废弃人造大理石的热解和水解
Jacopo De Tommaso1, Federico Galli2, Tien Dat Nguyen1
1Génie Chimique, Polytechnique Montréal, 2500 ch. de Polytechnique Montréal, Québec, Canada.
Waste management (New York, N.Y.)
|February 7, 2025
概括
回收人工大理石 (PMMA和氧化) 是一个挑战. 热解和水解提供了一个可行的解决方案,回收66%的MMA和有价值的原料前体.
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.
- 可持续化学 可持续化学
背景情况:
- 人工大理石是聚甲基甲烯酸盐 (PMMA) 和氧化 (Al(OH) 3的复合物,广泛使用,但由于交叉链接,难以回收.
- 目前用于人工大理石的回收方法要么是不可能的 (机械),要么是无利可图的 (化学).
- 需要经济可行的回收解决方案,以保持有机和无机成分的价值.
研究的目的:
- 为了研究生命周期结束的人造大理石的热解和水解,以进行价值化.
- 确定最佳条件,最大限度地从人工大理石废物中回收有价值的产品.
- 评估在回收过程中保留无机分量的价值的潜力.
主要方法:
- 在不同温度,水含量,催化剂和加热方式下研究了消费后人工大理石的热解和水解.
- 在热和水解条件下分析了PMMA的分解路径和Al (OH) 3的转化.
- 确定了最佳的加热配置,以最大限度地提高单体回收和无机分量的转化.
主要成果:
- 一个涉及受控加热的双相工艺,从PMMA中获得66%的甲基甲基酸盐 (MMA) 产量.
- 无机分数转化为γ-的前体 (boehmite),剩余的聚合物使能耗自给自足的化.
- 最佳条件包括在300°C的初始水释放,然后在400°C的MMA生产.
结论:
- 热解和水解是人工大理石的可持续和经济可行的回收方法.
- 这一过程有效地回收了有价值的MMA,并保留了无机分量的价值作为的前体.
- 开发的方法解决了这种广泛使用的复合材料的回收挑战.
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