碳化处理对钢渣聚合物的性能的影响
Jian Ma1,2, Guangjian Dai1, Feifei Jiang2,3
1College of Architecture and Civil Engineering, Jiangsu University of Science and Technology, Zhenjiang 212000, China.
Materials (Basel, Switzerland)
|September 9, 2023
概括
用二氧化碳加碳的钢渣聚合物通过减少膨胀和增加强度来提高其性能. 最佳方法涉及72小时的55°C,增强聚合物的稳定性并使碳捕获成为可能.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 环境科学 环境科学
背景情况:
- 钢铁,是钢铁炼的副产品,具有固性质,但由于膨胀可能导致混凝土损坏.
- 未经处理的钢渣聚合物表现不佳,特别是在高压固化后,导致结构完整性问题.
研究的目的:
- 为了研究碳化对钢渣聚合物的性能和稳定性的影响.
- 优化碳化条件,以提高聚合物性能,并评估碳捕集效率.
主要方法:
- 使用钢渣,飞灰和水泥制备有孔状聚合物.
- 在高压CO2条件下 (0.2MPa) 在不同温度和持续时间下碳化聚合物.
- 通过体积稳定性和粉碎值测试来评估性能.
- 微结构分析使用X射线衍射 (XRD) 和热重力测量 (TG) 分析.
主要成果:
- 未经处理的钢的自闭柜固化导致完全破坏和强度损失.
- 碳化显著改善了聚合物的性能,降低了粉碎,膨胀和粉碎值.
- 最佳的碳化条件被确定为55°C72小时.
- 碳化导致CaCO3的形成,填充毛孔并增强聚合物的稳定性.
结论:
- 二氧化碳碳化是一种有效的方法,可以提高钢渣聚合物的性能和稳定性.
- 从自由氧化 (f-CaO) 和二氧化碳中形成碳酸 (CaCO3) 是提高性能的主要机制.
- 优化的碳化处理实现了粉碎率为2.4%,膨胀率为0.23%,粉碎值为23%,碳封存效率为11.27%.
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