在水泥中形成的五价的形成动力学和反应行为,共同处理固体废物
Bingying Gao1, Haohao Jiang2, Wenyi Zhang2
1School of Petrochemical Engineering, Changzhou University, Changzhou 213164, China.
The Science of the total environment
|September 13, 2023
概括
这项研究研究了一种新型的五价化合物,该化合物是在水泥的共同加工过程中形成的. 了解其形成,溶解度和氧化还原反应对于管理含的危险废物至关重要.
科学领域:
- 环境科学 环境科学
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
背景情况:
- 混凝土炉联合处理是处理危险废物,特别是含 (Cr) 的废物的一种关键方法.
- 一种新发现的五价 (Cr(V)) 化合物有助于水溶性Cr从水泥中释放出来.
- 这种Cr(V) 化合物的形成动力学和溶解性仍然不太清楚.
研究的目的:
- 在高温下研究Cr(V) 化合物的形成特征和反应动力学.
- 确定Cr (V) 化合物的晶体结构和可溶性.
- 探索Cr(V) 化合物在不同温度下的氧化还原反应.
主要方法:
- 高温实验检查反应动力学和氧化还原反应.
- 用X射线衍射进行晶体结构识别.
- 在不同温度的中性水中进行溶解性试验.
主要成果:
- 在1000-1200°C时,CrV化合物Ca5CrO4) 3O0.5迅速形成 (>90%在10分钟内),形成动力学从接口反应转向扩散控制.
- Ca5(CrO4)3O0.5被确定为一个六边形的水晶 (P63/m).
- 观察到明显的溶解度,度在100°C时达到550 mg/L,在50°C时达到150 mg/L.
- 观察到的还氧反应是:氧化为CaCrO4 (400-700°C) 和转化为Ca3(CrO4) 2,并减少为CaCr2O4 (>1400°C).
结论:
- 该研究阐明了水泥共加工中的关键Cr(V) 化合物的形成,结构,可溶性和高温氧化还原行为.
- 这些发现为在废物热处理过程中的行为提供了重要的见解.
- 结果为优化危险废物管理策略和减轻与相关的环境风险提供了宝贵的指导.
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