In this work, comprehensive utilization of phosphogypsum was developed. Methylene blue (MB) in aqueous solution was adsorbed by waste phosphogypsum (PG), and then the MB-adsorbed PG was used to the fabrication of PG bricks. The adsorption mechanism and the strength of PG bricks also have been studied. The dye maximum capacity of PG monolayer adsorption was found to be 0.2mg/g. The kinetic behavior is more accordant with the intra-particle diffusion equation. The MB-adsorbed PG could be effectively used as a raw material for building material. The mechanical properties of PG bricks were little different from the one of the water-washed PG bricks. The 2h-flexural and compressing strengths were about 2.8MPa and 6MPa, the dry-flexural and compressing strengths were about 5MPa and 20MPa.

中文翻译：

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磷石膏的综合利用：亚甲基蓝的吸附及其在砖中的应用

本工作开展了磷石膏的综合利用工作。用废磷石膏（PG）吸附水溶液中的亚甲蓝（MB），然后将MB吸附的PG用于制备PG砖。对PG砖的吸附机理和强度也进行了研究。发现 PG 单层吸附的染料最大容量为 0.2毫克/克。动力学行为更符合粒子内扩散方程。MB吸附的PG可以有效地用作建筑材料的原料。PG 砖的力学性能与水洗 PG 砖中的一种几乎没有区别。2h 抗弯和抗压强度约为 2.8兆帕和6MPa，干抗弯和抗压强度约为5兆帕和20兆帕。