Impurity Control in Boric Acid Leaching: A Review of Challenges and Strategies

İngilizce (OpenAlex)

Abstract Boron minerals, which are hydrated borate compounds of alkali and alkaline earth metals such as Na, Ca, and Mg, contain impurities including clay minerals, calcite, dolomite, gypsum, realgar, orpiment, iron oxide, and sulphur. Boric acid, produced from boron minerals, is the most widely used chemical in the industry as it is used as a raw material in the manufacture of various specific boron products. Boron products are among the most commonly utilised materials today, owing to properties such as resistance to chemical effects, light-weight structure, high mechanical strength, and thermal stability. During the production of boric acid, if the impurities in the boron minerals are not controlled due to the different leach reagents used, filtration difficulties will occur in the later stages of the process. Therefore, the purity and yield of boric acid will be adversely affected, and environmental pollution will occur. The most difficult impurities among these are calcium and magnesium. A review of the literature reveals that many leaching studies have been conducted without adequate consideration of such impurities, leading to the aforementioned issues. In studies where impurities were considered, it has been determined that parameters such as reaction time, temperature, solid/liquid ratio, particle size, mixing speed, and acid concentrations significantly influence the presence of calcium and magnesium, as well as the overall quality of boric acid. With this literature review, the remarkable results obtained from many studies on impurities will be compiled into a single article. Thus, it is believed that researchers working on the subject will be greatly facilitated by the information gathered in this review, enabling them to obtain products with higher purity and more environmentally friendly by-products. Graphical Abstract