Effect of heavy metals and water content on the strength of magnesium phosphate cements

被引：167

作者：

Buj, Irene ^{[1
]}

Torras, Josep ^{[2
]}

Casellas, Daniel ^{[2
]}

Rovira, Miquel ^{[2
]}

de Pablo, Joan ^{[2
]}

机构：

[1] Tech Univ Catalonia, Dept Mech Engn, Barcelona 08028, Spain

[2] Tech Univ Catalonia, CTM Technol Ctr, Barcelona 08028, Spain

来源：

JOURNAL OF HAZARDOUS MATERIALS | 2009年 / 170卷 / 01期

关键词：

Magnesium phosphate cements; Compressive strength; Tensile strength; Bobierrite; Hazardous wastes; RAPID REPAIR; CONCRETE; AMMONIUM; MORTAR; PH;

D O I：

10.1016/j.jhazmat.2009.04.091

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

In this paper the mechanical properties of magnesium potassium phosphate cements used for the Stabilization/Solidification (S/S) of galvanic wastes were investigated. Surrogate wastes (metal nitrate dissolutions) were employed containing Cd, Cr(III), Cu, Ni, Pb or Zn at a concentration of 25 g dm(-3) and different water-to-solid (W/S) ratios (0.3, 0.4, 0.5 and 0.6 dm(3) kg(-1)) have been employed. Cements were prepared by mixing hard burned magnesia of about 70% purity with potassium dihydrogen phosphate. Compressive strength and tensile strength of specimens were determined. In addition the volume of permeable voids was measured. It was found that when comparing pastes that the volume of permeable voids increases and mechanical strength decreases with the increase of water-to-solid ratio (W/S). Nevertheless pastes with the same material proportions containing different metals show different mechanical strength values. The hydration products were analyzed by XRD. With the increase of water content not previously reported hydration compound was detected: bobierrite. (C) 2009 Elsevier B.V. All rights reserved.

引用

页码：345 / 350

页数：6