Zhang Yingda, Tang Zhaopeng, Zhou Xianliang, Zheng Yantao, Liu Zihao
School of Architecture and Civil Engineering, Xihua University, Chengdu, 610039, China.
Guizhou Chengqian Mining Development Co., Ltd, Guiyang, 551000, China.
Sci Rep. 2025 Aug 17;15(1):30115. doi: 10.1038/s41598-025-16048-8.
This study investigated the effects of NaOH molarity (6-14 M) and ground granulated blast furnace slag (GBFS) content (0-45%) on the properties of lithium slag (LS)-based cold-bonded lightweight aggregates. Bulk density, water absorption, porosity, and cylinder compressive strength were evaluated, and microstructural characterization was conducted using SEM, XRD, FTIR, MIP, and TG/DTG. Results showed that increasing NaOH molarity and GBFS content reduced water absorption (from 15.87 to 5.88%) and porosity (from 34.79 to 13.39%), while enhancing bulk density (731-1074 kg/m³) and compressive strength. At 30% GBFS, the 28-day strength increased by 224.48%, from 3.35 MPa (M6-30) to 10.87 MPa (M14-30). At 12 M NaOH, raising GBFS content from 0 to 45% increased strength by 435.62%, from 2.33 MPa to 12.48 MPa. LS without GBFS achieved 2.33 MPa, indicating inherent pozzolanic activity. Microstructural analysis revealed that performance improvement was due to enhanced geopolymerization and reduced harmful pores (> 200 nm). The M8-30 mix (915.68 kg/m³, 5.98 MPa) showed potential for meeting high-strength lightweight aggregate criteria with mix optimization. These findings demonstrate the feasibility of valorizing LS into high-performance lightweight aggregates, contributing to waste utilization and low-carbon construction.
本研究调查了氢氧化钠摩尔浓度（6 - 14M）和磨细粒化高炉矿渣（GBFS）含量（0 - 45%）对锂渣（LS）基冷粘结轻质集料性能的影响。评估了堆积密度、吸水率、孔隙率和圆柱体抗压强度，并使用扫描电子显微镜（SEM）、X射线衍射仪（XRD）、傅里叶变换红外光谱仪（FTIR）、压汞法（MIP）和热重/微商热重分析（TG/DTG）进行微观结构表征。结果表明，增加氢氧化钠摩尔浓度和GBFS含量可降低吸水率（从15.87%降至5.88%）和孔隙率（从34.79%降至13.39%），同时提高堆积密度（731 - 1074千克/立方米）和抗压强度。在GBFS含量为30%时，28天强度提高了224.48%，从3.35兆帕（M6 - 30）增至10.87兆帕（M14 - 30）。在氢氧化钠浓度为12M时，将GBFS含量从0提高到45%，强度提高了435.62%，从2.33兆帕增至12.48兆帕。不含GBFS的LS达到了2.33兆帕，表明其具有潜在的火山灰活性。微观结构分析表明，性能的改善归因于地聚合反应的增强和有害孔隙（>200纳米）的减少。M8 - 30混合料（915.68千克/立方米，5.98兆帕）显示出通过混合料优化满足高强度轻质集料标准的潜力。这些发现证明了将LS转化为高性能轻质集料的可行性，有助于废物利用和低碳建筑。
