业级磷酸二氢铵

以湿法磷酸为原料, 通过氟化钠选择性沉淀金属离子, 使其以NaMgAl（F, OH）₆·H₂O和XMgAlF₆（X=Na ⁺、K ⁺、NH₄ ⁺）非含磷沉淀析出, 再通氨中和制得工业级磷酸二氢铵。分析了氟化钠加入量对杂质脱除（Na、K、Al、Mg、Fe和Ca等金属阳离子）及液相氟残留的影响, 结果表明氟化钠与磷酸质量比（m_NaF/m）为2.5%时, 效果较好, 此条件下制得的磷酸二氢铵纯度和五氧化二磷收率分别达到98.53%和86.2%。     

用湿法磷酸制工业磷酸二氢铵工艺综述

综述用湿法磷酸制工业磷酸二氢铵的几种工艺,包括传统化学法工艺、改进化学法工艺、化学净化与溶剂萃取联合除杂质工艺、湿法磷酸净化工艺、化学净化与溶剂萃取相结合工艺、萃取盐酸法工艺,介绍各工艺的生产流程,分析各工艺优缺点。建议厂家根据实际情况选择合适的工艺。     

溶剂萃取法净化萃余酸制磷酸二氢钾

 研究了以氯化钾和湿法磷酸净化后的萃余酸为原料,利用正丁醇为萃取剂回收萃余酸中湿法磷酸制备磷酸二氢钾的新方法。研究了正丁醇含水量、萃取时间、萃取温度及萃余酸用量等因素对产品产量的影响,确定了适宜的工艺条件。实验结果表明,优化的工艺条件为：m（萃余酸）∶V（正丁醇）为127.4 g/L、m（水）∶V（正丁醇）为95 g/L、温度为30 ℃、萃取时间为60 min、m（氯化钾）∶V（正丁醇）为26.075 g/L。本研究提供了一种回收利用萃余酸的经济、简单的方法。     

湿法磷酸萃取制取高品质磷酸二氢钾工艺研究

磷酸二氢钾在当前的磷酸盐工业中具有重要的实用价值,其应用涉及到工业、农业、医药以及食品等多个行业。以尽可能低成本的原材料与更简易的工艺流程来生产具备更高品质特性的磷酸二氢钾为时下所需。以湿法磷酸与氯化钾为原料,进行了有机溶剂萃取法制备磷酸二氢钾的工艺研究。研究内容包括：在溶配过程中氯化钾与磷酸物质的量比对氟离子脱除率的影响;氯化钾与磷酸物质的量比、反应时间、反应温度以及萃取相比对萃取率及杂质脱除率的影响;不同洗涤相比对五氧化二磷洗涤率的影响;反萃取以及磷酸二氢钾浓缩结晶的相关工艺。通过实验确定湿法磷酸萃取制取高品质磷酸二氢钾适宜工艺条件：反应温度为60 ℃,反应时间为30 min,氯化钾与磷酸物质的量比为1.0,洗涤相比为12。在此工艺条件下所得磷酸二氢钾产品纯度高达97%,达到磷酸二氢钾农用级优等品标准的要求,同时五氧化二磷回收率可达到96%。     

铝及铝合金化学抛光磷酸废液制备磷酸二氢铵研究

提出了以铝及铝合金化学抛光磷酸废液为研究对象有效回收磷资源制备工业级磷酸二氢铵（MAP）的工艺方法。实验结果表明,将原废液稀释至质量浓度为95 g/L,反应温度为80 ℃,氨水中和除杂终点pH为4左右,除杂反应时间为1 h,将过滤液用氨水二次调节pH至7~8后蒸发浓缩,浓缩液加入纯度较高的磷酸废液回调pH至4~5,冷却结晶后85 ℃烘干得到MAP产品,产品经主含量、XRD分析,结果显示各项指标均符合HG/T 4133—2010《工业磷酸二氢铵》一级产品标准的要求。     

Fractionation of Soybean Globulins Using Ca<Superscript>2+</Superscript> and Mg<Superscript>2+</Superscript>: A Comparative Analysis

The substitution of CaCl₂ by MgCl₂ was undertaken in Deak’s two-step process of separating the soybean 11S and 7S globulins, aiming at higher purities and lower phytic acid (PA) contents of recovered protein fractions. The effects of pH and the addition of NaCl were also evaluated. Compared with CaCl₂, MgCl₂ reduced the PA content of the 11S-rich fraction by 63–71% but increased that of the 7S-rich fraction by 14–28%, depending on pH. Correspondingly, more Ca²⁺ was recovered in the 11S-rich fraction, while more Mg²⁺ co-precipitated with the 7S-rich fraction. NaCl increased the purity of the 11S-rich fraction and reduced its PA content, but the purity of the 7S-rich fraction was reduced by using 50–100 mM NaCl. Lowering pHs from 6.4 and 4.8 to 5.6 and 4.0 in the two precipitation steps increased the yield of both fractions. The optimized fractionating procedure was as follows: the 11S-rich fraction was precipitated at pH 5.8 by using 5 mM MgCl_2, 10 mM NaHSO₃ and 20 mM NaCl, followed by the precipitation of the 7S-rich fraction at pH 4.5. The new method provided both fractions with satisfactory protein yields (22% for 11S and 16% for 7S), purities (88% for 11S and 80% for 7S) and PA contents (0.356% for 11S and 0.882% for 7S).     

甲醇沉淀法净化湿法稀磷酸制磷酸氢二铵

介绍了甲醇沉淀法净化杂质含量较高的湿法稀磷酸(五氧化二磷质量分数25.71%)制备高品质磷酸氢二铵(DAP)的方法.详细研究了碳酸氢铵用量、甲醇用量、反应温度及反应时间对湿法稀磷酸中杂质去除率和五氧化二磷损失率的影响.得到了优化的工艺条件:碳酸氢铵用量,即氮、磷物质的量比为0.25～0.50;甲醇用量,即甲醇与磷酸质量比为4;反应温度65℃,反应时间1.25～1.50 h.用净化后的湿法稀磷酸制备出了18-46-0规格的DAP.新方法为利用中低品位磷矿制备高品质肥料磷酸氢二铵提供了一条可行的途径.     

湿法磷酸净化的萃余酸联产磷酸二氢铵和磷酸氢二钠

湿法磷酸净化及滴灌施肥技术是近年来推广应用的先进技术.湿法磷酸净化技术可大幅度节能,而滴灌施肥可达到节水及高效吸收肥效的目的.提出了用湿法磷酸净化装置副产的萃余酸制滴灌磷酸二氢铵(MAP)和工业级磷酸氢二钠(DSHP)的工艺方案.将滴灌MAP和DSHP的生产结合起来,既充分利用了萃余酸中的钠离子,又克服了萃余酸不能单独生产滴灌MAP的不足,同时生产两种产品可降低成本.该联产工艺的特点在于用生产滴灌MAP后的母液来生产DSHP.实验证明该工艺合理可行,可生产出高品质的滴灌MAP和DSHP,而且生产成本低,有较大的市场竞争力.     

Removal of iron from Cr-electroplating solution by extraction with di(2-ethylhexyl)phosphoric acid in kerosene

The extraction of iron(III) from aqueous sulphate solution was studied using di(2-ethylhexyl)phosphoric acid (HA) mixed with kerosene. Distribution ratios were investigated as a function of the concentration of sulphuric acid, extractant, metal, hydrogen ion as well as the phase ratio and loading capacity of the extractant. The extracted iron species was suggested as [Fe(HA₂)₃] and the extraction constant was found to equal (9.1 ± 0.5) × 10². The thermodynamic functions calculated from the temperature dependence data referred to the endothermic nature of the extraction process. The method of extraction was successfully applied to remove the iron from the chromium electroplating solution giving purification percent of about 97.5%.     

Effects of co-ion initial concentration ratio on removal of Pb<Superscript>2+</Superscript> from aqueous solution by modified sugarcane bagasse

A modified sugarcane bagasse (SCB) fixed bed column was used to remove Pb²⁺ from aqueous solution. To determine the optimal condition for Pb²⁺ separation, Ca²⁺ was chosen as the model interfering ion, and effects of Ca²⁺ and Pb²⁺ initial concentration ratio (C ₀ ^Ca : C ₀ ^Pb ) on the adsorption of Pb²⁺ were investigated. Results showed that adsorption amount ratio of Ca²⁺ and Pb²⁺ (q _e ^Ca : q _e ^Pb ) had a good linear relationship with C ₀ ^Ca : C ₀ ^Pb . Mass ratio of Pb²⁺ absorbed on the modified SCB was higher than 95% at C ₀ ^Ca : C ₀ ^Pb <1.95, illustrating that Pb²⁺ could be selectively removed from aqueous solution. To verify that, simulated waste water containing co-ions of K⁺, Na⁺, Cd²⁺ and Ca²⁺ was treated, and results showed that the equilibrium amount of Pb²⁺, K⁺, Na⁺, Cd²⁺ and Ca²⁺ adsorbed was 134.14, 0.083, 0.058, 1.28, and 1.28mg g^?1, respectively, demonstrating that the modified SCB could be used to remove Pb²⁺ from aqueous solution in the investigated range.     

湿法磷酸生产磷酸二氢钾杂质净化率研究

采用批量实验研究了结晶法净化湿法磷酸与氯化钾复分解反应生产磷酸二氢钾新工艺各阶段杂质的净化率。结果表明 :该工艺不同阶段对杂质有不同脱除效果 ,利用该工艺生产的磷酸二氢钾能够达到HG2 32 1-92标准     

工业净化磷酸生产磷酸二氢钾的工艺技术研究

研究以工业净化磷酸和氢氧化钾为原料,中和法生产工业级磷酸二氢钾的工艺路线。结果表明:中和反应料液密度需控制在1.33~1.35 g/m L(温度(80±2)℃),浓缩后的混合料液密度应控制在1.32~1.34 g/m L(温度(55±2)℃),结晶终点温度为40~45℃,母液循环利用不会影响磷酸二氢钾的产品质量。     

磷酸三丁酯和二异丙醚溶剂萃取 体系净化湿法磷酸的研究

以磷酸三丁酯（TBP）与二异丙醚为溶剂,采用溶剂萃取法净化湿法磷酸。研究了萃取剂中TBP体积分数、相比、萃取时间、搅拌转速、反萃取剂加入量对湿法磷酸净化效果的影响,确定了TBP与二异丙醚混合溶剂体系净化湿法磷酸的工艺条件。适宜工艺条件：萃取剂组成为TBP与二异丙醚体积比为1∶1,有机相与水相的体积比为 4∶1,萃取时间为25 min,搅拌转速为300 r/min,反萃取剂加入量为萃取相体积的20%。在此条件下,TBP与二异丙醚萃取体系对金属阳离子和氟离子有较好的分离能力。     

Efficient manganese luminescence induced by Ce<Superscript>3+</Superscript>-Mn<Superscript>2+</Superscript> energy transfer in rare earth fluoride and phosphate nanocrystals

Manganese materials with attractive optical properties have been proposed for applications in such areas as photonics, light-emitting diodes, and bioimaging. In this paper, we have demonstrated multicolor Mn²⁺ luminescence in the visible region by controlling Ce³⁺-Mn²⁺ energy transfer in rare earth nanocrystals [NCs]. CeF₃ and CePO₄ NCs doped with Mn²⁺ have been prepared and can be well dispersed in aqueous solutions. Under ultraviolet light excitation, both the CeF₃:Mn and CePO₄:Mn NCs exhibit Mn²⁺ luminescence, yet their output colors are green and orange, respectively. By optimizing Mn²⁺ doping concentrations, Mn²⁺ luminescence quantum efficiency and Ce³⁺-Mn²⁺ energy transfer efficiency can respectively reach 14% and 60% in the CeF₃:Mn NCs.     

复盐结晶法生产磷酸二氢钾结晶动力学研究

研究了用三聚氰胺结晶法由湿法磷酸生产磷酸二氢钾的结晶动力学过程。考察了搅拌、振动、杂质对结晶过程的影响及不同降温速率对结晶习性的影响,拟合并给出结晶动力学方程,采用差热分析和热重分析仪测试了结晶产品的脱水特性。     

结晶法净化湿法磷酸生产磷酸二氢钾研究

研究了三聚氰胺结晶法净化湿法磷酸复分解生产精细磷酸二氢钾工艺中磷酸三聚氰胺与氯化钾反应生产磷酸二氢钾的工艺条件。采用二次正交组合实验设计，对反应过程中反应温度，反应时间，搅拌速度，氯化钾用量，氯化钾初始浓度等诸因素的一次作用，二次作用及交互作用对五氧化二磷转化率的影响进行了研究，得到了适宜的工艺条件，所得磷酸二氢钾达到HG2321－91质量标准。