基于逆Leidenfrost效应的多孔地聚合物微球孔结构及pH缓冲性能

Pore Structure and pH Buffering Performance of Porous Geopolymer Microspheres Based on Inverse Leidenfrost Effect

以水玻璃、矿渣粉为材料,基于逆Leidenfrost效应制备了多孔地聚合物微球,研究了其孔结构及pH缓冲性能.结果表明:改变水玻璃掺量和水固比可以调控多孔地聚合物微球的孔结构和pH缓冲性能;当水固比为1.0、水玻璃掺量由4%增大至8%时,微球的孔隙率、中位孔径和孔比表面积均减小,pH值波动范围为1.50~1.90;当水玻璃掺量为4%、水固比由1.0增大至1.2时,微球的孔隙率、中位孔径和孔比表面积均增大,pH值波动范围超过2.00;与双氧水直接发气法制备的多孔地聚合物相比,基于逆Leidenfrost效应制备的多孔地聚合物具有更好的pH缓冲性能和更高的OH-累积浸出量.

Porous geopolymer microspheres were prepared using water glass and slag as raw materials based on inverse Leidenfrost effect.The results reveal that the pore structure and pH buffering performance of the porous geopolymer microspheres can be adjusted by varying the water glass content and the water-solid ratio.When the water-solid ratio is 1.0 and the water glass content is raised from 4%to 8%,a decrease in the median pore radius,porosity,and pore specific surface area of microspheres is observed,and pH fluctuation is in the range of 1.50-1.90.When the water glass content is 4%and the water-solid ratio increases from 1.0 to 1.2,the median pore radius,porosity,and pore specific surface area of microspheres increase,and pH fluctuation exceeds 2.00.Notably,the inverse Leidenfrost effect results in the preparation of porous geopolymers with superior pH buffering performance and higher cumulative leaching amount of OH-compared to those generated via direct gassing with hydrogen peroxide.