Synthesis of pure potassium pentaborate (KB5) from potassium dihydrogen phosphate (KH2PO4) and colemanite

Abstract

In this study, after specifying theoretical reaction conditions required for chemical reaction, potassium pentaborate (KB5) was synthesized from the potassium dihydrogen phosphate (KH2PO4) solution and the raw colemanite (Ca2B6O11.5H2O) ore. The slow evaporation solution method was used at 25 ℃. The effect of time (6-18 hours) on crystallization was studied. Synthesized minerals were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR), RAMAN spectroscopies, and scanning electron microscopy (SEM). The results according to the XRD, FT-IR, RAMAN, and SEM analyses proved that the synthesized product was the potassium pentaborate (KB5O8.4H2O) mineral having the ICSD: 96-026-1927 pdf code. As a result, the cost was reduced by using raw boron ore, colemanite and KB5 could be obtained in a shorter time and at a lower temperature.