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Conditions for Thermal Activation of Ngwo Clay as an Alternative Resource for Alumina 预览
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作者 Udochukwu Mark Charles Nwachukwu Anyakwo +1 位作者 Okechukwu Onyebuchi Onyemaobi Chijioke Samson Nwobodo 《自然资源(英文)》 2019年第1期1-15,共15页
The thermal activation of Ngwo clay from southeastern Nigeria for optimal leaching of alumina was investigated. The clay assayed 24.63% Al2O3 and 52.15% SiO2, comprising mainly kaolinite mineral and free silica or qua... The thermal activation of Ngwo clay from southeastern Nigeria for optimal leaching of alumina was investigated. The clay assayed 24.63% Al2O3 and 52.15% SiO2, comprising mainly kaolinite mineral and free silica or quartz. The alumina locked up in the clay structure was rendered acid-soluble by thermal activation which transformed the clay from its crystalline nature to an amorphous, porous phase or metakaolinite. The clay samples were heated at calcination temperatures of 500°C, 600°C, 700°C, 800°C, and 900°C at holding times of 30, 60, and 90 minutes. Uncalcined clay samples and samples calcined at 1000°C (holding for 60 minutes) were used in the control experiments. After leaching the resulting clay calcines in 1 M hydrochloric acid solution at room temperature, it was observed that the clay calcines produced at 700°C (holding for 60 minutes) responded most to leaching. Samples calcined for 60 minutes also responded better than those held for 30 or 90 minutes. Based on activation energy studies, it was observed that calcines produced at 700°C (for 60 minutes) had both the highest leaching response (51.84%?after 1 hour at leaching temperature of 100°C) and the lowest activation energy of 25.03 kJ/mol. It is concluded therefore that Ngwo kaolinite clay should?be best calcined for alumina dissolution by heating up to 700°C and holding for 60 minutes at that temperature. The clay deposit has potential for use as alternative resource for alumina production in Nigeria where bauxite is scarce. 展开更多
关键词 Ngwo CLAY BAUXITE KAOLINITE ALUMINA CALCINATION Thermal Activation LEACHING
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Determination of the Calcination Procedure Required to Activate Edda Clay for Optimal Leaching of Alumina 预览
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作者 Udochukwu Mark Charles Nwachukwu Anyakwo +1 位作者 Okechukwu Onyebuchi Onyemaobi Chijioke Samson Nwobodo 《矿物质和材料特性和工程(英文)》 2019年第2期49-63,共15页
Nigeria is the highest consumer of aluminium in Africa but lacks bauxite deposits. The replacement of bauxite alumina with other alumina bearing resources (clays in particular) has been proposed. The present study inv... Nigeria is the highest consumer of aluminium in Africa but lacks bauxite deposits. The replacement of bauxite alumina with other alumina bearing resources (clays in particular) has been proposed. The present study investigated the thermal treatment required to activate Edda clay from southeastern Nigeria for optimal leaching of alumina. The clay is composed mainly of kaolinite and quartz, assaying 24.65% Al2O3 and 52.81% SiO2. Thermal activation of the clay prior to leaching transformed the crystalline kaolinite mineral to an amorphous phase (metakaolinite) in which the alumina became soluble. Clay samples passing 300 μm sieve were calcined at temperatures of 500°C, 600°C, 700°C, 800°C, and 900°C at holding times of 30, 60, and 90 minutes in each case. The uncalcined clay and sample heated at 1000°C (for 60 minutes) were used in the control experiments. Leaching of alumina from the resulting clay calcines was done in 1 M hydrochloric acid solution at room temperature using a solid/liquid ratio of 0.02 g/ml and shaking speed of 100 rpm. The solubility data based on the percentage of Al ions taken into leach solution showed that the sample calcined at 700°C (for 60 minutes) responded to leaching better than other samples. Samples calcined for 60 minutes at all temperatures studied were found to respond more than those held for 30 or 90 minutes. Studies on the activation energy of leaching revealed that calcines produced at 700°C (for 60 minutes) had both the highest leaching response (49.96% after 1 hour at leaching temperature of 100°C) and the lowest activation energy of 24.47 kJ/mol. It is concluded therefore that Edda kaolinite clay should be thermally activated for alumina yield by heating up to 700°C and holding for 60 minutes. The clay deposit is therefore a potential alternative resource for alumina production. 展开更多
关键词 Edda CLAY Bauxite KAOLINITE ALUMINA CALCINATION Thermal Activation LEACHING
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Effect of Calcination Condition on Thermal Activation of Ibere Clay and Dissolution of Alumina 预览
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作者 Udochukwu Mark Charles Nwachukwu Anyakwo +1 位作者 Okechukwu Onyebuchi Onyemaobi Chijioke Samson Nwobodo 《有色冶金(英文)》 2019年第2期9-24,共16页
Bauxite deposits for production of alumina are lacking in Nigeria and there is an aluminium smelter plant in the country which requires alumina for its operation. Development of alternative alumina resource using clay... Bauxite deposits for production of alumina are lacking in Nigeria and there is an aluminium smelter plant in the country which requires alumina for its operation. Development of alternative alumina resource using clays that are abundant in the country is the focus of this paper. The thermal activation of Ibere clay from southeastern Nigeria for optimal leaching of alumina was investigated. The clay assayed 28.52% Al2O3 and 51.6% SiO2, comprising mainly kaolinite mineral and quartz or free silica. The alumina locked up in the clay structure was rendered acid-soluble by thermal activation which transformed the clay from its crystalline nature to an amorphous, anhydrous phase or metakaolinite. The clay samples were heated at calcination temperatures of 500°C, 600°C, 700°C, 800°C, and 900°C at holding times of 30, 60, and 90 minutes. Uncalcined clay samples and samples calcined at 1000°C (holding for 60 minutes) were used in the control experiments. The result of leaching the clay calcines in 1 M hydrochloric acid solution at room temperature, showed that the clay calcines produced at 600°C (holding for 60 minutes) responded most to leaching. Samples calcined for 60 minutes also responded better than those held for 30 or 90 minutes. Based on activation energy studies, it was observed that calcines produced at 600°C (for 60 minutes) had both the highest leaching response (50.27% after 1 hour at leaching temperature of 100°C) and the lowest activation energy of 24.26 kJ/mol. It is concluded therefore that Ibere kaolinite clay should be best calcined for alumina dissolution by heating up to 600°C and holding for 60 minutes at that temperature. The clay deposit has potential for use as alternative resource for alumina production in Nigeria where bauxite is scarce. 展开更多
关键词 Ibere CLAY BAUXITE KAOLINITE ALUMINA CALCINATION Thermal Activation Leaching
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中国铝土矿的供应安全评价 预览
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作者 任晓娟 范凤岩 +1 位作者 柳群义 樊礼军 《中国矿业》 北大核心 2019年第7期52-59,共8页
中国作为氧化铝、原铝生产消费大国,铝土矿资源贫乏、长期供应不足,供应安全形势严峻。因此针对我国铝土矿供应安全状况评价以及未来供应趋势的判断非常必要。本文利用2000~2018年的数据从资源禀赋安全、国内供需安全、进口市场安全三... 中国作为氧化铝、原铝生产消费大国,铝土矿资源贫乏、长期供应不足,供应安全形势严峻。因此针对我国铝土矿供应安全状况评价以及未来供应趋势的判断非常必要。本文利用2000~2018年的数据从资源禀赋安全、国内供需安全、进口市场安全三个方面出发,建立中国铝土矿供应安全评价指标体系,利用熵权-TOPSIS法对2000~2018年铝土矿的安全趋势进行评价,并基于评价结果运用分数阶算子灰色模型对未来的安全趋势进行预测。结果表明:2000~2002年我国铝土矿供应较安全,2003~2005年我国铝土矿供应基本安全,2006~2018年我国铝土矿供应较危险,2019~2023年我国铝土矿供应仍然较危险。 展开更多
关键词 铝土矿 供应安全 熵权-TOPSIS法 分数阶算子灰色模型
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中国铝土矿进口来源国国别研究 预览 被引量:1
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作者 潘昭帅 张照志 +2 位作者 张泽南 封国权 曹晓森 《中国矿业》 北大核心 2019年第2期13-17,24共6页
近五年来,中国铝土矿的年均进口量约5500万t,对外依存度为45%,而未来年均仍需进口约7000万t的优质铝土矿石,对外依存度将长期维持在40%~50%。因此,如何获取稳定的境外铝土矿资源成为目前急需解决的问题。本文介绍了澳大利亚等六个铝土... 近五年来,中国铝土矿的年均进口量约5500万t,对外依存度为45%,而未来年均仍需进口约7000万t的优质铝土矿石,对外依存度将长期维持在40%~50%。因此,如何获取稳定的境外铝土矿资源成为目前急需解决的问题。本文介绍了澳大利亚等六个铝土矿主要来源国的资源、产量等情况,利用改进的多样性指数和投资组合模型,选取资源、产量、对华贸易、地缘政治和运输五个指标,综合分析各个主要来源国的进口安全状况,得出我国未来获取铝土矿的优选次序依次为几内亚、澳大利亚、巴西、印度尼西亚、印度、马来西亚。另外,提出了未来中国要合理规划铝土矿布局和实现产能转移等建议。 展开更多
关键词 铝土矿 进口来源国 对华贸易 国别分析 优选标准
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南川大佛岩铝土矿区钛、硫含量与铝土矿成矿的关系 预览
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作者 赵婕 唐将 +1 位作者 陈林华 傅林 《贵州地质》 2019年第3期246-249,共4页
通过南川大佛岩铝土矿矿床特征的分析及对铝土矿体中Al 2O 3与Ti、S含量关系的研究发现,铝土矿体中TiO 2与Al 2O 3含量成正相关关系。在含矿岩系中若无连续成片的TiO 2含量大于2.0%的地段,说明原生沉积阶段红土化程度低,初始铝土矿形成... 通过南川大佛岩铝土矿矿床特征的分析及对铝土矿体中Al 2O 3与Ti、S含量关系的研究发现,铝土矿体中TiO 2与Al 2O 3含量成正相关关系。在含矿岩系中若无连续成片的TiO 2含量大于2.0%的地段,说明原生沉积阶段红土化程度低,初始铝土矿形成条件差,难以形成铝土矿工业矿体,TiO 2含量可作为初始铝土矿含矿岩系质量(红土化程度)优劣的指示元素。铝土矿中硫含量的高低,受后期改造影响明显,可以将S作为铝土矿区后生改造程度强弱的指示元素。 展开更多
关键词 铝土矿 成矿特征 重庆南川
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广西那坡县龙合矿区稀土矿与铝土矿伴生情况 预览
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作者 营新 《世界有色金属》 2019年第10期101-102,共2页
稀土矿、铝土矿是我国矿产资源中重要的两种,用途极为广泛,不管是军事装备、化学冶金等其他方面,都离不开。本文主要研究地质特殊现象广西某些矿区内存在着稀土矿与铝土矿的伴生情况,希望通过研究,能对今后的稀土矿、铝土矿资源开采和... 稀土矿、铝土矿是我国矿产资源中重要的两种,用途极为广泛,不管是军事装备、化学冶金等其他方面,都离不开。本文主要研究地质特殊现象广西某些矿区内存在着稀土矿与铝土矿的伴生情况,希望通过研究,能对今后的稀土矿、铝土矿资源开采和利用提供一定的参考和借鉴。 展开更多
关键词 稀土矿 铝土矿 伴生
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矿产综合机械化开采工艺在铝土矿的应用 预览
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作者 周其安 《世界有色金属》 2019年第7期293-293,296共2页
本文首先对煤矿综合机械化开采工艺中使用的设备进行了简要介绍,论述该工艺的特点及在实际应用于铝土矿开采时存在的问题,分析综合机械化开采工艺在铝土矿开采中应用的可行性,供相关工作人员参考借鉴。
关键词 铝土矿 开采工艺 煤矿综和机械化
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广西某高硫高铁铝土矿拜耳法溶出试验研究 预览
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作者 陈燕清 《矿产综合利用》 CAS 北大核心 2019年第2期46-50,15共6页
针对广西某地高硫高铁一水硬铝石型铝土矿的矿石特性,采用浮选脱硫-拜耳法溶出工艺流程,对其进行反浮选除硫再进行拜耳法溶出试验。结果表明,该高硫高铁铝土矿可通过浮选方法脱硫,脱硫尾矿进行拜耳法溶出可以得到较佳的溶出效果。其较... 针对广西某地高硫高铁一水硬铝石型铝土矿的矿石特性,采用浮选脱硫-拜耳法溶出工艺流程,对其进行反浮选除硫再进行拜耳法溶出试验。结果表明,该高硫高铁铝土矿可通过浮选方法脱硫,脱硫尾矿进行拜耳法溶出可以得到较佳的溶出效果。其较佳的溶出条件为溶出温度260℃、溶出时间45 min、配料分子比1.4、石灰加入量10%、循环母液苛性碱浓度260 g/L,在此条件下氧化铝的相对溶出率达到99.40%。 展开更多
关键词 铝土矿 浮选 拜耳法 溶出率
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铝土矿中铝、铁和硅有价组分的综合利用研究 预览
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作者 刘佳囡 曹诗圆 +2 位作者 程颖 黄建帝 常龙娇 《矿产综合利用》 CAS 北大核心 2019年第4期87-90,共4页
针对山东某地铝土矿高铝、高铁、高硅、低铝硅比的特点,设计了一个综合利用矿石中铝、铁、硅的工艺流程。通过硫酸铵焙烧、水浸、过滤,矿石中的铝、铁等有价组元进入浸出液中,二氧化硅在渣中富集。利用不同金属离子的溶度积的差别,通过... 针对山东某地铝土矿高铝、高铁、高硅、低铝硅比的特点,设计了一个综合利用矿石中铝、铁、硅的工艺流程。通过硫酸铵焙烧、水浸、过滤,矿石中的铝、铁等有价组元进入浸出液中,二氧化硅在渣中富集。利用不同金属离子的溶度积的差别,通过加入沉淀剂碳酸铵调节溶液pH值,滤液中的铁和铝分别以氢氧化铁和氢氧化铝的形式析出,再经高温煅烧得氧化铁和氧化铝粉体。氧化铁的回收率可达85%以上,氧化铝的回收率可达95%以上。硫酸铵低温焙烧铝土矿的工艺实现了铝、铁和硅的综合利用,整个流程无废物、废水和废气的排放。 展开更多
关键词 铝土矿 综合利用 硫酸铵 氧化铝 微硅粉 氧化铁
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高铝矾土改性对稻草热解与气化特性的影响
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作者 王金德 裴海鹏 +2 位作者 金保昇 戴昕 孙漪清 《过程工程学报》 CAS CSCD 北大核心 2019年第4期783-791,共9页
在固定床中研究了高铝矾土改性剂及其浓度和反应温度对稻草热解产气特性的影响,选取固定床中最佳实验条件,在流化床中研究了改性高铝矾土床料对稻草气化特性及焦油产率的影响。结果表明,不同物质改性的高铝矾土对稻草热解产气特性的影... 在固定床中研究了高铝矾土改性剂及其浓度和反应温度对稻草热解产气特性的影响,选取固定床中最佳实验条件,在流化床中研究了改性高铝矾土床料对稻草气化特性及焦油产率的影响。结果表明,不同物质改性的高铝矾土对稻草热解产气特性的影响不同,4种物质提高稻草热解产气能力的顺序为CaCl2<Fe(NO3)3<CuCl2≈Ni(NO3)2。增加CuCl2改性剂浓度,其在高铝矾土上的有效负载量成倍增加,稻草热解产气量也增加,热解气低位热值由2.93 MJ/Nm3提高至3.89 MJ/Nm^3;反应温度提高对改善稻草热解产气组分有促进作用,800℃下CO,H2和CH4产量分别比650℃下增加40.6%,110.8%和70.0%,热解气低位热值从1.74 MJ/Nm^3升至4.09 MJ/Nm3。改性高铝矾土提高了稻草气化产气量,减少了焦油含量,焦油含量从27.01g/m^3降至20.09 g/m^3,气化产气低位热值由3.74 MJ/Nm3升至4.28 MJ/Nm3,气化率由28.25%提升至34.51%。 展开更多
关键词 生物质 催化 高铝矾土 稻草 热解气 焦油
Electrochemical behaviors of anode materials and their performance for bauxite desulfurization
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作者 Yingnan Hu Aijing Lü +4 位作者 Mingyong Wang Dong Wang Junhao Liu Zhi Wang Xuzhong Gong 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第4期802-810,共9页
Pyrite inside bauxite could be oxidized into soluble S-containing ions by electrolysis, and thus achieving bauxite desulfurization by using filtration. However, S-containing ions in electrolyte had some corrosion effe... Pyrite inside bauxite could be oxidized into soluble S-containing ions by electrolysis, and thus achieving bauxite desulfurization by using filtration. However, S-containing ions in electrolyte had some corrosion effects on electrode, especially for anode. In this work, six kinds of traditional materials were selected as anode, and their corrosion behaviors were examined by using electrochemistry characterization. Tafel and CV curves from simulating electrolyte suggested that their corrosion potentials were in the following order: Ni﹥C﹥SS﹥Fe﹥Cu﹥Pb–Ag. As expected, the desulfurization ratio and cell voltage from bauxite electrolysis were in the following order respectively: Cu﹥Ni﹥Fe﹥SS﹥C﹥Pb–Ag and Ni﹥Fe﹥SS﹥Cu﹥C﹥Pb–Ag. Finally, Ni was proposed a kind of excellent electrode material for bauxite desulfurization from electrolysis. 展开更多
关键词 Corrosion resistance High SULFUR BAUXITE ELECTROLYSIS DESULFURIZATION ELECTRODE materials
广西平果太平矿区外围铝土矿石工艺矿物学研究 预览
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作者 夏瑜 罗星 +3 位作者 周卫宁 马荣锴 吴杰 刘奕志 《岩石矿物学杂志》 CAS CSCD 北大核心 2019年第4期579-586,共8页
以广西平果县太平铝土矿区外围的矿石为研究对象,采用化学分析、X射线粉晶衍射、光学显微鉴定、X射线能谱分析等方法对矿石的化学组成、矿物组成、矿物嵌布特征等进行了系统研究。结果表明,太平矿区外围铝土矿属于高铁的一水硬铝石型铝... 以广西平果县太平铝土矿区外围的矿石为研究对象,采用化学分析、X射线粉晶衍射、光学显微鉴定、X射线能谱分析等方法对矿石的化学组成、矿物组成、矿物嵌布特征等进行了系统研究。结果表明,太平矿区外围铝土矿属于高铁的一水硬铝石型铝土矿,其中Al2O3含量为53. 06%,A/S值为10. 74,适用于拜耳法回收;共伴生组分中Fe2O3、TiO2、Ga、Nb达到综合回收利用指标。矿石选冶回收的目标元素Al主要以一水硬铝石、三水铝石的形式存在,平衡配分占比分别为85. 9%、6. 73%。矿石复杂的结构构造、矿物嵌布粒度、矿石中Fe、Si等元素不均匀分布等因素对Al的选冶回收有一定的影响。 展开更多
关键词 平果县太平矿区 铝土矿 工艺矿物学 一水硬铝石
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铝土矿酸性浸出液中铝、铁的回收 预览
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作者 刘佳囡 黄建帝 +2 位作者 曹诗圆 常龙娇 刘连利 《矿冶》 CAS 2019年第4期84-88,共5页
以铝土矿酸性浸出液为原料,通过化学沉淀、碱溶、碳分、煅烧等得到氧化铁和氧化铝粉体。考察了沉淀、碱溶、碳分过程中溶液终点pH值、反应温度、反应时间等参数的影响,得到优化工艺条件。结果表明,在终点pH值5.0、反应温度80℃、沉淀时... 以铝土矿酸性浸出液为原料,通过化学沉淀、碱溶、碳分、煅烧等得到氧化铁和氧化铝粉体。考察了沉淀、碱溶、碳分过程中溶液终点pH值、反应温度、反应时间等参数的影响,得到优化工艺条件。结果表明,在终点pH值5.0、反应温度80℃、沉淀时间50min条件下进行沉淀,铝铁的沉淀率均达99%;在溶液终点pH值14、碱溶温度80℃、碱溶时间30min条件下,铝的溶出率可达99.42%,铁的去除率可达99.63%;在溶液终点pH值9.0、碳分温度40℃、CO2流速选择6mL/min条件下,铝的沉淀率可达98.69%。 展开更多
关键词 铝土矿 浸出液 氧化铝 氧化铁
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道真桃园铝土矿矿床地质特征及找矿标志 预览
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作者 冯忠生 《世界有色金属》 2019年第10期70-71,共2页
黔北道真桃园铝土矿产于二叠系中统梁山组(P2l)的碎屑岩中,其成矿时代为寒武纪-中志留世时期,根据矿床沉积机制,铝土矿成因类型属侵蚀间断面上,滨海沉积型铝土矿床,在总体结构构造、地层、岩石、矿物、地貌找矿标志的基础上,建立找矿模... 黔北道真桃园铝土矿产于二叠系中统梁山组(P2l)的碎屑岩中,其成矿时代为寒武纪-中志留世时期,根据矿床沉积机制,铝土矿成因类型属侵蚀间断面上,滨海沉积型铝土矿床,在总体结构构造、地层、岩石、矿物、地貌找矿标志的基础上,建立找矿模式,认为道真地区地表工作程度较高,今后的主要任务是根据区域性的找矿标志及找矿模式,并遵循“从已知到未知”的原则,预测和重视深部找矿。此为扩大区域铝土矿远景规模的重要途径。 展开更多
关键词 铝土矿 找矿标志 地质特征 道真桃园
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China Calcined Bauxite Market Production and Outlook 预览
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作者 David WANG Haoran YU Lingyan 《中国耐火材料:英文版》 CAS 2019年第1期28-31,共4页
The resources, mining capacity and calcination capacity of refractory grade bauxite in China market were introduced.Then major environmental protection regulations launched over the past years were briefly reviewed. M... The resources, mining capacity and calcination capacity of refractory grade bauxite in China market were introduced.Then major environmental protection regulations launched over the past years were briefly reviewed. Meanwhile some thoughts about the outlook of the market were shared. 展开更多
关键词 CALCINED BAUXITE OUTLOOK ENVIRONMENTAL protection REGULATIONS
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综合机械化开采方法在铝土矿的应用研究 预览
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作者 孔超 彭文 《世界有色金属》 2019年第11期37-39,共3页
根据贵州瓦厂坪铝土矿开采技术条件,介绍了走向长壁式综合机械化开采方法在贵州瓦厂坪铝土矿开采过程中的应用,叙述了设备选型方法。
关键词 铝土矿 综合机械化开采 设备选型
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贵州道真县河照岩铝土矿床地质特征及找矿标志 预览
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作者 朱尤青 《现代矿业》 CAS 2019年第7期69-72,共4页
通过对黔北道真地区河照岩铝土矿床的地质特征研究表明,区内含矿体系整体为一套黏土岩-铝土矿-铝质岩组合,铝土矿体主要产于中二叠统梁山组地层中,矿体产状与围岩基本一致,呈似层状及透镜状产出。在结合前人研究成果的基础上,探讨了矿... 通过对黔北道真地区河照岩铝土矿床的地质特征研究表明,区内含矿体系整体为一套黏土岩-铝土矿-铝质岩组合,铝土矿体主要产于中二叠统梁山组地层中,矿体产状与围岩基本一致,呈似层状及透镜状产出。在结合前人研究成果的基础上,探讨了矿床成因,同时对该区的找矿标志进行了总结,以期为该区后期的找矿勘探工作提供某些启示。 展开更多
关键词 铝土矿 地质特征 找矿标志
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古风化壳型铝土矿中稀土元素地球化学特征 预览
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作者 宋立方 杜登峰 +1 位作者 李献龙 王利兵 《矿产勘查》 2019年第5期1141-1146,共6页
为了研究古风化壳型铝土矿中稀土元素的含量及地球化学特征,探讨稀土元素对古风化壳型铝土矿的成因及成矿环境的指示意义。本文以山西沁源县高家山铝土矿、贵州修文小山坝铝土矿、广西靖西县念寅铝土矿、河南申家沟铝土矿为例,并结合前... 为了研究古风化壳型铝土矿中稀土元素的含量及地球化学特征,探讨稀土元素对古风化壳型铝土矿的成因及成矿环境的指示意义。本文以山西沁源县高家山铝土矿、贵州修文小山坝铝土矿、广西靖西县念寅铝土矿、河南申家沟铝土矿为例,并结合前人的研究成果,认为铝土矿的成矿物质来源可能来自底板碳酸盐岩。根据《矿产资源工业要求手册》风化壳型稀土矿边界品位REO>0.07%,上述四个矿床铝土矿中稀土含量大多达到或超过标准,具有巨大的潜在经济价值。 展开更多
关键词 铝土矿 稀土 古风化壳 地球化学
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Extraction of iron and aluminum from high-iron bauxite by ammonium sulfate roasting and water leaching
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作者 Ding Tian Xiao-yi Shen +2 位作者 Yu-chun Zhai Penny Xiao Paul Webley 《钢铁研究学报:英文版》 SCIE EI CAS CSCD 2019年第6期578-584,共7页
High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternat... High iron content is one of the challenges in utilizing the refractory bauxites in China. An improved method for treating the high-iron bauxite by roasting with (NH4)2SO4 was proposed, which offers a possible alternative method for utilizing the high-iron bauxite. The influences of the roasting time, roasting temperature, material ratio, and ore particle size on the extraction ratios of Fe and Al were studied, and the orthogonal test was used to optimize the reaction conditions. The optimized reaction conditions were proposed as follows: roasting temperature of 450 °C, roasting time of 120 min, material ratio of (NH4)2SO4 to ore of 2.5:1.0, and ore particle size below 80 jim. The roasting mechanism and kinetic parameters including the apparent activation energy and reaction rate constant were investigated. The results showed that the control step of the roasting process was the internal diffusion on the product layer and the apparent activation energy was 19.22 kJ mol-1 in the reaction temperature range. The kinetic equation was obtained finally. 展开更多
关键词 High-iron BAUXITE AMMONIUM SULFATE ROASTING Reaction process Kinetics
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