EPA Science Inventory

Crystal and Morphological Phase Transformation of Pb(II) to Pb(IV) in Chlorinated Water

Citation:

LYTLE, D. A., C. WHITE, M. N. NADAGOUDA, AND A. WORRALL. Crystal and Morphological Phase Transformation of Pb(II) to Pb(IV) in Chlorinated Water. JOURNAL OF HAZARDOUS MATERIALS. Elsevier Science Ltd, New York, NY, 165(1-3):1234-1238, (2009).

Description:

Herein, we show that an important transformation of Pb(II) to Pb(IV) under laboratory conditions which is intended to represent in real water flowing system in lead pipes. These results will give an insight in understanding the scale formation in lead pipes and dissolution of lead. The experiments were conducted to elucidate the morphology of lead (IV) oxide mineral transformation from hydrocerussite and its relationship to color change observed after extended periods of aging. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to understand the surface morphology, shape and sizes. The X-ray diffraction (XRD) studies were conducted to establish the crystal structure. The SEM, TEM and XRD results were compared over the period of time (14 days aging) to observe correlations between the crystal structure transformation and morphology. XRD results showed that on after precipitation of the experiment hydrocerussite dominated and after aging to cerussite (PbCO3) and á-PbO2 and ß-PbO2. Lead precipitates i.e hydrocerussite changed color from white to reddish brown confirming a transformation of the lead phase and oxidation state with time. This was correlated to a change in morphology from flower shaped crystals to hexagonal bars and small cubic to spherical structures.

Purpose/Objective:

CWA

URLs/Downloads:

CRYSTAL AND MORPHOLOGICAL PHASE TRANSFORMATION OF PB(II) TO PB(IV) IN CHLORINATED WATER   Exit

Record Details:

Record Type: DOCUMENT (JOURNAL/PEER REVIEWED JOURNAL)
Start Date: 09/15/2009
Completion Date: 09/15/2009
Record Last Revised: 05/07/2009
Record Created: 03/24/2008
Record Released: 03/24/2008
OMB Category: Other
Record ID: 189671

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL RISK MANAGEMENT RESEARCH LABORATORY

WATER SUPPLY AND WATER RESOURCES DIVISION

TREATMENT TECHNOLOGY EVALUATION BRANCH