Linked Life Data

14719252

Source:http://linkedlifedata.com/resource/pubmed/id/14719252

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2004-1-14
pubmed:abstractText
Twenty-six natural clays were studied for their kinetics of flocculating and removing algal cells of Microcystis aeruginosa. According to the 8 h equilibrium removal efficiencies and removal rates at a clay-loading of 0.7 g.L-1, all the 26 clays were classified into three categories. Type-I clay, which includes talc, ferric oxide, sepiolite, ferroferric oxide, and kaolinite, has an equilibrium removal efficiency greater than 90%, a t50 (time needed to remove 50% of the algae) of less than 30 min, and a t80 (time needed to remove 80% of the algae) of less than 2.5 h. Type-II clay, which includes argillanceous rocks, attapulgite, rectorite, illite, and argil, etc., has an equilibrium removal efficiency of 50%-80%, a t50 of less than 2.5 h, and a t80 of more than 5 h. Type-III clay consists of 14 minerals, including laterite, zeolite, mica, clinoptilolite, pumice, tripoli, feldspar and quartz, etc. with the removal efficiency less than 50%, and t50 > > 8 h. When the clay loading was decreased to 0.1-0.2 g.L-1, the 8 h equilibrium removal efficiencies for 25 clays declined to below 60%, except for sepiolite, a Type-I clay, which maintained around 90%. After the sepiolite was modified with Fe3+ to increase its surface charge (Zeta potential from -24.0 mV to +0.43 mV at pH 7.4), the initial removal rate was increased remarkably although its 8 h equilibrium removal efficiency was not improved substantially. As a comparison, the 8 h equilibrium removal efficiency of PAC was no greater than 40% at loadings of 0.02-0.2 g.L-1. Following the analysis of the flocculation mechanism it was concluded that the effect of bridging and netting may play a key role in the clay-algae flocculation processes, which may be important for selecting and modifying clays to improve significantly the removal efficiency.
pubmed:language
chi
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0250-3301
pubmed:author
pubmed:issnType
Print
pubmed:volume
24
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-10
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
[Kinetics and mechanism of removing Microcystis aeruginosa using clay flocculation].
pubmed:affiliation
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. gpan@mail.rcees.ac.cn
pubmed:publicationType
Journal Article, English Abstract, Research Support, Non-U.S. Gov't