0

Scoping Candidate Minerals for Stabilization of Arsenic-Bearing Solid Residuals

Madhumitha Raghav, Jilei Shan, A Eduardo Sáez, Wendell P Ela

J Hazard Mater. 2013 Dec 15;263 Pt 2(0 2):525-32.

PMID: 24231323

Abstract:

Arsenic Crystallization Technology (ACT) is a potentially eco-friendly, effective technology for stabilization of arsenic-bearing solid residuals (ABSRs). The strategy is to convert ABSRs generated by water treatment facilities into minerals with a high arsenic capacity and long-term stability in mature, municipal solid waste landfills. Candidate minerals considered in this study include scorodite, arsenate hydroxyapatites, ferrous arsenates (symplesite-type minerals), tooeleite, and arsenated-schwertmannite. These minerals were evaluated as to ease of synthesis, applicability to use of iron-based ABSRs as a starting material, and arsenic leachability. The Toxicity Characteristic Leaching Procedure (TCLP) was used for preliminary assessment of candidate mineral leaching. Minerals that passed the TCLP and whose synthesis route was promising were subjected to a more aggressive leaching test using a simulated landfill leachate (SLL) solution. Scorodite and arsenate hydroxyapatites were not considered further because their synthesis conditions were not found to be favorable for general application. Tooeleite and silica-amended tooeleite showed high TCLP arsenic leaching and were also not investigated further. The synthesis process and leaching of ferrous arsenate and arsenated-schwertmannite were promising and of these, arsenated-schwertmannite was most stable during SLL testing. The latter two candidate minerals warrant synthesis optimization and more extensive testing.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
AS2121219 TCLP Metals CA-WET in Soil TCLP Metals CA-WET in Soil Price
qrcode