Effect of B2O3 on the viscosity and structure of yellow phosphorus slag melt

作者：Zheng, Dingli; Zhu, Junlin; Ma, Guojun^*; Zhang, Xiang; Liu, Mengke

来源：Journal of Non-Crystalline Solids, 2022, 590: 121693.

DOI：10.1016/j.jnoncrysol.2022.121693

• Yellow phosphorus slag
• Viscosity
• Structure
• B2O3

To improve the fluidity of yellow phosphorus slag in the centrifugal granulation process, the effect of B2O3 on the viscosity and structure of slag were investigated. The results showed that adding B2O3 from 0 to 6.22 wt% reduced the slag viscosity monotonically, which would improve the fluidity of slag. The B2O3 addition reduced the activation energy for viscous flow of slag. With B2O3 addition, the relative fractions of Q(Si)(0) and Q(Si)(1) structure units decreased, and those of structure units Q2(Si), Q(Si)(3) and Q(Si)(4) increased, resulting in the increased polymerization degree of silicate structure. The slag viscosity decreasing with B2O3 addition was because that the introduced B-O bond weaken the connectivity of the network structure, and the dominantly introduced [BO3]-trihedral was simpler than the three dimensional [SiO4]-tetrahedral and [BO4]-tetrahedral. The decreasing proportion of [BO3]-trihedral and increasing proportion of [BO4]-tetrahedral in B-related structure units inhibited the decreasing tendency of slag viscosity.