黏土钒矿直接常压活化酸浸提钒热力学分析

目前黏土钒矿直接酸浸的试验以及基础性研究较少，为了进一步推动此类问题的研究进展，本项研究采用试验结合热力学计算的方法，通过试验得到了最佳浸出剂结果，运用热力学计算诠释了活化浸出钒过程的热力学行为以及其机理，同时进一步分析了不同硫元素的总量对酸浸液中各组分的影响，为从酸浸液中提钒工艺进行了溶液化学分析。结果表明：二氧化锰有能力将低价钒氧化至高价钒，从而提升钒的浸出率，升高温度对浸出率的提高以及二氧化锰的氧化均会造成不利影响，但是会抑制杂质的浸出，对杂质分离起到积极影响。硫酸的用量一方面会影响浸出过程的pH，同时会影响酸浸液中各组分的含量，低硫的酸浸体系与高硫体系中钒的离子形态存在差异。低硫体系中铁杂质的溶解度会小于高硫体系，有利于提钒过程中杂质的分离。通过分析浸出过程中溶液组分的变化，可以为后续提钒工序提供理论依据。

Analysis of thermodynamics of vanadium extraction from clay vanadium ore by direct atmospheric pressure activation

At present, there are few experiments and basic researches on direct acid leaching of clay vanadium ore. In order to further promoted the research progress of this kind of problem, the method of experiment combined with thermodynamic calculation was adopted in this study. The results of the best leaching agent were obtained through experiments. The thermodynamic behavior and mechanism of vanadium leaching process were explained by thermodynamic calculation. The influence of total amount of different sulfur elements on the components of acid leaching solution was further analyzed. The solution chemical analysis was carried out for vanadium extraction process from acid leaching solution. The results showed that manganese dioxide has the ability to oxidize low valence vanadium to high valence vanadium, so as to improve the leaching rate of vanadium. The increase of temperature will have adverse effects on the improvement of leaching rate and the oxidation of manganese dioxide, but it will inhibit the leaching of impurities and have a positive impact on the separation of impurities. The amount of sulfuric acid not only affect the pH of the leaching process, but also affect the content of each component in the acid leaching solution. The solubility of iron impurities in the low sulfur system is lower than that in the high sulfur system, which is conducive to the separation of impurities in the process of vanadium extraction. By analyzing the change of solution components in the leaching process, the theoretical basis can be provided for the subsequent vanadium extraction process.