Extraction of Magnesia from Egyptian Serpentine Ore via Reaction with Different Acids. II. Reaction with Nitric and Acetic Acids
Extraction of Magnesia from Egyptian Serpentine Ore via Reaction with Different Acids. II. Reaction with Nitric and Acetic Acids
复制标题
通过与不同酸反应从埃及蛇纹石矿石中提取氧化镁。
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
M. M. Abd
中科院分区：
文献类型：
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作者：
M. Fouda;R. E. Amin;M. M. Abd
The results of a kinetic study of the dissolution of magnesia from Egyptian serpentine ore with nitric and acetic acids are presented. The effects on the magnesia dissolution of (a) temperature ranging from 30 to 105 °C, (b) time ranging from 2.5 min to several days, and (c) molal ratios between one of the acids and MgO in the ore ranging from 4.42 to 3.86, are presented. From the analysis of the dissolution rate on the basis of a core model, it was found that dissolution rate of MgO could be well expressed by a rate equation based on the rate-limiting step of the surface chemical reaction. The apparent activation energies were ca. 17.4 and 8.3 kcal mol−1 for nitric and acetic acid respectively. The high activation energy of reaction with nitric acid was found to be associated with relatively higher values of activation entropy (ΔS* = −19.5 cal mol−1 K−1), whereas the relatively low activation energy of reaction with acetic acid is associated with negative values of entropy of activation (ΔS* = −44.3 cal ...
