An immobilisation mechanism for lead in fly ash subjected to mechanochemical treatment Online publication date: Sat, 20-Sep-2014
by Nomura Yugo; Fujiwara Kazuo; Akihiko Terada; Nakai Satoshi; Hosomi Masaaki
International Journal of Environment and Waste Management (IJEWM), Vol. 12, No. 3, 2013
Abstract: Mechanochemical (MC) processes immobilise heavy metals in fly ash, a desirable outcome because recycled fly ash is commonly used in the synthesis of inorganic materials. We investigate the extent of immobilisation and the mechanism of lead (Pb) leaching during MC treatment of fly ash, using lead oxide (PbO) and lead dichloride (PbCl2) as model compounds. MC treatment of the fly ash inhibited Pb leaching by about 97% after a 12 h treatment. PbO was reduced to elemental Pb in a redox reaction by abraded iron (Fe) produced from the stainless steel ball mill used for MC treatment, and a phase transition of the PbO crystal structure from orthorhombic to tetragonal was confirmed. Production of Pb species with sparing solubility in water resulted in immobilisation of the Pb within the fly ash. Other insoluble intermediates detected in the milled samples, such as Pb2O3, potentially contribute to the inhibition of Pb leaching.
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Environment and Waste Management (IJEWM):
Login with your Inderscience username and password:
Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.
If you still need assistance, please email subs@inderscience.com
Our Blog 
Follow us on Twitter 
Visit us on Facebook