(1. 南京工业大学 安全科学与工程学院,南京211816;
2. 中南大学 化学化工学院,长沙410083;
3. 中南大学 锰资源高效清洁利用湖南省重点实验室,长沙 410083)
摘 要: 基于电解锰渣成分及水化硅酸钙(C-S-H)材料的结构特性,提出以电解锰渣为原料制备C-S-H材料,开发电解锰渣基C-S-H材料制备新技术。系统研究由电解锰渣制备C-S-H材料过程中反应pH值、反应温度、晶化时间等因素对合成C-S-H材料的矿相、微观结构和溶钙性能的影响。结果表明:C-S-H产品的种类、微观结构及其溶钙性能与反应工艺条件紧密相关,在优化工艺条件下(反应pH值12.0、反应温度100 ℃、晶化时间10 h)制备所得的C-S-H材料结构酥松,其比表面积为205.0 m2/g,总孔孔容为0.68 cm3/g,且溶钙能力最强,溶出钙离子浓度为11.52 mg/L,适合作为吸附除磷材料在水处理过程中使用。
关键字: 电解锰渣;水化硅酸钙;合成条件;微观结构;溶钙性能
(1. College of safety Science and Engineering, Nanjing Technology University, Nanjing 211816, China;
2. College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China;
3. Hunan Provincial Key Laboratory of Efficient and Clean Utilization of Manganese Resources, Central South University, Changsha 410083, China)
Abstract:Based on the composition of electrolytic manganese residue (EMR) and the structural characteristics of hydrated calcium silicate (C-S-H) material, a novel technology was used for EMR based C-S-H material preparation using EMR as raw material. Calcium silicate hydrate (C-S-H) was synthesized from electrolytic manganese residue (EMR) via a hydrothermal synthetic procedure. The major factors influencing the crystalline phase, microstructure and Ca2+ release capacity of C-S-H were investigated in the aspects of reaction pH value, reaction temperature and crystallization time. The results show that the crystalline phase, microstructure and Ca2+ release capacity of C-S-H are greatly affected by the reaction pH value, reaction temperature and crystallization time during the preparation process. And the optimal condition for C-S-H synthesized from electrolytic manganese residue is determined to reaction pH value of 12.0, reaction temperature of 100 ℃ and crystallization time of 10 h. And the product synthesized under the optimal condition is identified to be a calcium silicate hydrate with a specific surface area and pore volume of 205 m2/g and 0.68 cm3/g, respectively. Meanwhile, under the above conditions, Ca2+ release capacity is 11.52 mg/L, making this material a promising candidate for removal of phosphate ions diluted in wastewater.
Key words: electrolytic manganese residue; calcium silicate hydrate; synthesis condition; microstructure; Ca2+ release capacity