查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0085" view="all">The carbothermic reduction behavior of original ilmenite and pre-oxidized ilmenite concentrates were investigated by a non-isothermal method using a thermogravimetry facility. The reaction degree was calculated using the tail gas composition and the Starink method to analyze the activation energy of the reduction. The results demonstrated that trends of different reaction degree curves are similar under the same conditions. The average activation energy of the pre-oxidized ilmenite concentrate was less than that of the original form by approximately 25%, and the starting reduction temperature was lower by 67K than that of the original ilmenite concentrate. However, the reduction time of the pre-oxidized ilmenite concentrate was longer than that of the original ilmenite concentrate for the same reaction degree; therefore, a slow reduction rate for the oxidization sample was observed. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersion spectroscopy (EDS) were used to characterize the phase and micro-morphology of the two raw materials and compare the reduction products.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0090" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">Both the phase transition and microstructure transition of original and pre-oxidized ilmenite concentrate were compared.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">Clarifying the influence of pre-oxidation on the reduction of ilmenite concentrate with carbon, both thermodynamically and kinetically.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">The tail gas engendered from the chemical reaction was detected in real-time, and analyzed in detail in the paper.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
查看更多>>摘要：<![CDATA[<ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0005" xml:lang="en" view="all" class="author"><ce:section-title id="st0005">Abstract</ce:section-title><ce:abstract-sec id="as0005" view="all"><ce:simple-para id="sp0020" view="all">Fractional calculus is a generalization of the traditional calculus approach. In this research, column leaching test results are modeled by using the rate equation obtained by fractional calculus and compared to the traditional mass transfer equation model. By analyzing the adjusted determination coefficient, it is demonstrated that the proposed fractional model describes the extracted recovery percentage better than traditional equations. This analysis supports the utilization of the new model without over-parameterization. The present work brings a new point of view in mass transfer modelling of column leach testing, and therefore reformulates the existing models based on classic transport phenomena, leading to better understanding of the mineral leaching process.</ce:simple-para></ce:abstract-sec></ce:abstract><ce:abstract xmlns:ce="http://www.elsevier.com/xml/common/dtd" xmlns="http://www.elsevier.com/xml/ja/dtd" id="ab0010" class="author-highlights" xml:lang="en" view="all"><ce:section-title id="st0010">Highlights</ce:section-title><ce:abstract-sec id="as0010" view="all"><ce:simple-para id="sp0025" view="all"><ce:list id="l0005"><ce:list-item id="li0005"><ce:label>?</ce:label><ce:para id="p0005" view="all">New mathematical description of leaching column testing assays based on fractional calculus is proposed.</ce:para></ce:list-item><ce:list-item id="li0010"><ce:label>?</ce:label><ce:para id="p0010" view="all">The mathematical description of leaching process is improved by generalization of transport phenomena using fractional calculus.</ce:para></ce:list-item><ce:list-item id="li0015"><ce:label>?</ce:label><ce:para id="p0015" view="all">The Fickian model overestimates the required time for 90% metal recovery while fractional model is statistically consistent.</ce:para></ce:list-item></ce:list></ce:simple-para></ce:abstract-sec></ce:abstract>]]>
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