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铁矿石中酸溶亚铁含量测量不确定度评定
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作者 宋飞 马李 +2 位作者 陈哲 丁仕兵 管嵩 《现代矿业》 CAS 2023年第1期187-190,194,共5页
为评定铁矿石中酸溶亚铁含量重铬酸钾氧化还原滴定测量的不确定度,对样品前处理及重铬酸钾与酸溶亚铁的化学反应过程、滴定等步骤建立数学评定模型。通过科克伦检验,得出日常的酸溶亚铁检测精度没有显著性差异,回归分析表明,标准偏差和... 为评定铁矿石中酸溶亚铁含量重铬酸钾氧化还原滴定测量的不确定度,对样品前处理及重铬酸钾与酸溶亚铁的化学反应过程、滴定等步骤建立数学评定模型。通过科克伦检验,得出日常的酸溶亚铁检测精度没有显著性差异,回归分析表明,标准偏差和酸溶亚铁含量之间没有显著性的相关关系,以合并样本标准偏差作为A类不确定度。B类不确定度的来源主要涉及天平、滴定管、容量瓶等误差,对其逐一量化并通过数学模型进行合成,从而计算合成不确定度和扩展不确定度。最终得到氧化亚铁测量值在0.2%~20%,单次检测的A类不确定度为0.06%。在评定过程发现,滴定体积是不确定度的最大来源,实验改进措施是适当扩大滴定体积和使用更高精度的滴定管。 展开更多
关键词 铁矿石 酸溶亚铁 不确定度 包含概率
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固体废物——氧化皮中酸溶亚铁的特征及其含量测定
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作者 刘美东 丁仕兵 +1 位作者 孙博 于立洋 《检验检疫学刊》 2011年第2期14-15,71,共3页
氧化皮中FeO、Fe3O4物相较多,完全氧化态Fe2O3含量比较少。本文采用在二氧化碳气体保护下,用盐酸分解试样,以二苯胺磺酸钠为指示剂,用重铬酸钾标准溶液滴定测试FeⅡ含量。用此方法对2个样品分别进行了7次测量,标准偏差为0.060%、0.075%... 氧化皮中FeO、Fe3O4物相较多,完全氧化态Fe2O3含量比较少。本文采用在二氧化碳气体保护下,用盐酸分解试样,以二苯胺磺酸钠为指示剂,用重铬酸钾标准溶液滴定测试FeⅡ含量。用此方法对2个样品分别进行了7次测量,标准偏差为0.060%、0.075%,相对标准偏差为0.17%、0.12%,回收率在100.12%-100.39%之间。将FeⅡ、TFe/FeⅡ与进口铁矿比较,发现FeⅡ含量可以作为初步鉴别氧化皮的特征。 展开更多
关键词 氧化皮 酸溶亚铁 鉴别
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Reaction behavior of kaolinite with ferric oxide during reduction roasting 被引量:20
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作者 Xiao-bin LI Hong-yang WANG +4 位作者 Qiu-sheng ZHOU Tian-gui QI Gui-hua LIU Zhi-hong PENG Yi-lin WANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期186-193,共8页
The pre-separation of silica and alumina in aluminosilicates is of great significance for efficiently treating alumina-/ silica-bearing minerals for alumina production. In this work, the reaction behavior of kaolinite... The pre-separation of silica and alumina in aluminosilicates is of great significance for efficiently treating alumina-/ silica-bearing minerals for alumina production. In this work, the reaction behavior of kaolinite with ferric oxide during reduction roasting was investigated. The results of thermodynamic analyses and reduction roasting experiments show that ferrous oxide obtained from ferric oxide reduction preferentially reacts with alumina in kaolinite to form hercynite, meanwhile the silica in kaolinite is transformed into quartz solid solution and/or cristobalite solid solution. With increasing roasting temperature, fayalite formed by reaction of surplus ferrous oxide with silica at low temperature is reduced to silica and metallic iron in the presence of sufficient carbon dosage. However, increasing roasting temperature and decreasing Fe2O3/Al2O3 molar ratio favor mullite formation. The complete conversion of kaolinte into free silica and hercynite can be obtained by roasting raw meal of kaolin, ferric oxide and coal powder with Fe2O3/Al2O3/C molar ratio of 1.2:2.0:1.2 at 1373 K for 60 min. This work may facilitate the development of a technique for comprehensively utilizing silica and alumina in aluminosilicates. 展开更多
关键词 KAOLIN FE2O3 HERCYNITE quartz solid solution cristobalite solid solution reduction roasting
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Bioleaching of pyrrhotite by Sulfobacillus thermosulfidooxidans 被引量:1
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作者 倪章元 顾帼华 +1 位作者 杨慧沙 邱冠周 《Journal of Central South University》 SCIE EI CAS 2014年第7期2638-2644,共7页
The bioleaching of pyrrhotite was investigated using Sulfobacillus thermosulfidooxidans.The effects of pH,pulp concentration,inoculation amount,external addition of ferrous and ferric ions were examined.The pH is foun... The bioleaching of pyrrhotite was investigated using Sulfobacillus thermosulfidooxidans.The effects of pH,pulp concentration,inoculation amount,external addition of ferrous and ferric ions were examined.The pH is found to exert a profound effect on the leaching process for controlling the bacterial activity and precipitation of ferric ions mainly as jarosite.The results show that low pulp content increases the leaching rate of iron.The inoculation amount from 1×107 cell/mL to 1×108 cell/mL has positive effects on the leaching rate.The results also imply that addition of ferrous sulfate(1 g/L) is required for the bacteria to efficiently drive the extraction of iron,however,the leaching efficiency has no obvious enhancement when 2 g/L ferrous sulfate was added.Comparatively,addition of ferric sulfate(2 g/L) significantly inhibits the bioleaching process.At the end of bioleaching,jarosite and sulfur are observed on the surface of pyrrhotite residues by using XRD and SEM.With the passivation film formed by jarosite and sulfur,the continuous iron extraction is effectively blocked. 展开更多
关键词 PYRRHOTITE BIOLEACHING Sulfobacillus thermosulfidooxidans JAROSITE
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Effect of iron valence on hydrothermal preparation of pyrochlore-type tungsten oxide
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作者 Qiu-sheng ZHOU Min XIANG +4 位作者 Dong LI Xiao-bin LI Tian-gui QI Zhi-hong PENG Gui-hua LIU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1099-1106,共8页
Pyrochlore-type tungsten oxide (PTO), WO3·0.5H2O, is an emerging material with very wide potential applications. The influences of iron valences and the additive amount of ferrous ion on tungsten crystallization ... Pyrochlore-type tungsten oxide (PTO), WO3·0.5H2O, is an emerging material with very wide potential applications. The influences of iron valences and the additive amount of ferrous ion on tungsten crystallization ratio and the acceleration mechanism of ferrous ion were investigated when PTO was hydrothermally prepared in aqueous ammonium tungstate solution containing ammonium carbonate. The results show that ferrous ion can remarkably accelerate tungsten crystallization while both elemental iron and ferric ion have little influence on the crystallization. Moreover, the tungsten crystallization ratio increases with increasing the amount of ferrous ions added and reaches the maximum of about 60% with ferrous ion concentration of 16 g/L. FTIR analysis of the spent solution after PTO crystallization shows that ferrous ion can accelerate the conversion of WO4 tetrahedral to WO6 octahedron. Combined with XPS and XRD analyses of the hydrothermal product, the acceleration effect of ferrous ion on tungsten crystallization could basically be attributed to the increase in the interplanar spacing of PTO lattice caused by the incorporation of ferrous ion into PTO crystal lattice. The results presented is conducive to the efficient preparation of PTO powder and cleaner tungsten metallurgy. 展开更多
关键词 pyrochlore-type tungsten oxide ammonium tungstate solution ferrous ion CRYSTALLIZATION mechanism
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Adsorption of 2-naphthalenesulfonic acid/sulfuric acid/sulfurous acid from aqueous solution by iron-impregnated weakly basic resin:Equilibrium and model 被引量:1
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作者 Changhai Li Dongmei Jia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第11期1522-1526,共5页
Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the... Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the adsorption behavior of 2-naphthalenesulfonic acid(NSA), sulfuric acid and sulfurous acid from their solution at 298 K onto the novel hybrid iron impregnated D301(Fe-D301). Adsorption affinity of NSA on Fe-D301 was found to be much higher than that of sulfuric acid, while adsorption affinity of sulfuric acid was slightly higher than that of sulfurous acid. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The non-ideal competitive adsorbed model coupled with the single-solute adsorption models were used to predict the bisolute and trinary-solute competitive adsorption equilibria. The NICM coupled with the Langmuir model yields the favorable representation of the bisolute and trinary-solute competitive adsorption behavior. 展开更多
关键词 2-naphthalenesulfonic acid Hybrid iron impregnated D301 Adsorption Non-ideal competitive adsorbed model Model Equilibrium
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