Linked Life Data

19921902

Source:http://linkedlifedata.com/resource/pubmed/id/19921902

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
2009-11-20
pubmed:abstractText
Natural organic matter (NOM) removal during water softening is thought to occur through adsorption onto or coprecipitation with calcium and magnesium solids. However, details of precipitate composition and surface chemistry and subsequent interactions with NOM are relatively unknown. In this study, zeta potentiometry analyses of precipitates formed from inorganic solutions under varying conditions (e.g., Ca-only, Mg-only, Ca + Mg, increasing lime or NaOH dose) indicated that both CaCO3 and Mg(OH)2 were positively charged at higher lime (Ca(OH)2) and NaOH doses (associated with pH values above 11.5), potentially yielding a greater affinity for adsorbing negatively charged organic molecules. Environmental scanning electron microscopy (ESEM) images of CaCO3 solids illustrated the rhombohedral shape characteristic of calcite. In the presence of increasing concentrations of magnesium, the CaCO3 rhombs shifted to more elongated crystals. The CaCO3 solids also exhibited increasingly positive surface charge from Mg incorporation into the crystal lattice, potentially creating more favorable conditions for adsorption of organic matter. NOM adsorption experiments using humic substances extracted from Lake Austin and Missouri River water elucidated the role of surface charge and surface area on adsorption.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0013-936X
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
7837-42
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Effect of softening precipitate composition and surface characteristics on natural organic matter adsorption.
pubmed:affiliation
The University of Texas at Austin, Department of Civil, Architectural, and Environmental Engineering, Austin, Texas 78712, USA. crussell@pirnie.com
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't