赤泥地聚物水泥力学性能和聚合机理

Mechanical Property and Polymerization Mechanism of Red Mud Geopolymer Cement

以活化赤泥和矿渣为主要原料制备了赤泥地聚物水泥(RMPC),研究了矿渣掺量、激发剂(水玻璃)模数及其掺量对RMPC力学性能和聚合机理的影响.结果表明:矿渣显著改善了RMPC砂浆的力学性能,其掺量为40%时,RMPC砂浆的抗压强度最高;水玻璃模数为1.5或1.2时,RMPC砂浆的抗压强度和抗折强度最佳;当水玻璃模数为1.5时,RMPC砂浆的抗压强度随水玻璃掺量增大而增大,且水玻璃掺量为20%时,RMPC抗折强度最高;赤泥和矿渣中的活性硅、铝组分在水玻璃作用下,参与地质聚合反应和水化硬化过程,生成以类沸石地聚物和水化硅(铝)酸钙(C-(A)-S-H)凝胶为骨架的地聚物结构.

Activated red mud and slag were used as the main raw material to prepare red mud geopolymer cement(RMPC).The effects of slag dosage,activator(sodium silicate)modulus and its dosage on mechanical properties and polymerization mechanism of RMPC were studied.The results show that slag can significantly improve the mechanical properties of RMPC mortar.When the dosage of slag is 40%,the compressive strength of RMPC mortar is on the highest.When the modulus of sodium silicate is 1.5 or 1.2,the compressive strength and flexural strength of RMPC mortar are on the best.When the modulus of sodium silicate is 1.5,the compressive strength of RMPC mortar increases with the increase of the dosage of sodium silicate,and the flexural strength is on the highest when the dosage of sodium silicate is 20%.The active silicon and aluminum components in red mud and slag participate in the geological polymerization reaction and hydration hardening process under the action of sodium silicate,and form the geopolymer structure with the framework of zeolite geopolymer and C-(A)-S-H gel.