共查询到19条相似文献,搜索用时 390 毫秒
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本方法属于用湿法冶金的方法处理包括氰渣在内的难选的含金硫化矿精矿、以提取贵金属的范畴,即用碱性分解含黄铁矿和砷黄铁矿的处理方法。尽管已经掌握了在高压釜内用强碱分解含金硫化精矿的方法和用电化学氧化分解的方法,但这些方法需要昂贵的设备,为了维持生产还需要高额流动资金购买化学药品。其它的处理方法是超细磨矿,与添加的氧化剂(NH_4NO_3)一起在200~300℃下焙烧,并在焙烧后浸入加有过氧化氢的碱性 相似文献
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开发绿色高效的钛铁矿精矿脱药方法,对其清洁利用具有重要意义。本文针对钛铁矿精矿,采用氧化脱药工艺,研究氧化剂种类、用量及脱药段数对精矿脱药率的影响;并采用扫描电镜(SEM)及红外光谱测试手段分析了氧化脱药的机理。研究结果表明,过氧化氢是钛铁矿精矿有效的脱药试剂,其可氧化解析吸附于钛铁矿表面的油酸钠。采用两段氧化脱药工艺,当第一段和第二段过氧化氢用量均为1100 g/t~1200g/t时,钛铁矿浮选精矿的总脱药率为71.97%。本研究可为浮选精矿的脱药提供一定的借鉴。 相似文献
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过氧化氢的氧化特性及其在不同介质中的分解行为研究 总被引:3,自引:0,他引:3
过氧化氢(H2O2)作为一种氧化剂曾广泛应用于湿法冶金工艺。本文针对过氧化氢在地下水、自来水、5g/LH2SO4和2g/LNH4HCO3四种不同介质中的分解情况进行了试验研究。研究结果表明:过氧化氢在碱性介质中很不稳定,而且质量浓度越高,分解速度越快;在酸性介质中比较稳定,分解速度慢,适合于酸性介质中作氧化剂,在碱性环境尽量少用或不用。此研究为更好地了解过氧化氢的化学特性及其在湿法冶金工艺中的应用,提供参考与借鉴。 相似文献
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用过氧化氢和过氧化钙处理金矿石的助浸工艺 总被引:1,自引:0,他引:1
金的助浸工艺已用于采金业,并达到了提高金回收率、加快浸出速率和降低氰化物消耗的目的。过氧化氢和过氧化钙均为过氧化剂,具体选择哪一种取决于选厂的生产工艺和矿石性质。本文通过分析实验室试验和工业试验,论述了过氧化剂在提金中的作用。 相似文献
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美国用适当的氧化剂由溶于含氨溶液的各种物料如难处理矿石和珠宝废料有效地提取金。本文报道了单体和各种矿物中的金溶于含氨溶液的电化学和动力学。研究了若干氧化剂包括氧 ,铜氨络物 ,钴氨络物和磺的作用。同时 ,讨论了游离氨 ,铵离子和其它盐的浓度对溶金总速率的影响。在约 160℃至190℃下 ,一步操作 1~ 2小时浸出后 ,可从硫化矿石和含碳矿石中回收 95%以上金和银。金的溶解受到反应温度和氨与氧化剂的浓度的极大影响。影响金在含氨溶液中溶解速度的因素@许孙曲 相似文献
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由华东理工大学卢冠忠教授任首席科学家的“高丰度稀土元素在环境保护领域中高效、高质利用的基础研究”项目在科技部立项并获2500万元资金支持。该项目针对清洁油品生产及清洁能源开发、化石燃料高效和超低污染应用以及废气净化处理等领域,开展稀土催化材料制备及应用基础研究。 相似文献
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The leaching of gold using alkaline amino acids–hydrogen peroxide solutions at low concentrations has been studied. The application of alkaline amino acid–hydrogen peroxide system may offer an alternative and environmentally benign process for gold leaching, particularly in the context of leaching low grade gold ores in an in-situ or in heap leach processes. In the presence of an oxidant or oxidants, it was found that amino acids can dissolve gold at alkaline condition at low and moderate temperature. Heating the leach solution between 40 and 60 °C was found to enhance the gold dissolution significantly in alkaline amino acid–peroxide solutions. It was also found that gold dissolution increases by increasing amino acid concentration, peroxide and pH. Amino acids acts synergistically to dissolve gold. Although glycine showed the highest gold dissolution as a single amino acid compared to histidine and alanine, histidine was found to enhance gold dissolution when used in equimolar amounts with glycine. The presence of Cu2+ ion enhances gold dissolution in the glycine–peroxide solutions. The process will propose an environmentally benign process for gold treatment in order to replace the use of cyanide in heap or in-situ leaching. In the presence of pyrite, the amount of gold leached was lower due to the peroxide consumption in sulphide oxidation. 相似文献
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《Minerals Engineering》2007,20(7):670-674
The dissolution of copper from chalcopyrite was investigated in the presence of hydrogen peroxide and ethylene glycol. Hydrogen peroxide was used as oxidant in the leaching process. Addition of a small amount of ethylene glycol significantly improved the copper dissolution. The copper leaching mechanism was established by examining the influence of various parameters on the reaction rate in the presence of ethylene glycol. The effect of temperature on the reaction kinetics suggests that the leaching reaction follows the surface reaction-controlled model. The linear relationship between the log of reaction rate constant and log of particle radius supports the proposed reaction model. The reaction order was calculated with respect to hydrogen peroxide which indicates that hydrogen peroxide has greater influence on the leaching kinetics. Stirring speed and sulfuric acid concentration are not important variables. Most of the sulfide ions were transformed to elemental sulfur during the reaction. The elemental sulfur was present on the surface of chalcopyrite residue as discrete crystalline particles instead of a coating of continuous film which causes the passivation of chalcopyrite surface. Ethylene glycol was found to stabilize the hydrogen peroxide at elevated temperature which could be another reason for enhanced recovery. 相似文献
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传统湿法冶金技术回收三元锂电池正极材料通常采用强酸为浸出剂,过氧化氢为还原剂。而强酸和过氧化氢均有强腐蚀性、二次气体污染及明显的细胞毒性。因此本论文采用葡萄糖还原磷酸浸出三元锂电池正极材料,研究了葡萄糖还原磷酸浸出过程中酸浓度、葡萄糖浓度、固液比、温度和时间对Li、Ni、Co和Mn浸出率的影响,在最佳条件下Li、Ni、Co和Mn的浸出率在95%以上。利用未反应收缩核模型拟合了酸浸过程的动力学数据,结果显示浸出过程由表面化学反应所控制。使用共沉淀-固相法再生了正极材料,其结晶性良好,元素分布均匀,实现了三元锂电池正极材料的闭环再生。 相似文献
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针对臭氧氧化工艺处理选矿废水在高污染污负荷条件下氧化性能不足及曝气设备易于结垢堵塞的问题,采用射流曝气耦合臭氧/过氧化氢协同氧化工艺处理选矿废水,考察了澄清预处理、水力停留时间、臭氧和过氧化氢投加量等工艺条件对处理效果的影响,并分析了不同污染物负荷条件下耦合工艺药剂投加量及直接运行成本。结果表明,射流曝气耦合臭氧/过氧化氢协同氧化工艺处理选矿废水效果良好,抗冲击能力强,原水需经沉淀预处理再氧化,可根据原水水质变化灵活调整氧化药剂的投加量,将废水处理至不影响回用程度的工艺条件为:臭氧投加量110~240 g/m3、过氧化氢投加量为2~4 L/ m3,水力停留时间约30 min。不同污染物负荷条件下处理成本为3.0-8.8元/吨水,该工艺是一个有前景的选矿废水处理研究和工程应用方向。 相似文献
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《Minerals Engineering》1999,12(2):165-174
The kinetics of pyrite oxidation by hydrogen peroxide in hydrochloric acid solutions were investigated. The effects of stirring, temperature, particle size as well as hydrogen peroxide and hydrochloric acid concentrations were studied. The effects of H+ and Cl− additions were also examined. The oxidation kinetics were found to follow a shrinking core model, with the surface chemical reaction as the rate-controlling step. This is in accord with an activation energy of 65 kJ/mol and a linear relationship between the rate constant and the reciprocal of the particle radius. The reaction order with respect to hydrogen peroxide concentration was found to be 1.32. The rate of pyrite oxidation was found to decrease as the hydrochloric acid concentration increases, most likely owing to the adsorption of chloride ions onto the surface of the pyrite particles. H+ ions had no effect on the rate, whereas Cl− ions had an effect similar to that of the hydrochloric acid. 相似文献
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以亚临界醋酸作为溶胀介质,辅以其他种类有机溶剂协同降解回收废旧碳纤维/环氧树脂复合材料。甲酸、丙酮、异丙醇可显著增强亚临界醋酸对环氧树脂的降解效果。研究了亚临界醋酸/甲酸混合介质对环氧树脂的协同降解特性,分析了处理温度、保温时间、甲酸添加量和固液比对环氧树脂降解率的影响。采用GC-MS、SEM-EDX以及单丝拉伸测试等测试手段分析了环氧树脂在亚临界醋酸/甲酸环境下的有机降解产物和回收碳纤维微观形貌特征与力学性能。最佳处理条件为260℃、40 mL乙酸、10 mL甲酸、保温60 min、固液比1∶50、压强7 MPa时,环氧树脂的降解率达到97.04%,回收碳纤维材料表面洁净,分散性好,回收碳纤维抗拉强度保持率为80%。 相似文献
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黄陵一号选煤厂煤泥重介旋流器粗煤泥分选系统精煤灰分偏高。试验研究发现,精煤和尾煤中存在中间密度级物料较多现象,使得尾煤灰分较低,而精煤灰分则较高。通过探索试验和评价试验得出,运用干扰床分选机分选粗煤泥,可得到符合要求的精煤和尾煤。入料、精煤和尾煤的小筛分和小浮沉试验表明,干扰床分选机分选的数量效率为98.59%,可能偏差为0.11,错配物总量为5.7%,对粗煤泥具有良好的分选效果。 相似文献