摘要
为研究炉渣在地聚合物中应用,将磨细炉渣和偏高岭土按1∶1的质量比混合后作为地聚合物原材料,以水玻璃、氢氧化钠为激发剂制备地聚合物材料,研究了碱当量、激发剂模数和养护条件对炉渣基地聚合物抗压强度的影响,并利用XRD、SEM分析地聚合物的微观结构。结果表明:随着激发剂模数和碱当量的增大,炉渣基地聚合物的抗压强度呈先提高后降低的趋势;高温养护有利于地聚合物抗压强度的提高,养护温度过高则会导致抗压强度下降,且适当延长养护时间会大大提高地聚合物的抗压强度。微观分析表明,炉渣基地聚合反应产物为絮状凝胶物质,呈非晶态或半晶态,且炉渣参与了地聚合反应。
To research the utilization of bottom ash,geopolymers were synthetized from bottom ash and metakaolin with equal proportion,using sodium hydroxide(NaOH) and sodium silicate(Na_2SiO_3)solutions as activators. The influence of silica modulus,activator dosage and cure conditions on the compressive strength of bottom ash-metakaolin based geopolymers were explored. The microstructure was characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM). The results show that with the increase of silica modulus and activator dosage,the compressive strength of geopolymers increases first and then decreases. High temperature curing is beneficial for the development of compressive strength,but if too high,it will lead to a decrease. Prolonged curing time will greatly promote the compressive strength of the geopolymer. Microscopic analysis indicates that the bottom ash participates in geopolymerization and the geopolymer material is composed of amorphous phase and semi-crystalline phase.
引文
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