用树脂回收铀矿石细菌浸出液中铀的试验研究

以相山铀矿石的细菌浸出液为对象，用717型强碱性阴离子交换树脂对细菌浸出液中的铀进行了静态和动态吸附试验，用抗坏血酸对吸附后与铀共存于树脂上的Fe³⁺杂质进行了动态淋洗试验。静态吸附试验结果表明，要提高树脂对铀的吸附容量，细菌浸出液的铀浓度应尽可能高，并应将溶液的pH值调至1.4左右，同时树脂与溶液的接触时间应尽可能长。动态吸附试验结果表明，717型强碱性阴离子交换树脂对铀有较强的吸附能力，当柱床体积倍数为206时，树脂上的铀吸附量达93.54 mg/mL。动态淋洗试验结果表明，抗坏血酸对Fe³⁺有较强的还原性，吸附后先用抗坏血酸从负载树脂上洗脱Fe³⁺，可取得良好的铀铁分离效果。     

用D301离子交换树脂分离铼和钼

研究了大孔弱碱性阴离子交换树脂D301从含大量钼、小量铼的H_2SO_4-(NH_4)_2SO_4溶液中分离铼和钼的性能。pH4—6范围内,D301对铼吸附率最大,而pH6时钼吸附率最高。二者在pH4时分离系数有最大值,β_(Re/Mo)=2277。最佳条件下纯铼的饱和吸附量为650mg/g树脂,工作吸附容量为244mg/g树脂。用8％NH_3·H_2O 10％NH_4NO_3和10％(NH_4)_2CO_3溶液分别洗脱铼和钼,二者可得到良好分离。     

一叶萩碱的提取工艺研究

为研究叶底株的实用价值,采用大孔阳离子树脂工艺提取其中的活性生物碱,一叶萩碱。在索氏提取器中使用石油醚作溶剂,提取48 h,通过大孔阳离子树脂进行交换,提取液经碱化后再用二氯乙烷萃取其活性成分一叶萩总生物碱,再经大孔阳离子树脂分离后得到了黄色化合物一叶萩碱。实验结果表明,优化的提取条件是:样品液上柱量为90 mg/m L,洗脱流速为4 m L/min,选择80%乙醇为洗脱溶剂;洗脱液流速对纯化收率影响最大,其次是洗脱剂配比,最后是上柱量。     

提纯天然VE的工艺改进

以弱碱阴离子交换树脂对天然VE浓缩液进行纯化。考察了上样量、洗脱速度与洗脱剂对分离的影响,以天然维生素E的含量和回收率为评价指标。实验结果表明,弱碱阴离子交换树脂纯化天然VE的最佳操作条件:上柱量为90mg/mL,洗脱液流速为5mL/min,洗脱剂为环己烷:乙醇(体积比)为75:25。天然VE含量可由原来的30%提高到90%以上,回收率达到80%以上。     

硅胶-聚合胺树脂在模拟硫酸镍电解液中深度净化除铜

用离子交换柱在Ni2+70g/L,Cu2+0.5～2.0g/L,pH=1～4,温度20℃～60℃的模拟硫酸镍电解液中研究硅胶-聚合胺树脂从硫酸镍电解液中深度净化除铜的过程.用H2SO4浓度分别为1.0,1.5,2.0mol/L的解析液考察树脂的解析性能.结果表明,随料液pH增大以及温度升高,树脂对铜的交换容量增大,料液Cu2+浓度对交换容量影响不大.最佳吸附条件为料液pH=4,吸附接触时间30min,温度60℃.最佳解析条件为H2SO42mol/L,解析接触时间40min.最佳工艺条件下,树脂的铜穿漏及饱和交换容量分别为0.378和0.496 mmol/mL-湿树脂,铜解析液峰值浓度可达38g/L以上.     

离子交换技术软化处理稠油污水的研究:Ⅱ大孔弱酸性树脂-密实移动床工业装置的试运行

用大孔弱酸性阳离子交换树脂在Φ2.2 m密实移动床吸附塔中对总硬度约为200 mg/L的已深度净化的稠油污水进行软化处理,其产水的总硬度可达铬黑T检不出的程度,即硬度低于1 mg/L;饱和树脂的容量按总硬度计可达140 g/L甚至更高。饱和树脂在专门设计的填充塔内进行水反冲洗、酸淋洗、碱再生以及水洗等处理后再返回吸附塔。该套装置正式连续试运行证明,所选树脂及设备软化处理上述稠油污水性能良好,操作方便;在技术上是可行的,具有明显的经济效益及社会效益。该工艺在我国属首创,值得在有关油田加以推广应用。     

螯合树脂TP207深度去除氯化钴溶液中的镍

研究了TP207树脂在氯化钴电解液中深度净化除镍工艺，考察了该树脂不同工艺条件下对镍的吸附性能。结果表明，随接触时间的增加、料液pH值减小和温度的升高，树脂对镍的交换容量增大，料液中Ni2+浓度对交换容量有影响。镍吸附最佳条件为：料液中Ni2+浓度0.05 g/L、接触时间40 min、pH值4、温度30 ℃；料液中Ni含量低于0.5 mg/L时达到深度除镍目的，满足制备5N5高纯钴产品溶液的要求，有助于实现湿法电解高纯金属的大规模工业化生产。     

大孔弱碱性叔胺型阴离子交换树脂吸附金的研究

研究在盐酸介质中 ,BK弱碱性阴离子交换树脂吸附Au的过程。结果表明 ,树脂对金的吸附性能很好 ,Au的吸附量达 910mg/g干树脂 ,饱和树脂与Au摩尔比为 1 0 7,树脂吸附选择性好 ,贱金属除Bi外吸附率都很低 ,因此可用来从大量贱金属中吸附富集Au。吸附反应活化能与生成焓变化分别为 17 15kJ/mol和 19 98kJ·mol- 1 ·K- 1 。扫描电镜与能谱、红外与拉曼光谱研究表明 ,树脂吸附Au的形态为AuCl4 - ,吸附是从表层逐渐向深层的过程     

离子交换法从含磷溶液中提取钼的研究

采用D380大孔弱碱性阴离子交换树脂从某铀矿高浓度含磷萃余水中回收钼。结果表明:吸附时间30min,每g干树脂的吸附容量为248mg;采用80g/L NaOH溶液进行解吸,解吸时间40min,钼质量浓度峰值为60~80g/L,钼和磷解吸率均大于99%,铀的解吸率超过80%。     

新型硅胶-聚合胺树脂在模拟氯化镍电解液中深度除铜

研究了新型硅胶-聚合胺复合材料树脂SP-C在模拟氯化镍电解液中深度净化除铜工艺。在Ni²⁺ 70 g/L、Cu²⁺ 0.5～2.0 g/L、pH 1～4、温度20～60 ℃的氯化镍电解液中, 考察了该树脂对铜的吸附性能, 结果表明: 随料液pH值增大以及温度升高, 铜的交换容量增大; 料液Cu²⁺浓度对交换容量影响较小; 最佳吸附条件为: 料液pH=4、接触时间30 min, 温度60 ℃。对比研究了盐酸、硫酸两种解析液, 硫酸显示出更好的解析效果, 最佳解析条件为: H₂SO₄ 2 mol/L、解析接触时间40 min。最佳工艺条件下每毫升湿树脂铜的工作交换容量及饱和交换容量分别0.453 mmol和0.540 mmol, 铜的解析峰值液浓度为28 g/L。     

CL-N235萃淋树脂富集分离金的性能与机理研究

用原子吸收法研究了在盐酸介质中N235萃淋树脂吸附金的过程。结果表明,树脂对金的吸附性能很好,金的吸附量达860mg/g干树脂,饱和树脂与金摩尔比为1.08,树脂吸附选择性好,共存金属除铋外吸附率都很低,因此可用来从大量贱金属中吸附富集金。吸附焓变化为17.56 kJ/mol.K,红外与拉曼光谱研究表明,树脂吸附金的形态为AuCl4-。     

The adsorption of precious metals and base metals on a quaternary ammonium group ion exchange resin

Adsorption tests were conducted with a quaternary ammonium group ion exchange resin to determine the equilibrium adsorption of precious- and base metals. The resin used is a macroreticular polystyrene type 1 strong base anion exchange resin. The adsorption was determined for synthetic single metal solutions as well as for multi-component solutions. The effect of the Cl⁻ concentration on the equilibrium adsorption was determined for three different HCl concentrations, i. e. 6, 8 and 10%. The effect of chloride strength in the solution was also determined for mixed and base metal solutions. Pure metals, i.e. platinum, palladium and gold, were dissolved in aqua-regia and diluted to 2000 ppm (as metal) in 4M HCl. Ruthenium, rhodium and iridium were dissolved from pure salts in HCl. A 2000 ppm base-metal solution was prepared by dissolving all the required components, including precious metals, to match an in-plant industrial base-metals solution composition. For each precious metal the equilibrium adsorption was determined for typically two solution concentrations. Data points were established by varying the amount of resin added to the solution. The equilibrium concentrations were determined by ICP analysis after 24 hours exposure using the bottle-roll technique.     

Hydrometallurgical processing of Platreef flotation concentrate

Platinum producers are evaluating hydrometallurgical process routes to extract platinum group metals (PGM) and base metals (BM) from flotation concentrate that are alternative to conventional pyrometallurgical matte smelting treatment of flotation concentrates. This approach would attract several potential benefits to the cost-effective processing of lower-grade and high-chromium concentrates. Ivanhoe Nickel and Platinum Ltd. wished to investigate this option on samples arising from their Platreef project in the northern limb of the Bushveld Complex in South Africa, from concentrate containing 1.5 g/t Pt, 2.5 g/t Pd and 0.5 g/t Au, as well as 1.5% Ni and 1.2% Cu. Other PGMs assayed rather low grades in the concentrate (Rh 128 ppb; Ru 153 ppb; Os 18 ppb; Ir 31 ppb) so the focus was on Pt, Pd and Au in this study. Some twenty-two hydrometallurgical process flowsheet variants were considered for evaluation in a testwork programme combining several conventional and proprietary unit process technologies.The testwork outcomes suggested that a hydrometallurgical flowsheet alternative to smelting (the patented Kell Process) is potentially a practical, environmentally benign and energy-efficient approach for treating low-grade Platreef concentrate with relatively low risk. This process broadly comprises selective leaching of base metals by pressure oxidation, followed by leaching of PGMs after a roasting pretreatment step shown to render PGMs and particularly Pt amenable to leaching. The process embodies separation of the value metals (PGM and base metals) into separate chloride and sulfate solution streams, respectively, and impurity elements (Fe, Al and gangue) into a tailings product. Key elemental deportments from the un-optimized process were Ni 96%, Co 94%, Cu 94%, Pt 96%, Pd 94% and Au 87%.Preliminary work indicated that further improvements in value metal recoveries, impurity separations and reagent consumptions may be gained from further optimization of the individual unit processes. Moreover, the recycle of key reagents uses existing proven technologies, rendering the process more economically and environmentally favourable. Initial assessment suggests that the Kell Process should offer both economic and environmental benefits over conventional pyrometallurgical matte smelting treatment of Platreef flotation concentrate.     

碱熔-离子色谱法测定次氧化锌中的氯离子

建立了碱溶-离子色谱法测定次氧化锌中氯离子的分析方法。采用碳酸钠半熔-水浸出方法预处理样品,阳离子交换树脂去除重金属离子,以碳酸钠(2.5 mmol/L)和碳酸氢钠(3.5 mmol/L)混合溶液作为淋洗液,离子色谱法测定样品。方法的平均加标回收率为98.60%,检出限为0.015%。本方法灵敏度高,精密度好,预处理样品简单,易于操作,适合批量样品的测定。     

The use of ion exchange resins for the treatment of cyanidation tailings part 1––process development of selective base metal elution

This work investigates the use of oxidative acid eluents for the elution of base metals from strong base ion exchange resins. Eluents composed of a mixture of H₂O₂ and H₂SO₄ were tested for eluting base metals from resins loaded with mixtures of base and precious metal cyanides. This process removed 100% of Cu and Zn loaded on the resin, without affecting the precious metal loading. It was found that copper could be removed separately from the other base metals. The elution technique was not effective for removing iron from the resin. Cyanide associated with base metals was recovered as NaCN. Some oxidation of cyanide was noticed, subject to the elution conditions.This oxidative acid elution process could be used in commercial operations for the selective elution of base metals from a strong base ion exchange resin bed operating in alternative adsorption/base metal elution cycles. Thus, virtually all metal cyanide species could be recovered from cyanide leached solutions or slurries to give relatively clean tailings without compromising precious metal recovery efficiency. The process also caters for cyanide recovery and recycling.     

内蒙古某铀矿两种树脂淋洗方式的试验研究

以某铀矿过滤筛管结构的固定床为对象,开展了顺流带压淋洗和静态浸泡淋洗试验研究,并从淋洗效率及经济效益等方面对2种淋洗方式进行对比。结果表明:采用静态浸泡淋洗方式比顺流带压淋洗方式饱和树脂淋洗合格液平均铀浓度提高5.97g/L,淋洗贫液体积减少0.65床层体积倍数,有效减少了淋洗曲线拖尾现象;此外,静态浸泡的淋洗方式每塔可节约淋洗剂0.85床层体积倍数,有效地降低了生产成本。研究证明了静态浸泡淋洗方式对过滤网结构固定床淋洗的可行性。     

Selective adsorption of precious metals from hydrochloric acid solutions using porous carbon prepared from barley straw and rice husk

Porous carbon was prepared by carbonization from agro-waste such as rice husk and barley straw to evaluate the adsorption of precious and base metals from metal solutions. The effects of hydrochloric acid concentration, metal ion concentration, and contact time on adsorption were examined. Rice husk carbon was found to be highly selective for Au(III) and inert to Pt(IV), Pd(II) and other base metals. Barley straw carbon adsorbed these three precious metal ions, but was inert to base metal ions such as Cu(II), Fe(III) and Ni(II). The maximum adsorption capacity of rice husk carbon for Au(III) was 0.76 mol/kg and the maximum adsorption capacity of barley straw carbon for Au(III), Pt(IV) and Pd(II) was 1.47, 0.39 and 0.64 mol/kg, respectively. The effectiveness of recovery of precious metals from industrial solution was also tested and barley straw carbon was found to be highly efficient and selective for the targeted metal ions in the presence of excess of other metal ions. Rice husk and barley straw carbon are thus potential alternatives to commercially available activated carbon as they have high selectivity and are efficient with low production costs.     

Recovery by hydrometallurgical extraction of the platinum-group metals from car catalytic converters

The car industry is one of the technological applications which more platinum-group metals (PGM) employs. Therefore, the recovery of the PGMs from the car catalytic converters could be an important source to obtain these precious metals, with economic and environmental consequences.In this work, the car catalytic converters were characterized through different techniques as X-ray diffraction, scanning electron microscopy and inductively coupled plasma.In order to suggest an environmentally friendly method for the recovery of PGMs, some conditions such as the reagents concentration and composition, energy optimization, pre-treatment in hydrogen atmosphere and a thermal pre-treatment were studied.In addition, a new alternative to recover at least the 95% of the PGMs present in the car catalytic converters by the application of lees aggressive, corrosive or expensive reagents and conditions is proposed.     

Treatment of acid mine water by use of heavy metal precipitation and ion exchange

Acid mine water from a South African gold mine was characterised and treated by the precipitation of heavy metals with lime and sulphides, followed by ion exchange. The novelty of the proposed process lies in the use of carrier magnetic materials for more effective separation of water and solids, as well as the oxidation pretreatment that is also used to sterilize the water. The process can generate very, pure water from acid mine water with a great flexibility and an acceptable cost. The oxidation and precipitation of heavy metals with lime and subsequent sulphide-carrier magnetic separation appeared to be particularly suitable for the removal of heavy metal ions from the effluent of the particular gold mine that was investigated. The cation exchange resin IR120 can be used to reduce the salinity of the effluent of mine water after removal of heavy metals by precipitation. Low cost sulphuric acid can be used as the cation resin regenerator. The anion exchange resin A375 could reduce the anions (sulphate, chloride, bromide and fluoride) to acceptably low levels in the mine water after precipitation of heavy metals. A combination of sodium hydroxide and saturated lime solution can be used as the anion resin regenerator. A mixture of acidic gypsum from the cation elution section and alkaline gypsum from the anion elution section could generate high quality gypsum as byproduct, which could be sold as a valuable raw material to the gypsum industry, to offset process cost. Although these experiments were conducted on the acid mine water of a specific mine, the process could be extended to other mine waters contaminated with heavy metals and high salinities.