Identity and yields of major halogenated products of aquatic fulvic acid chlorination

Christman, Russell F.; Norwood, Daniel L.; Millington, Douglas; Johnson, J. Donald; Stevens, Alan A.

doi:10.1021/es00116a012

Cited by 268 publications

(126 citation statements)

References 7 publications

Supporting

Mentioning

113

Contrasting

Unclassified

Order By: Relevance

“…The effect of MW on HAA precursor removal by the coagulation process was not significant. The ability of AlCl 3 and PACl of removing HAA precursors did not have significant differences.…”

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 76%

“…Aromatic carboxylates were adsorbed predominantly on aluminum hydroxide (26). In this study, the negatively charged flocs of Al(OH) 3 or Al(OH)4 -ions (Hundt and O'Melia indicated that the Al(OH) 3(s) precipitate decreased along with an increase of pH; this is attributed to the presence of Al(OH) 4 -at high pH values (6)) were not effective on aliphatic structure removal through adsorption at pH 9.5, particularly when the MW was low. Because of residual K-Al 13, PACl removed more THM precursors than AlCl 3 by adsorption.…”

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 76%

“…Thus, the ability of AlCl 3 and PACl for removal of HAA precursors did not have significant differences. Besides, high MW HAA precursors precipitated more easily through self-aggregation than low MW ones.…”

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 83%

“…In particular, humic substances are the principal precursors of trihalomethanes (THMs) (2) and haloacetic acids (HAAs) (3).…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Role of Aluminum Speciation in the Removal of Disinfection Byproduct Precursors by a Coagulation Process

Zhao

Liu

et al. 2008

Environ. Sci. Technol.

124

View full text Add to dashboard Cite

Humic acid (HA) was extracted and separated into different molecular weight (MW) fractions, then coagulated by aluminum chloride and polyaluminum chloride (PACl). The removal of disinfection byproduct (DBP) precursors and the aluminum speciation variation of the coagulants were investigated in detail. In particular, the role of aluminum speciation in the removal of DBP precursors was discussed. During the coagulation process, AlCl 3 hydrolyzed into dominating in situ Al 13 species at pH 5.5. The in situ Al 13 species exhibited better removal ability for haloacetic acid (HAA) precursors than PACl. At pH 7.5, in situ hydrolyzed Al 13 species of AlCl 3 decomposed into dimeric Al species. In this case, preformed Al 13 of PACl had a high removal ability of HAA precursors. Specially, the greatest reduction of HAA precursors with a low MW (<30 kDa) was through charge neutralization at pH 5.5, and that of HAA precursors in high MW (>30 kDa) fractions was through adsorption at pH 7.5. Different from HAA precursors, the in situ Al 13 species did not have a high removal ability of trihalomethane (THM) precursors. Therefore, PACl exhibited a better removal ability of THM precursors than AlCl 3 at different pH values. In the different MW fractions, the greatest reduction of THM precursors was through charge neutralization at pH 5.5.

show abstract

“…The effect of MW on HAA precursor removal by the coagulation process was not significant. The ability of AlCl 3 and PACl of removing HAA precursors did not have significant differences.…”

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 76%

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 76%

Section: Role Of Aluminum Speciation In Removal Of Dbp Precursors Witmentioning

confidence: 83%

“…In particular, humic substances are the principal precursors of trihalomethanes (THMs) (2) and haloacetic acids (HAAs) (3).…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Role of Aluminum Speciation in the Removal of Disinfection Byproduct Precursors by a Coagulation Process

Zhao

Liu

et al. 2008

Environ. Sci. Technol.

124

View full text Add to dashboard Cite

show abstract

“…The disinfectants react with NOM in the water to produce a host of DBPs, many of which are halogenated compounds suspected of having adverse human health effects. Trihalomethanes (THMs) and haloacetic acids (HAAs) are the principal DBPs formed from chlorination of water [1][2][3]. Although THMs have been regulated in the US since 1979, the US Environmental Protection Agency (USEPA) recently promulgated Stage 1 of its Disinfectants and Disinfection ByProducts (D/DBP) Rule establishing maximum contaminant levels (MCLs) for THMs and HAAs.…”

Section: Introductionmentioning

confidence: 99%

Enhanced coagulation using a magnetic ion exchange resin

2002

View full text Add to dashboard Cite

The objective of this investigation was to examine the effectiveness of a magnetic ion exchange resin (MIEX s ) to enhance the coagulation of disinfection by-product precursors in nine surface waters, each representing a different element of the USEPA's 3 Â 3 enhanced coagulation matrix. The effect of MIEX-pretreatment on the requisite alum dose needed for subsequent coagulation of turbidity was also evaluated.Enhanced coagulation with MIEX was found to be very effective for removing trihalomethane (THM) and haloacetic acid (HAA) precursors from the nine waters examined. THM and HAA formation potential was reduced by more than 60% in all of the waters studied; reductions approaching 90% were seen in the waters with the highest specific ultraviolet absorbance values. The residual total organic carbon concentration, ultraviolet absorbance, and THM and HAA formation potential were all substantially lower as a result of MIEX and alum treatment compared to alum coagulation alone. MIEX pre-treatment also lowered the coagulant demand of each of the waters substantially. r

show abstract

Trends in levels of disinfection by-products

Benoit

LeBel

1998

Environmetrics

View full text Add to dashboard Cite

Identity and yields of major halogenated products of aquatic fulvic acid chlorination

Cited by 268 publications

References 7 publications

Role of Aluminum Speciation in the Removal of Disinfection Byproduct Precursors by a Coagulation Process

Role of Aluminum Speciation in the Removal of Disinfection Byproduct Precursors by a Coagulation Process

Enhanced coagulation using a magnetic ion exchange resin

Trends in levels of disinfection by-products

Contact Info

Product

Resources

About