Investigation of the reaction of boron oxide with aluminium powder and method development for boron determination in the reaction mixture

Abstract

In this study, a cheap method for the synthesis of elemental boron by the reduction of boron oxide with aluminum was investigated. However after various optimization studies, detectable boron amounts could not be found in the reaction mixtures by XRD and SEM-EDX analysis. Meanly aluminum borates were formed as products and these products were leached by 6 M HCl, however removel of borates could not be achieved. We think that the reason of this outcome is that we worked with simple experimental setup, therefore could not achieving the suitable experiment conditions and because of this we failed in the sythesis of boron. In the second part of the study, a new method for the direct determination of boron was investigated. 96 %pure boron and KBr were mixed and analyzed with Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS). No distinct differences for boron was observed in the DRIFT spectra. Then, different sample compositions were prepared with different amounts of boron and KBr. These samples were split as validation and calibration sets and their spectra were collected by DRIFTS. All collected spectral data were processed in a different computer where the data proccessing programs were installed. The genetic inverse least square (GILS) method was used inorder to generate calibration model. Results obtained showed that boron amounts could be directly determined with maximum 3-4 % error. Afterwards, same procedure was also tried for boron and boron oxide binary mixtures and boron, boron oxide and aluminum ternary mixtures. In the binary mixture, determination of boron could be successfully achieved, however boron oxide determination could not be achieved as good as boron determination. In the ternary mixture, better results were obtained compared to binary mixture. Finally, the method was tried with the original samples, but not very satisfactory results were obtained. We think this result is due to the malfunction of FTIR instrument and personal error in the preparation of similar samples. More sample preparation and measurement could not be achieved because the FTIR instrument is not functioning at present.