Synthesis of calcium hexaboride from synthetic colemanite by mechanochemical method

In this study, the economical synthesis of calcium hexaboride (CaB6), a valuable boron end product from the alkaline earth metal borides class, was studied. Metal borides are named according to the boron / metal ratio in their formulas and are classified in two classes as metal-rich and boron-rich. As a result of the interaction of many metals with boron, a wide variety of binary compounds are formed. MB6 phase is the most stable of metal borides because it is formed as a result of the reaction of appropriate amount of boron and metal in all cases. CaB6 is an example. CaB6 is a boron product with refractory properties and also a valuable intermediate product that can be used as a reagent in the synthesis reaction of advanced end boron products. In the study, calcium hexaboride synthesis was carried out using dehydrated colemanite and without the need for high temperature as in the carbothermal method, without the need for any intermediate step or intermediate product. The absence of expensive reagents and high process requirements made it possible to achieve this synthesis in an economical way. FT-IR and XRD analysis were used in the characterization of the product. In XRD diffraction patterns, it was also observed that calcium oxide peaks, which are byproducts according to the proposed reaction, exist, as can be seen from the peaks belonging to the synthesized calcium hexaboride. The characterized product was purified at 900°C, burned in the ash furnace and FT-IR analysis was performed.