硼泥活化焙烧-浸取综合回收硅、镁有价组分

以硼化工行业固体废物--硼泥为原料，在TG-DSC热分析基础上，采用马弗炉和微波炉对其进行活化焙烧，再将焙烧产物进行碱浸和酸浸综合回收硅、镁有价组分。研究了两种焙烧方式对硼泥中SiO₂和MgO浸出率的影响。采用化学分析、X射线衍射和扫描电镜对焙烧产物以及白炭黑和氧化镁制品的化学成分、物相组成和微观形貌进行表征分析。结果表明：两种焙烧方式均可提高硼泥活性，促进硼泥中硅、镁组分的浸取。其中，马弗炉最佳焙烧条件为600℃、30 min，此时硼泥中SiO₂和MgO浸出率分别为97.65%和98.81%；微波炉最佳焙烧条件为500℃、10 min，此时SiO₂和MgO浸出率分别为98.03%和98.83%。白炭黑制品中SiO₂含量为92.20%，颗粒多呈近球状，粒径100～200 nm。氧化镁制品中MgO含量为93.05%，晶粒呈圆片状，粒径约2 mm。

Extraction of valuable Si and Mg components from boron mud by roasting-leaching

Based on TG-DTA analysis, boron mud, the solid waste of boron chemical industry, was roasted in a muffle oven and a microwave furnace at different temperatures, and the roasted products were processed through alkaline leaching and acid leaching to extract separately valuable Si and Mg components. The effects of roasting methods and temperature on leaching rates of SiO₂ and MgO were investigated. Chemical and phase compositions as well as micro-structures of the roasting products, obtained silica and magnesium oxide were analyzed and characterized by chemical analysis, XRD and SEM. The results indicate that the activity of the boron mud increases after both two types of roasting. The optimal process parameters are 600℃ and 30 min for the roasting in muffle oven and 500℃ and 10 min for doing in microwave furnace. At these conditions, the leaching rates of SiO₂ and MgO reach 97.65% and 98.81% for former and 98.03% and 98.83% for later, respectively. The silica prepared, containing 92.20% SiO₂, consists of nearly spherical grains with diameter ranges from 100 to 200 nm. And the magnesium oxide obtained, containing 93.05% MgO, makes of plate-like grains with diameter about 2 mm.