能效利用循环流化床飞灰制备-复合物气凝和石膏
Jia-Yong Li1, Bao-Hua Tian2, Xin-Xin Li2
1College of Biomedical Engineering, Taiyuan University of Technology, 209 University Street, Jinzhong, Shanxi 030600, China; College of Environmental Science and Engineering, Taiyuan University of Technology, 209 University Street, Jinzhong, Shanxi 030600, China.
Waste management (New York, N.Y.)
|November 2, 2023
概括
循环流化床灰 (CFA) 是合成Si-Al气凝和石膏的成本效益高的前体. 这种新的方法减少了能源消耗和浪费,为建筑应用提供了具有出色绝热性能的材料.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 环境科学 环境科学
背景情况:
- 传统的Si-Al气凝合成是昂贵且耗费大量能源的.
- 利用流动化床飞灰 (CFA) 等废物提供了一个可持续的替代方案.
- 挑战包括当前方法的高能耗和二次废物产生.
研究的目的:
- 开发一种节能且无浪费的技术,将CFA转化为Si-Al气凝.
- 为了优化生产具有理想性质的Si-Al气凝的过程.
- 评估CFA衍生的Si-Al气凝和石膏在建筑应用中的潜力.
主要方法:
- 通过用Na2CO3烧结CFA而制备Si-Al sol,然后通过硫酸洗.
- 使用sol-gel方法合成Si-Al气凝,使用trimethyl chlorosilane修饰和环境压力干燥.
- 优化烧结温度和前体比率,并对产生的材料进行表征.
主要成果:
- 对CFA和Na2CO3 (质量比为0.7) 的最佳烧结温度确定为750°C.
- CaSO4·0.5H2O 满足建筑石膏标准,在126°C生产2小时.
- 修改后的Si-Al气凝实现了高特异性表面积 (857 m2/g) 和疏水性 (139.3°).
结论:
- 开发的技术提供了一种有效的,低能耗和无浪费的途径,可以从CFA中生产Si-Al气凝.
- 来自CFA的Si-Al气凝和石膏显示出有前途的隔热和机械性能.
- 这些材料在建筑行业具有可持续应用的潜力.
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