Hazardous industrial waste stabilization using inorganic phosphates: Investigation of possible mechanisms
The present study focuses on the use of phosphate-containing compounds, such as apatites, as stabilization additives for solid industrial wastes. The examined highly toxic waste contained mainly lead, iron, and bromides. Phosphates (synthetic or natural), when used as additives, were found to diminish the release of lead from the stabilized waste below the respective legislative concentration limits, following the application of DIN 38414 standard leaching method and within the range of pH values 7.5–10.5. The respective synthetic compounds of lead, PbO and Pb(OH)Br, existing also in the solid waste, were additionally studied during simulation experiments, in order to examine the possible mechanisms of waste stabilization, by using the same additives (phosphates). The obtained results showed the possibility of another parallel mechanism, different from that proposed in the literature, which is the sorption of aqueous lead ions onto the apatite surface. It was suggested that lead can be also transformed into the less soluble solid phases through the interaction (surface crystallization) of exposed lead surface with the aqueous environment. The formation of new crystals onto the surface of lead phase was sufficiently fast, especially in the case of natural phosphate mineral additive, most probably due to the presence of calcite, which supplies part of its carbonate content for the formation of respective lead carbonate solid phases
Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης, Σχολή Θετικών Επιστημών, Τμήμα Χημείας
Pure and Applied Chemistry, vol.77 no.10  p.1737-1752 [Published Version]
This record is part of 'IKEE', the Institutional Repository of Aristotle University of Thessaloniki's Library and Information Centre found at http://ikee.lib.auth.gr. Unless otherwise stated above, the record metadata were created by and belong to Aristotle University of Thessaloniki Library, Greece and are made available to the public under Creative Commons Attribution-ShareAlike 4.0 International license (http://creativecommons.org/licenses/by-sa/4.0).
Unless otherwise stated in the record, the content and copyright of files and fulltext documents belong to their respective authors. Out-of-copyright content that was digitized, converted, processed, modified, etc by AUTh Library, is made available to the public under Creative Commons Attribution-ShareAlike 4.0 International license (http://creativecommons.org/licenses/by-sa/4.0). You are kindly requested to make a reference to AUTh Library and the URL of the record containing the resource whenever you make use of this material.
*Institutions are responsible for keeping their URLs functional (digital file, item page in repository site)