Characterisation of natural organic matter from the Nordic typing project water samples by chemometric analysis of their near infrared spectral profiles

2000 ◽  
Vol 50 (2) ◽  
pp. 225-234 ◽  
Author(s):  
Alfred A Christy ◽  
Per K Egeberg
2018 ◽  
Author(s):  
Isabela Carreira Constantino ◽  
Amanda Maria Tadini ◽  
Marcelo Freitas Lima ◽  
Lídia Maria de Almeida Plicas ◽  
Altair Benedito Moreira ◽  
...  

Abstract. Natural organic matter (NOM) is an important component for understanding the behavior of pollutants in the environment. A fraction of NOM is considered labile, fresh and less oxidized. In this work, a simple method was developed to distinguish between labile (LOM) and recalcitrant (ROM) organic matter in freshwater samples. Pyruvate, lignin and fulvic acid were chosen as model compounds of labile and recalcitrant NOM. The samples were submitted to kinetic monitoring experiments using hydrogen peroxide. Pyruvate was the best standard for the quantification of LOM (for concetrations up to 2.9 mg L−1). ROM was quantified by measuring the difference between total organic carbon (TOC) and LOM concentrations. Curves obtained with 0.5 to 5.0 mg L−1 TOC (pyruvate) in freshwater or ultrapure water samples did not indicate the existence of a matrix effect. This simple method was applied to water samples that were collected monthly for one year; the resulting LOM concentrations ranged from 0.47 to 2.1 mg L−1 and the ROM concentrations ranged from 0.08 to 3.5 mg L−1. Based on this results we concluded that hydrogen peroxide kinetics can be used as a simple method to quantify LOM and ROM concentrations in freshwater samples.


2002 ◽  
Vol 36 (9) ◽  
pp. 2357-2371 ◽  
Author(s):  
Patricia A. Maurice ◽  
Michael J. Pullin ◽  
Stephen E. Cabaniss ◽  
Qunhui Zhou ◽  
Ksenija Namjesnik-Dejanovic ◽  
...  

Water SA ◽  
2020 ◽  
Vol 46 (1 January) ◽  
Author(s):  
Welldone Moyo ◽  
Nhamo Chaukura ◽  
Machawe M Motsa ◽  
Titus AM Msagati ◽  
Bhekie B Mamba ◽  
...  

The removal dynamics of biodegradable dissolved organic carbon (BDOC) and natural organic matter (NOM) polarity fractions at a water treatment plant (WTP) in South Africa was studied using UV-Vis absorbance, fluorescence excitation-emission matrix, and two-dimensional synchronous fluorescence spectroscopy (SFS). This study gave insights into the transformation of NOM due to treatment processes. The objectives of the study were: (i) to use chemometric analysis and two-dimensional SFS correlations to investigate the evolution of NOM arising from treatment processes, and (ii) to access the chemical profile dynamics of polarity and BDOC fractions throughout the treatment train. The UV254 absorbance, which indicates aromaticity, reduced by 45%  along the WTP. Gaussian fitting of UV-Vis data showed a decreasing trend in intensity and number of bands along the treatment process. The removal efficiency of NOM components followed the order: humic-like (HL) > tyrosine-like (TYL) > fulvic-like (FL) > tryptophan-like (TPL) > microbial-like (MBL).  At the source, the relative distribution of the hydrophobic (HPO), hydrophilic (HPI), and transphilic (TPI) fractions was 45%, 31%, and 24%, respectively. The HPI was recalcitrant to treatment, and the TYL component of the HPI fraction was conjectured to be a disinfection byproduct limiting reagent. The HL and FL components of the BDOC fraction were the major substrates for bacterial growth. According to two-dimensional-SFS correlation, TYL, TPL, and MBL varied concurrently across the treatment stages. Used for the first time in South Africa, the robustness of a multi-dimensional approach of optical methods coupled with chemometric tools for the assessment of the fate of NOM along the treatment processes was revealed by this study.


2008 ◽  
Vol 8 (6) ◽  
pp. 701-707 ◽  
Author(s):  
S. A. Baghoth ◽  
S. K. Maeng ◽  
S. G. Salinas Rodríguez ◽  
M. Ronteltap ◽  
S. Sharma ◽  
...  

Natural organic matter (NOM) occurs throughout the hydrologic cycle, varying in both amount and character. In this paper, a description of NOM in surface and drinking water, in groundwater and in seawater is presented. Water samples representing these environments were collected and characterized using multiple NOM characterization techniques, including fluorescence excitation emission matrices (F-EEM) and size exclusion liquid chromatography with organic carbon detection (LC-OCD). The results show that the raw surface water as well as the treated water comprises mainly (>70%) of humic substances. The biopolymers, which are more readily biodegradable, contribute up to 2% of the NOM in the raw water but this is completely removed after treatment. For sea water samples, humic substances represent about 50% of the dissolved organic carbon concentration (DOC), while the fraction with size bigger than 20 kDa (biopolymers) represents about 7%. During soil passage, there was preferential removal of non-humic substances (i.e., biopolymers) from wastewater effluent-impacted surface water while the specific ultraviolet absorbance (SUVA), which reflects the aromatic characteristics of organics in a sample, showed an increasing trend along the depth of the soil column. This is a consequence of the removal of non-humic substances (biopolymers) which results in an increase in aromaticity.


2015 ◽  
Author(s):  
Chun-Chieh Yang ◽  
Cristóbal Garrido-Novell ◽  
Dolores Pérez-Marín ◽  
José E. Guerrero-Ginel ◽  
Ana Garrido-Varo ◽  
...  

10.14311/334 ◽  
2002 ◽  
Vol 42 (2) ◽  
Author(s):  
A. Grünwald ◽  
B. Šťastný ◽  
K. Slavíčková ◽  
M. Slavíček

Recent drinking water regulations have lowered the standards for disinfection by-products and have added new disinfection by-products for regulation. Natural organic matter (NOM), mainly humic compounds, plays a major role in the formation of undesirable organic by-products following disinfection of drinking water. Many disinfection by-products have adverse carcinogenic or mutagenic effects on human health. This paper deals with the formation potencial of disinfection by-products in water samples taken from different places in the Flaje catchment.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Kadir Özdemır

This study investigates the fractions of natural organic matter (NOM) and trihalomethane (THM) formation after chlorination in samples of raw water and the outputs from ozonation, coagulation-flocculation, and conventional filtration treatment units. All the water samples are passed through various ultrafiltration (UF) membranes. UF membranes with different molecular size ranges based on apparent molecular weight (AMW), such as 1000, 3000, 10,000, and 30,000 Daltons (Da), are commonly used. The NOM fraction with AMW < 1000 Da (1 K) is the dominant fraction within all the fractionated water samples. Its maximum percentage is 85.86% after the filtration process and the minimum percentage is 65.01% in raw water samples. The total THM (TTHM) yield coefficients range from 22.5 to 42 μg-TTHM/mg-DOC in all fractionated samples, which is related to their specific ultraviolet Absorbance (SUVA) levels. As the molecular weight of the fractions decreased, the TTHM yield coefficients increased. The NOM fractions with AMW values less than 1 K had lower SUVA values (<3 L/mg·m) for all treatment stages and also they had higher yield of TTHM per unit of DOC. The NOM fraction with AMW < 1 K for chlorinated raw water samples has the highest yield coefficient (42 μg-TTHM/mg-DOC).


2012 ◽  
Vol 12 (5) ◽  
pp. 648-657
Author(s):  
T. I. Nkambule ◽  
R. W. M. Krause ◽  
J. Haarhoff ◽  
B. B. Mamba

The removal of natural organic matter (NOM) from water is becoming increasingly important in order to prevent the formation of carcinogenic disinfection by-products (DBPs). The inadequate removal of NOM has a bearing on the capacity of other treatment processes to remove organic micro-pollutants or inorganic species that may be present in water. In order to effectively study the nature of South African water sources in terms of their NOM composition, water samples were collected from drinking water treatment plants in the five geographic water regions of South Africa. A raw water sample, an intermediate sample taken before sand filtration and a final sample after sand filtration were collected three times from these water treatment plants at two-month intervals and over three different seasons. Fluorescence excitation-emission matrices (FEEM), biodegradable dissolved organic carbon (BDOC), ultraviolet (UV) characterisation (200–900 nm) and dissolved organic carbon (DOC) analyses were used to characterise the NOM in the water samples. The FEEM and UV results revealed that the samples were composed mainly of non-humic substances with low UV-254 absorbance, while some samples had high humic substances with high UV-254 values. The samples' DOC results were within the range of 3.25–21.44 mg/L carbon, which was indicative of the varying nature of the NOM composition in the regions where samples were collected. The BDOC fraction of the NOM, on the other hand, ranged from 20 to 65%, depending on the geographical location of the sampling site.


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