Spent ion exchange resin (SIER) is a by-product derived from drinking water treatment plants, possessing intriguing physicochemical properties that render it a promising ingredient for composite building materials. Surprisingly, there has been a luck of research investigating its impact on the performance of such materials. This study addresses this gap by characterizing unfired and fired gypsum-based composites with varying SIER weight ratios (10–50 wt%) and firing temperatures (300, 600, and 900°C). X-ray diffraction, scanning electron microscopy, and the hot disk method were employed to explore the effects of SIER on the composites’ thermal-mechanical features. The results revealed the significance of SIER as a promising waste-based aggregate to enhance the specific heat capacity () of gypsum-based composites. With increasing SIER content and firing temperature, the composites demonstrate improved c, reduced thermal conductivity, and decreased compressive strength. Both unfired and fired composites exhibited an increase in , up to 74.4% and 331.8%, respectively. The composite material achieved a noteworthy reduction in thermal conductivity, reaching 0.132 W/m.K, and a specific heat capacity increase to 4491.35 J/kg.K, which surpasses that of the control sample by more than four times (1040 J/kg.K). These newly developed composites hold significant promise as thermal energy storage materials for low-temperature building applications.

中文翻译：

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废离子交换树脂作为新型骨料提高复合建筑材料比热容：以石膏为例

废离子交换树脂 (SIER) 是饮用水处理厂的副产品，具有令人着迷的物理化学特性，使其成为复合建筑材料的一种有前途的成分。令人惊讶的是，有很多研究调查了它对此类材料性能的影响。本研究通过表征具有不同 SIER 重量比（10-50 wt%）和烧制温度（300、600 和 900°C）的未烧制和烧制石膏基复合材料来解决这一差距。采用X射线衍射、扫描电子显微镜和热盘法探讨了SIER对复合材料热机械特性的影响。结果揭示了 SIER 作为一种有前途的废物基骨料对于提高石膏基复合材料的比热容 () 的重要性。随着 SIER 含量和烧成温度的增加，复合材料的 c 值提高，导热率降低，压缩强度降低。未烧制和烧制复合材料的 增幅分别高达 74.4% 和 331.8%。该复合材料的导热系数显着降低，达到0.132 W/mK，比热容增加至4491.35 J/kg.K，比对照​​样品（1040 J/kg.K）高出四倍多）。这些新开发的复合材料作为低温建筑应用的热能存储材料具有巨大的前景。