scholarly journals The roles of bromide and precursor structures on DBP formation and species distribution

2006 ◽  
Vol 6 (4) ◽  
pp. 27-33 ◽  
Author(s):  
G.S. Wang ◽  
P.L. Huang
Keyword(s):  
Organic Matter ◽  
Organic Acids ◽  
Natural Organic Matter ◽  
Species Distribution ◽  
Ph Effect ◽  
Free Chlorine ◽  
Haloacetic Acids ◽  
Formation Potential ◽  
Trihalomethane Formation Potential

This study investigates the role of bromide and the structure of precursors in DBPs formation. Resorcinol (1,3-dihydroxylbenzene) and 2,4-pentadiol were used to represent the aromatic and aliphatic precursors. Laboratory prepared hydrophilic organic acids was used to simulate the mixtures of the aqueous natural organic matter. The results showed that about 60% of the bromide was transformed into HOBr and OBr− by chlorine when the chlorine dosages was high (5–20 mg/L of free chlorine). However, only 20% of bromide was transformed into HOBr and OBr− at low chlorine dosage (1 mg/L). Trihalomethane formation potential (THMFP) measurements showed that higher THMs formation was obtained at higher pH for 2,4-pentadiol, mainly due to the presence of the bromo-THMs. For resorcinol, however, no bromo-THMs are formed at either pH 7 or 9. For THMFP from hydrophilic organic acids, no apparent pH effect was observed. It is concluded that the higher THM formation at higher pH was mainly due to the formation of bromo-THMs from the aliphatic precursors. Similar trends are obtained in THMFP measurements for haloacetic acids formation potential (HAAFP).

Using HPSEC to identify NOM fraction removal and the correlation with disinfection by-product precursors

2015 ◽  
Vol 16 (2) ◽  
pp. 305-313 ◽  
Author(s):  
Euis Nurul Hidayah ◽  
Yung-Chen Chou ◽  
Hsuan-Hsien Yeh
Keyword(s):  
Humic Substances ◽  
Natural Organic Matter ◽  
High Performance ◽  
Haloacetic Acids ◽  
Size Exclusion ◽  
Formation Potential ◽  
Trihalomethane Formation Potential ◽  
Exclusion Chromatography ◽  
Alum Coagulation ◽  
Aliphatic Biopolymer

In this study high performance size exclusion chromatography (HPSEC) was used to compare an ultrafiltration (UF) membrane and alum coagulation for their capacity to remove different fractions of natural organic matter (NOM) from water. At the same time, the removal of disinfection by-product (DBP) precursors, as measured by trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP), was also detected. The results show that the UF membrane mainly removed the aliphatic biopolymer fraction, while alum coagulation mainly removed the humic substances fraction. The results of DBP precursor analysis show that more THMFP was removed by the UF membrane than HAAFP, while the reverse was true for alum coagulation. It is conjectured that the aliphatic biopolymer fraction is the major precursor for trihalomethanes (THMs), while the humic substances fraction is the major precursor for haloacetic acids (HAAs).

Ozonation of natural organic matter and aquatic humic substances: the effects of ozone on the structural characteristics and subsequent trihalomethane formation potential

2020 ◽  
Vol 55 (2) ◽  
pp. 155-166
Author(s):  
Mehrnaz Sadrnourmohammadi ◽  
Kenneth Brezinski ◽  
Beata Gorczyca
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Structural Characteristics ◽  
Aromatic Rings ◽  
Formation Potential ◽  
Trihalomethane Formation Potential ◽  
Vis Spectroscopy ◽  
Reflectance Ftir ◽  
Main Components ◽  
Humic Fractions

Abstract The effect of ozonation on the structural and chemical characteristics of natural organic matter (NOM) and its isolated humic fractions, humic acid (HA) and fulvic acid, were studied using Fourier transform infrared coupled to attenuated total reflectance (FTIR-ATR), ultraviolet/visible (UV/Vis) spectroscopy, and synchronous scanning fluorescence (SSF) spectroscopy. The results were linked to the effect of ozonation on trihalomethane formation potential (THMfp) reduction for water standards with high THM precursors. Results showed that ozonation at a dose of 1 mg ozone/mg dissolved organic carbon (DOC) was capable of reducing DOC, UV absorbance at 254 nm (UV254), and THMfp by up to 42%, 95%, and 89% for the HA water standard, respectively. The study of UV/Vis, FTIR-ATR, and SSF revealed trends showing that ozone can alter the composition of DOC in the water standards, causing a significant reduction in aromaticity. The reduction of UV254 for each ozonated sample also affirms that ozone mainly targets aromatic moieties contained in NOM. FTIR-ATR results showed that the reduction of unsaturated functional groups, including aromatic rings and C = C bonds in the water standards tested, were the main components impacted by ozone application. SSF results also revealed that ozonation decreases the fluorescence intensity of the maximum peak – as well as the whole spectra.

Photocatalytic oxidation of natural organic matter surrogates and the impact on trihalomethane formation potential

Chemosphere ◽  
2010 ◽  
Vol 81 (11) ◽  
pp. 1509-1516 ◽  
Author(s):  
Karine K. Philippe ◽  
Claudia Hans ◽  
Jitka MacAdam ◽  
Bruce Jefferson ◽  
Julie Hart ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Photocatalytic Oxidation ◽  
Formation Potential ◽  
Trihalomethane Formation Potential ◽  
The Impact

Removal of natural organic matter and trihalomethane formation potential in a full-scale drinking water treatment plant

2013 ◽  
Vol 13 (4) ◽  
pp. 1099-1108 ◽  
Author(s):  
Ekaterina Vasyukova ◽  
René Proft ◽  
Johanna Jousten ◽  
Irene Slavik ◽  
Wolfgang Uhl
Keyword(s):  
Molecular Weight ◽  
Organic Matter ◽  
Organic Carbon ◽  
Natural Organic Matter ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Full Scale ◽  
Formation Potential ◽  
Trihalomethane Formation Potential

A multidisciplinary approach was applied in this work to characterise natural organic matter and evaluate the performance of a full-scale waterworks treating organic-rich surface water. It was shown that the combination of the treatment processes considered efficiently removed the dissolved organic matter, including its specific fractions. Most of the dissolved organic carbon and nitrogen (DOC and DON), biodegradable DOC and DON, as well as assimilable organic carbon were removed by coagulation/sedimentation. However, the coagulation process was not likely to be optimised for the removal of all molecular weight compounds. The breakdown of high molecular weight compounds into others of low molecular weight, as well as the production of biodegradable organic matter during ozonation, proved to enhance their removal efficiency by subsequent biological activated carbon filtration. The specific trihalomethane formation potential decreased during treatment, indicating a decrease in reactivity of DOC with chlorine across the treatment train. Fractionation experiments demonstrated that high and medium molecular weight organics were likely to be the main precursors for the formation of trihalomethanes. However, other disinfection by-products (such as haloacetic acids) should also be controlled, as the chlorine demand pattern did not necessarily follow that of trihalomethane formation.

The effects of ultraviolet/H2O2 advanced oxidation on the content and characteristics of groundwater natural organic matter

2014 ◽  
Vol 15 (1) ◽  
pp. 34-41 ◽  
Author(s):  
J. Molnar ◽  
J. Agbaba ◽  
A. Tubić ◽  
M. Watson ◽  
M. Kragulj ◽  
...  
Keyword(s):  
Organic Matter ◽  
Natural Organic Matter ◽  
Advanced Oxidation ◽  
Total Content ◽  
Process Conditions ◽  
Water Type ◽  
H2o2 Treatment ◽  
Trihalomethane Formation Potential ◽  
Aromatic Character ◽  
A Minor

This work investigates the effects of ultraviolet (UV)/H2O2 advanced oxidation on the content and characteristics of natural organic matter (NOM) originating from two different groundwaters (3.03–9.69 mg/L total organic carbon (TOC), 2.71–4.31 Lmg−1m−1 specific ultraviolet absorbance (SUVA)). Application of UV irradiation resulted in a minor reduction in the total content of NOM. Using UV/H2O2 advanced oxidation led to a significant reduction of the aromatic character of NOM (SUVA was reduced by up to 80%) and an increase in the hydrophilic character of the residual NOM, with the optimal UV/H2O2 treatment conditions depending on the water type. In addition, fluctuations in trihalomethane formation potential (THMFP) were observed depending on the UV/H2O2 process conditions, with a maximal reduction of about 40% achieved for both waters.

Control of disinfection and halogenated disinfection byproducts by the electrochemical process

2007 ◽  
Vol 55 (12) ◽  
pp. 213-219 ◽  
Author(s):  
Y.J. Jung ◽  
B.S. Oh ◽  
J.W. Kang ◽  
M.A. Page ◽  
M.J. Phillips ◽  
...  
Keyword(s):  
Kinetic Studies ◽  
Disinfection Byproducts ◽  
Electrochemical Process ◽  
Free Chlorine ◽  
Haloacetic Acids ◽  
Oh Radicals ◽  
Inactivation Kinetic ◽  
E Coli ◽  
Electrochemical Processes

The aim of this study was to investigate some aspects of the performance of electrochemical process as an alternative disinfection strategy, while minimising DBPs, for water purification. The study of electrochemical processes has shown free chlorine to be produced, but smaller amounts of stronger oxidants, such as ozone, hydrogen peroxide and OH radicals (•OH), were also generated. The formation of mixed oxidants increased with increasing electric conductivity, but was limited at conductivities greater than 0.6 mS/cm. Using several microorganisms, such as E. coli and MS2 bacteriophage, inactivation kinetic studies were performed. With the exception of free chlorine, the role of mixed oxidants, especially OH radicals, was investigated for enhancement of the inactivation rate. Additionally, the formation and reduction of DBPs was studied by monitoring the concentration of haloacetic acids (HAAs) during the process.

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