Growth of Abraded Crystals Tracked in Three Dimensions

Abstract

The interaction between crystal growth and abrasion is essential during crystallization. Although each of these phenomena has been independently studied in the literature in detail, their interaction is not well understood. Here, we present a method to track the growth of abraded potash alum crystals in three dimensions. The method is based on micro-computed tomography. This technique distinguishes between different growth domains in three dimensions and is used to track the growth of crystal faces and abraded regions. We observed how abraded regions grew faster than crystal faces. Therefore, growth leads to ideally facetted crystals. Further, growth rates in all directions were derived and used to parametrize a growth model. The model is able to describe the size and shape evolution of abraded potash alum crystals in three dimensions.

Nucleation and Growth Kinetics of Sodium Chloride Crystallization from Water and Deuterium Oxide

“…The discrepancy in the measured growth rate is likely to be exacerbated by the greater degree of agitation typically produced in magnetic stirring compared to the quiescent and fluidised bed conditions of previous publications, as supported by the observation that we indeed measure lower rates in gentler overhead stirring conditions, and at intermediate S, overhead stirring measurements agree reasonably with the literature. Damage to crystals particularly in magnetic stirring conditions is a possible factor linked to agitation, and damaged crystal surfaces have been observed to grow faster [68,69] which would lead to higher observed rates. While the use of overhead stirring in seeded conditions avoids such damage to the seed itself, the growing secondary crystals whose size distribution generates our growth rate estimate are still vulnerable to attrition and fragmentation as they impact the vessel and the impeller, and one would expect the consequences of this to be more severe in systems of brittle crystals such as NaCl.…”

Online 3D Characterization of Micrometer‐Sized Cuboidal Particles in Suspension

“…[3][4][5] To describe both size and shape, at least two characteristic lengths are needed, which can be obtained through a number of 2D or 3D characterization techniques. [6][7][8][9] Such (offline and online) techniques, including micro-computed tomography (µCT), [10][11][12][13][14][15][16][17] holography, [18][19][20] structural light, [21] machine vision, [13,[22][23][24][25][26][27][28][29][30][31] confocal microscopy, [32] and surface imaging [33] have varying degrees of accuracy and complexity. Machine vision through image analysis (IA) has become an increasingly powerful tool, due to experimental simplicity, hardware improvements, and continual increases in available computational power.…”