N523-TBP-磺化煤油萃取体系从饱和氯化镁卤水中萃取锂的工艺研究

进行了以20%N523-30%TBP-50%磺化煤油萃取体系从青海高镁锂比盐湖卤水中萃取锂的工艺研究。根据相比实验求得萃取平衡等温线,通过阶梯图解法确定萃取理论级数为三级,并完成了三级逆流萃取串级实验。通过对洗涤、反萃、转相工艺进行的研究,确定了全流程八级萃取工艺。经此流程,锂的萃取率达96%,反萃液中杂质含量低,萃取剂经过多次循环无溶损,萃取性能良好,萃取过程分相快,未见三相及乳化现象。     

离心萃取法卤水提硼的研究

以青海省东台吉乃尔盐湖酸化提硼母液为原料,采用CTL50-N型小流量环隙式离心萃取器,以异辛醇/磺化煤油为萃取体系萃取析硼母液中的硼。讨论了萃取剂浓度、萃取酸度、相比、流速、转速及萃取级数对萃取工艺的影响。试验结果表明,在最佳工艺参数的条件下其萃取率达到了97%以上,反萃取率在98%以上,通过酸性溶液可使硼酸浓缩到47g/L。本试验将为产业化提硼提供依据,离心萃取器在这一方面也将会有广泛的应用前景。     

t-BAMBP/磺化煤油体系萃取溶液中微量铯

铯作为一种化学性质活泼的碱金属,具有优异的光电性能,在催化、光电、磁流体发电和医药等很多领域应用广泛。本文使用t-BAMBP/磺化煤油体系对溶液中微量铯进行萃取,用盐酸进行反萃。主要考察了萃取剂浓度、O/A(萃取剂油相与溶液水相之比)、碱度、萃取时间、振荡强度、萃取温度、反萃酸的浓度和反萃时间等实验条件。发现最佳正萃条件为萃取剂浓度1 mol/L,O/A相比1∶1,碱度1 mol/L,萃取时间2 min,振荡强度200 r/min,萃取温度为20℃,反萃酸c(HCl)为0.1 mol/L,反萃时间t_2为3 min。     

D2EHPA溶剂萃取除钙研究

研究采用D2EHPA(二-(2-已基己基)磷酸)为萃取剂的溶剂萃取法,在制备高纯碳酸锶工艺中的除钙问题。考察了萃取平衡时间、稀释剂、平衡pH值、温度、水相钙离子浓度、萃取剂浓度等因素对钙萃取率的影响,并研究了反萃条件及溶剂萃取除钙过程中锶的损失率。结果表明,D2EHPA(二-(2-已基己基)磷酸)-磺化煤油体系是除钙的优良萃取体系;萃取平衡时间在1 min左右;在平衡pH值为2.3~2.7的范围内,分配系数与pH值的关系为logD=2.0985pH-5.0215,钙的饱和萃取率达到83%;萃取过程的热效应很小,萃取率与萃取剂浓度的关系为logD=1.7312logCH2A2+2.5116;萃取过程符合液体离子交换机理,萃取络合物的组成为CaA2.1.4624H2A2;在粗碳酸锶盐酸浸取并除钡、铁杂质后的溶液中,D2EHPA(二-(2-已基己基)磷酸)-磺化煤油体系对钙的一次萃取率为46.11%,锶的损失率仅为0.35%,采用逆流多级萃取,可以完全除去其中的钙,得到高纯的氯化锶溶液。     

苯并15-冠-5—离子液体体系多级逆流萃取分离锂同位素研究

锂的两种天然同位素(~6Li和~7Li)在能源、环境和国防安全等领域具有重要应用价值。以氯化锂溶液为原料,选用苯并15-冠-5和咪唑类离子液体体系对其进行了模拟逆流萃取实验,考察了多级逆流萃取过程中锂的萃取率和锂同位素分离系数的变化规律。同时,对锂同位素富集浓度和富集行为进了研究探讨。结果表明,经10级逆流萃取后,锂的萃取率和同位素分离系数有了明显提高,~6Li富集在有机相,丰度提高了0.299 6%。     

苯并15-冠-5—离子液体体系多级逆流萃取分离锂同位素研究

锂的两种天然同位素（6Li和7Li）在能源、环境和国防安全等领域具有重要应用价值。本文以氯化锂溶液为原料,选用苯并15-冠-5和咪唑类离子液体体系对其进行了模拟逆流萃取实验,考察了多级逆流萃取过程中锂的萃取率和锂同位素分离系数的变化规律,结果表明：经10级逆流萃取后,锂的萃取率和同位素分离系数有了明显提高,6Li富集在有机相,丰度提高了0.2996%,本文对锂同位素富集浓度和富集行为进了研究探讨。     

碱性体系t-BAMBP萃取微量铷及热力学函数研究

通过对4-叔丁基-2-(α-甲苄基)苯酚(t-BAMBP)萃取微量铷的性能的研究,详细考察了稀释剂、碱度和温度对萃取的影响。实验结果表明,在260#溶剂油体系中,铷的分配比较之在环己烷体系和四氯化碳体系高;强碱性环境和低温条件有利于铷的萃取。同时通过斜率法和饱和法确定了萃合物组成为RORb·ROH,并研究了萃取过程的热焓、吉布斯自由能及熵变等基础热力学性质,结果表明该萃取反应为放热反应,萃取过程熵减。     

N523-TBP混合萃取体系从盐湖卤水中萃取锂的共萃取效应、盐析效应和共存离子影响

本文研究了N523-TBP混合萃取体系从盐湖卤水中萃取锂的共萃取效应、盐析效应及共存离子影响。首先研究了FeCl3、CoCl2、NiCl2、CuCl2、ZnCl2等过渡金属氯化物盐对锂的共萃取效应,结果表明FeCl3是最佳的共萃剂,Fe/Li摩尔比为1.3时萃取效果最优。研究了卤水中KCl、CaCl2、NaCl、MgCl2、AlCl3的盐析效应,结果表明MgCl2是萃取锂天然的最佳盐析剂。研究了卤水中Na+、K+、Ca2+等共存离子对锂萃取效果的影响,结果表明锂与共存离子的分离因数顺序为βLiMg >βLiK >βLiNa >βLiCa。以上结果表明N523-TBP混合萃取体系特别适合从高镁卤水中萃取锂,但不适于从含钙较高的卤水中萃取锂。     

制备硅钢级氧化镁前驱体的原料水化研究

以青海盐湖水氯镁石为初级原料,采用喷雾热解法制备原料氧化镁,原料氧化镁通过水化制备硅钢级氧化镁前驱体氢氧化镁。原料氧化镁水化实验中对水化剂、水化温度、水化时间、液固比、搅拌速度及陈化时间对水化率、过滤速度和纯度的影响进行系统研究。采用均匀实验设计和DPS数据处理,(依次)通过建模分析、二次多项式模型回归建立数学模型,再通过各因素方差分析和总方差分析,确定了理论最优实验条件,再用理论最优条件作重复实验进行验证,最终确定了原料氧化镁的最佳水化条件。在水化温度60℃,水化时间105 min,液固比4,陈化时间4 h,水化剂1含量4.0%,水化剂2含量3.15%,洗水量4倍,搅拌速度120 r/min时,原料氧化镁的水化率达99.50%以上,得到的硅钢级氧化镁前驱体氢氧化镁纯度高、过滤性能良好。     

硼酸盐水溶液中硼物种的存在形式及影响因素

根据以往相关的研究报道,综述了含硼水溶液中硼物种的存在形式,及其与总硼浓度、溶液pH值、溶液离子强度、温度、压力等因素的关系。随着总硼浓度的提高,硼氧配阴离子的聚合度加大,在pH值较高或较低时,聚硼离子的含量较少,主要以H3BO3和B(OH)4-的形式存在;同时,指出含硼水溶液存在普遍的过饱和现象,我国含硼盐湖卤水中的硼物种可以用B4O72-的综合统计形式表示。总结了硼酸盐水溶液中各种硼氧配阴离子的FT-IR,Raman和NMR的归属。     

羟基功能化离子液体体系用于盐湖卤水提硼

溶剂萃取法是目前工业应用前景广阔的盐湖卤水提硼方法,而萃取分离的核心在于萃取剂的选择.以异辛醇、羟基功能化离子液体1-羟乙基-3-甲基咪唑双(三氟甲磺酰)亚胺盐([HOEMIm]NTf2)按体积比混合组成萃取剂,乙酸丁酯为稀释剂,对东台吉乃尔盐湖酸化卤水进行萃取提硼的实验研究.对[HOEMIm]NTf2体积分数、相比、...     

A Raman Investigation on the Boron form Occurring in Salt Lake Brine during Evaporation

Boron resources are abundant in the Da Qaidam Salt Lake of the Qaidamu basin in China,which has generated significant attention due to the presence of polyborate species in brine from this lake. In this study,Raman spectroscopy was used to investigate the existing form of boron in brine during evaporation. MgO·2 B_2 O_3-H_2 O,MgO·2 B_2 O_3-MgCl_2-H_2 O,and MgO·2 B_2 O_3-MgSO_4~-H_2 O solutions were also studied to determine the influence of boron concentration,pH,and electrolytes on the borate speciation from brine. The mononborates B( OH)_3 and B( OH)_4~-were found to be the only forms present in natural salt lake brine. Brine evaporation promoted the formation of the polyborate anions B_3 O_3( OH)_4~-,B_5 O_6( OH)_4~-,and B_6 O_7( OH)_6~(2-)and also promoted the disappearance of the B( OH)_4~-ion from brine at boron concentrations of more than 11 g/L B_2 O_3. The pentaborate ion B_5 O_6( OH)_4~-was sensitive to the solution pH and appeared only at p H values less than 8. 0. Meanwhile,the hexaborate ion B_6 O_7( OH)_6~(2-)was observed to be more dependent on the electrolyte magnesium chloride due to its special properties,such as promoting boron accumulation,lowering solution pH,and also its strong affinity for water molecules,which were all beneficial for the polymerization of borate ions in brine. Interaction mechanisms between polyborate anions during evaporation are also proposed herein. ake; evaporation; polyborate species; interaction mechanism.     

A Raman investigation on the boron form occurring in salt lake brine during evaporation

Boron resources are abundant in Da Qaidam salt lake of Qaidamu Basin. It has been given great attention for the polyborate species present in brine. In this study, the Raman spectroscopy was applied to investigate the existing-form of boron in brine during evaporation. The prepared solutions of MgO·2B2O3-H2O, MgO·2B2O3-MgCl2 -H2O, and MgO·2B2O3-MgSO4-H2O was also evaporated and recorded to study the influence of boron concentration, pH, and electrolytes on the borate speciation in brine. The mononborates of B(OH)3 and B(OH)4- were found to be the only forms present in the original salt lake brine. Brine evaporation promotes the formation of polyborate anions B3O3(OH)4-, B5O6(OH)4-, and B6O7(OH)62- and also disappearance of the B(OH)4- ion in brine with boron concentration of more than 11 g/L in B2O3. The pentaborate ion of B5O6(OH)4- was sensitive to the solution pH and found to be appeared under the pH value of 8.0. While the hexaborate ion of B6O7(OH)62- was observed more dependent on the electrolyte of magnesium chloride due to its special properties, such as promoting boron accumulation, lowering solution pH, and also the strong af?nity for water molecules, which is beneficial to the polymerization of borate ions in brine. The interaction mechanisms among polyborate anions during evaporation had also been proposed.     

从液体矿中提取硼的研究进展

评述了目前国内外从盐湖卤水、海水、气田水等含硼体系中提硼的研究方法,特别是对溶剂萃取法进行了深入的探讨与分析。认为酸化沉淀与溶剂萃取法相结合是盐湖卤水提硼最有应用前景的方法之一。     

Extraction of Cesium and Rubidium with 4-tert-butyl-2- (α-methylbenzyl) phenol from Salt Lake Brine

This work shows the extraction of cesium( Cs~+) and rubidium( Rb~+) from salt lake brine containing potassium( K~+) and magnesium( Mg~(2+)). The results show that 4-tert-butyl-2-( α-methylbenzyl) phenol( t-BAMBP) diluted in sulfonated kerosene( SK) has an excellent extraction effect. Infrared spectroscopic studies indicate that polymerize to form the dimer in the t-BAMBP when Cs~+or Rb~+were extracted. The effects of K~+,Mg~(2+),t-BAMBP concentration,the volume ratio of organic phase to aqueous phase( O/A) and the alkalinity( pH) of aqueous phase were investigated.The K~+and Mg~(2+)should be eliminated through precipitating before the extraction and separation of Cs~+and Rb~+. The optimum extraction conditions of the experimental brine were as follows: 0. 8 mol/L t-BAMBP diluted in SK,pH≥13,a phase ratio of 1: 1,and an extraction contact time of 2 min at room temperature. The optimal extraction yields of Cs~+and Rb~+were as high as 100% and 85. 8%,in addition,8. 76% of K~+was co-extracted. Further work would increase the extraction yield and selectivity of Rb~+and realize the efficient separation of Cs~+and Rb~+from brine.     

四元体系KCl-K2SO4-KBO2-H2O在298.15 K的Pitzer模型研究

在Pitzer电解质溶液理论的基础上采用两种模型计算了KCl-K₂SO₄-KBO₂-H₂O体系及其子体系的溶解度。模型I假设溶液中只有一种硼物种B(OH)₄^-,模型II假设溶液中有4种硼物种,分别对应于B(OH)₃、B(OH)₄^-、B₃O₃(OH)₄^-和B₄O₅(OH)₄^2-。模型I与模型II的溶解度计算结果接近,且与实验值吻合较好。采用模型II计算了上述体系溶液中的硼物种和OH^-的浓度。各硼物种的浓度主要受溶液中总硼浓度的影响,而很少受KCl和K₂SO₄的影响。计算结果说明在计算偏硼酸钾溶液体系溶解度时,可近似认为溶液中硼物种只有B(OH)_4...     

青藏高原高硼卤水的水化学特征及其成因

本文就青藏高原高硼卤水的分布、水化学特征、硼与共生元素的相关性及硼矿沉积的某些规律作了阐述,进而探讨了高硼卤水的成因。