(1. 中南大学 冶金科学与工程学院，长沙 410083；
2. 中南大学 难冶有色金属资源高效利用国家工程实验室，长沙 410083)
摘 要: 测定甘油、苯及二碘甲烷与氧化铝生产中赤泥主要物相之间的接触角，采用Owens二液法估算各物相的表面自由能，分析了赤泥主要物相的表面性质与其沉降性能之间的关系，并讨论针铁矿在高压处理后沉降性能变差的原因。结果表明：甘油−苯和甘油−二碘甲烷测定数据估算的溶剂化趋势按水化石榴石、硅酸二钙、水合铝 硅酸钠、钛酸钙、针铁矿、赤铁矿、石灰石的顺序递减，而其沉降性能与之相反，即溶剂化趋势越小，沉降性能越好。赤泥主要物相中，针铁矿高压处理后转变为赤铁矿，固相粒径变小，溶剂化趋势增加，从而导致其沉降性能恶化。
关键字: 赤泥；表面自由能；Owens二液法；沉降性能；针铁矿
main minerals in red mud on their sedimentation ability
（1. School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China;
2. National Engineering Laboratory for Efficient Utilization of Refractory Non-ferrous Metals Resources,
Central South University, Changsha 410083, China）
Abstract:The contact angles of glycerol, benzene and diiodomethane on the main minerals in red mud from alumina production were measured, and the corresponding surface free energy values were estimated by Owens two liquids method. And then, the relationship between the sedimentation ability of the minerals and their surfacial properties was discussed. Further, the reason for the sedimentation ability of goethite getting worse after high-pressure treatment was also discussed. The results show that the solvent tendency reduces in the following order: hydration garnet, dicalcium silicate, sodium alumino-silicate hydrate (DSP), calcium titanate, goethite, hematite and limestone, while the sedimentation ability tendency is reverse. Less solvent tendency improves their sedimentation. In addition, the sedimentation ability of fresh hematite deteriorates due to the thinning in grain size and the decrease in solvent tendency when goethite changes into hematite in aluminate solution at high pressure.
Key words: red mud; surface free energy; Owens two liquids method; sedimentation ability; goethite
