煤气化细渣超微粉体的制备及其相容性

Preparation and compatibility of ultrafine powder from coal gasification fine slag

以7个地区的煤气化细渣为原料制备超微粉体,研究球磨时间对超微粉体的粒度和比表面积、微观形貌、物相组成的影响,并探讨超微粉体在水、正己烷、丙酮3种溶剂环境中的相容性。结果表明:当球磨时间为1~3 h时所得超微粉体的粒度变化明显,3~4 h内粒度变化趋于平缓,粒度逐渐减小到2~3μm;随着粒度的减小,超微粉体的比表面积逐渐增加,球磨4 h后,大多数煤气化细渣样品所制备的超微粉体的比表面积可达890 m^(2)/kg;随着球磨时间的延长,细渣粒度变小,较多的球形颗粒转变为无规则、有棱角的颗粒;超微粉体的晶相强度减小,衍射峰宽度增大,具有更高的反应活性;超微粉体在水相、正己烷相和丙酮相中的相容性不同,这是由各种超微粉体颗粒Zeta电位、比表面积、颗粒间多孔结构的疏松程度、粉体活性等不同导致的。

Ultrafine powder was prepared from coal gasification fine slag from 7 regions. The effects of ball milling time on particle size and specific surface area, microstructure and phase composition of ultrafine powder were studied. The compatibility of ultrafine powder in water, n-hexane and acetone was also discussed. The results show that the particle size of ultrafine powder obtained by ball milling from 1 h to 3 h changes obviously, and the particle size changes gradually to about from 2 μm to 3 μm within from 3 h to 4 h. With the decrease of particle size, the specific surface area of ultrafine powder increases gradually. After milling for 4 h, the specific surface area of ultrafine powder prepared from most coal gasification fine slag samples can reach 890 m^(2)/kg. With the prolongation of ball milling time, the particle size of fine slag becomes smaller and more spherical particles become irregular and angular particles. The crystal phase intensity of ultrafine powder decreases, the diffraction peak width increases and it has higher reactivity. The compatibility of ultrafine powder in water phase, n-hexane phase and acetone phase is different, which is caused by the difference of Zeta potential, specific surface area, porosity of porous structure between particles and activity of ultrafine powder.