Delgado-Plana Pedro, Bueno-Rodríguez Salvador, Pérez-Villarejo Luis, Eliche-Quesada Dolores
Department of Chemical, Environmental, and Materials Engineering, Higher Polytechnic School of Jaén, University of Jaén, Campus Las Lagunillas S/N, 23071, Jaén, Spain.
Centre for Advanced Studies in Earth Sciences, Energy and Environment (CEACTEMA), University of Jaén, Campus Las Lagunillas, S/N, 23071, Jaén, Spain.
Environ Sci Pollut Res Int. 2024 May 2. doi: 10.1007/s11356-024-33368-w.
Alkali activated materials (AAMs) commonly known as geopolymers are considered ecofriendly substitutes for Portland cement. However, these materials still have a significant environmental impact, owing mainly to the use of activators based on commercial chemical products. In this sense, this research focuses on the production and use of waste glass-derived activators AAMs as an alternative to commercial activators. Using a thermochemical synthesis method, activator compositions were systematically designed to achieve predefined activator modulus (Ms = SiO/NaO = 0.5; 1.0 and 1.5). These alternative activators were studied by XRD, FTIR and SEM techniques. Additionally, one-part AAMs were manufactured using spent oil filtration earth (SOFE) as precursor and activator with optimum modulus Ms = 1.0. The influence of the NaO dosage was studied (10; 20 and 30 g of NaO per every 100 g of SOFE) as well as the influence of the activator modulus maintaining the optimum dosage of 20 g NaO per 100 g of SOFE. As a control, two-part AAMs were also synthetized with the optimum dosage and modulus employing commercial activators (NaOH + NaSiO solution). Results indicate that the modulus of the alternative activator and especially the NaO dosage have a significant influence on the technological properties of AAMs based in SOFE, with an optimum compressive strength (35.8 MPa) for the addition of 20 g of NaO per every 100 g of SOFE using activator with modulus Ms = 1.0. This research embodies a sustainable approach to AAM production and suggests waste glass as a valuable raw material for sodium silicate synthesis intended for the one-part activation of spent filtering earth from the agri-food industry, aligning with the principles of circular economy and sustainable development goals.
碱激活材料（AAMs）通常被称为地质聚合物，被认为是波特兰水泥的环保替代品。然而，这些材料仍然具有重大的环境影响，主要是由于使用了基于商业化学产品的激活剂。从这个意义上说，本研究重点关注废玻璃衍生激活剂AAMs的生产和使用，以替代商业激活剂。采用热化学合成方法，系统设计激活剂组成以实现预定义的激活剂模量（Ms = SiO/NaO = 0.5；1.0和1.5）。通过XRD、FTIR和SEM技术对这些替代激活剂进行了研究。此外，使用废油过滤土（SOFE）作为前驱体和具有最佳模量Ms = 1.0的激活剂制备了单组分AAMs。研究了NaO用量（每100 g SOFE中10；20和30 g NaO）的影响以及保持每100 g SOFE中20 g NaO最佳用量时激活剂模量的影响。作为对照，还使用商业激活剂（NaOH + NaSiO溶液）以最佳用量和模量合成了双组分AAMs。结果表明，替代激活剂的模量，尤其是NaO用量，对基于SOFE的AAMs的技术性能有显著影响，当使用模量Ms = 1.0的激活剂，每100 g SOFE添加20 g NaO时，抗压强度最佳（35.8 MPa）。本研究体现了AAM生产的可持续方法，并表明废玻璃是用于农业食品工业废过滤土单组分活化的硅酸钠合成的有价值原材料，符合循环经济原则和可持续发展目标。
