This study deals with magnesium oxychloride- (MOC-) based construction composites in which, a filler formed from end-of-life MOC-based composite recyclate is used as a partial or full replacement of standard quartz sand filler. The developed composites pose as a highly environmentally sustainable alternative to Portland cement (PC), which has dominated the global construction sector, largely due to its unique properties and adaptability to various conditions. As the PC industry is a major contributor to greenhouse gas emissions, it is ultimately necessary to find a suitable alternative. In our study, we demonstrated that the proposed composite, even with a very high content of the MOC-based recyclate performs well concerning its mechanical parameters evidenced by compressive strength exceeding 64 MPa. The developed composites also yield a low water absorption of about 3.3 wt% and even when exposed to the harsh environment of 95 % RH for 7 days, their softening coefficient reaches values higher than 85 %. The acquired material parameters of the prepared composites make them suitable for application in the production of construction materials with high mechanical strength and acceptable resistance to the action of moisture. The approach which was taken, where MOC-based construction waste can be fully reutilized in the next generation of MOC composites as a filler represents a very promising route for the development of waste-free and CO2-neutral technology.

中文翻译：

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氯氧镁水泥的回收利用：粉碎的MOC废料作为填料在下一代MOC复合材料中的应用


本研究涉及氯氧化镁 (MOC) 基建筑复合材料，其中使用由报废 MOC 基复合材料回收物形成的填料来部分或完全替代标准石英砂填料。所开发的复合材料是波特兰水泥（PC）的高度环境可持续的替代品，后者在全球建筑领域占据主导地位，这主要是由于其独特的性能和对各种条件的适应性。由于PC行业是温室气体排放的主要贡献者，因此最终有必要找到合适的替代品。在我们的研究中，我们证明了所提出的复合材料，即使基于 MOC 的回收物含量非常高，其机械参数也表现良好，其抗压强度超过 64 MPa。所开发的复合材料还具有约 3.3 wt% 的低吸水率，即使暴露在 95% RH 的恶劣环境下 7 天，其软化系数也达到高于 85% 的值。所制备的复合材料获得的材料参数使其适合用于生产具有高机械强度和可接受的耐湿性的建筑材料。所采取的方法是，基于 MOC 的建筑废物可以在下一代 MOC 复合材料中作为填料得到充分再利用，这代表了开发无废物和二氧化碳中性技术的一条非常有前途的途径.