Advances in Molten Slags, Fluxes, and Salts - Proceedings of the 10th International Conference on Molten Slags, Fluxes and Salts
Advances in Molten Slags, Fluxes, and Salts - Proceedings of the 10th International Conference on Molten Slags, Fluxes and Salts
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熔渣、熔剂和盐的进展 - 第十届熔渣、熔剂和盐国际会议论文集
DOI：
10.1002/9781119333197.ch7
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Escudero-Castejon L
中科院分区：
文献类型：
--
作者：
Escudero-Castejon L
从铬铁矿中提取铬是基于矿物的氧化碱焙烧形成水溶性碱金属铬酸盐。以前的研究报告形成一个熔融的Na 2CO 3-Na 2CrO 4二元混合物焙烧过程中的铬铁矿与碳酸钠。Na 2CO 3-Na 2CrO 4液相的物理性质取决于温度、炉料和脉石组成，在氧化反应中起着重要作用，并可能通过阻碍氧向反应界面的传递而限制铬的回收。分析了碱比对铬提取率的影响，并对两种氢氧化物的提取结果进行了比较。通过样品表征和相图分析，研究了不同焙烧条件下熔盐相的形成及其对铬回收率的影响。
The extraction of chromium from chromite ore is based on the oxidative alkali roasting of the mineral forming water-soluble alkali chromates. Previous investigations reported the formation of a molten Na2CO3-Na2CrO4binary mixture during roasting of chromite with sodium carbonate. The physical properties of the Na2CO3-Na2CrO4liquid phase, which are dependent on temperature, charge and gangue composition, play an important role in the oxidation reaction and may limit the chromium recovery by hindering the oxygen transport to the reaction interface.This investigation focuses on the alkali roasting of chromite ore at 1000°C using NaOH and KOH, and subsequent water leaching. The influence of the alkali ratio on the chromium extraction yield is analysed, and the results obtained with both hydroxides are compared. The formation of molten salt phase under different roasting conditions and its effect on chromium recovery is studied by means of sample characterization and phase diagram analysis.