Fig. 1
From: Investigation of Cd(II) sorption by mackinawite (FeS) under anoxic conditions
Dissolved Cd(II) concentration ([Cd(II)]diss) as a function of initial Cd(II) concentration ([Cd(II)]0) in 2 g/L FeS batches (a) and dissolved Fe(II) concentration ([Fe(II)]diss) as a function of [Cd(II)]0 in 10 g/L FeS batches (b). In part a, the dashed line represents the maximum contamination level (MCL, 5 ppb) according to U.S. EPA. In part b, the solid line represents the solubility of FeS, which was directly measured from FeS batches in the absence of Cd(II)