Work

Utilizing Taguchi method and in situ X-ray powder diffraction monitoring to determine the influence of mechanical activation conditions on the physico-chemical properties and Al leachability of K-feldspar

Year: 2024

Type: article

Abstract: The present study has shown the possibility to recover Al from K-feldspar by applying the tools of high-energy ball milling, which resulted in the mechanical activation. The effect of sample mass, milling time and milling speed on specific surface area, particle size distribution, mineral phases amorphization and Al recovery was assessed via the Design of Experiments methodology, namely by using the L9 (44) Taguchi orthogonal array. The results showed that amorphization of the identified phases, namely that of microcline, is directly related to the observed Al recovery, with particle size reduction and specific surface area increase being much less important. By means of Analysis of Variance, it was proven that the ball-to-powder ratio is the most important factor contributing to Al recovery, followed by milling speed and milling time. It was also possible to derive regressions that make it possible to predict the Al recovery once knowing either the mentioned milling parameters or the median particle size (d50), specific surface area and microcline amorphization. The in situ X-ray diffraction monitoring has shown very rapid amorphization of microcline to some extent after which the amorphization process almost completely stopped. The results also showed the less intensive effect of the oscillation ball milling in comparison with the planetary ball milling. The present contribution shows that upon application of high-energy milling treatment without the oxidative roasting, it is possible to reach almost quantitative recovery of aluminum, mainly due to the strong impact on the crystalline structure of the minerals containing the targeted metal.

Source: Journal of Materials Research and Technology

DOI: 10.1016/j.jmrt.2024.08.156