Fluorescence Properties of the Air- and Freeze-Drying Treatment on Size-Fractioned Sediment Organic Matter

Sediment humic substance (SHS) is a highly heterogeneous and complex organic mixture with a broad molecular weight range. It is the significant component that associates distribution, transport, and biotoxicity of pollutants in a river environment. Air- and freeze-drying sediment pre-treatment may cause different biological activity and may result in different chemical quantities and sediment organic matter. This study collected sediments that received livestock wastewater discharge. The sediments were air- (AD) and freeze-dried (FD). The dried sediment organic matter was extracted with an alkaline solution and separated into three size-fractioned SHS samples. Size-fractioning is an effective method used to differentiate materials, on a molecular level. The bulk solution (<0.45 μm) was designated as BHS, and size-fractioned solutions were identified as LHS (<1 kDa), MHS (1–10 kDa), and HHS (10 kDa-0.45 μm). The AD SHS had a lower dissolved organic carbon (DOC) concentration than the FD SHS for the bulk and individual size-fractioned SHS, but the AD and FD SHS had a similar distribution of organic carbon in the size-fractioned SHS. The AD SHS had higher aromaticity (SUVA254) and an extent of humification (HIX) than the FD SHS. In addition, the high molecular weight SHS (HHS) had a higher SUVA254 but lower HIX than the MHS and LHS. The HHS had significantly lower fulvic acid but had higher humic acid-like substances than the MHS and LHS. This is possibly the reason the LHS had a higher humification degree but lower aromaticity than HHS. The size-fractioned SHS and optical indicators distinguished the difference between the chemical properties when air- or freeze-dried, due to the different degree of biological activities.

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Advanced oxidation processes: flowsheet options for bulk natural organic matter removal

Water Science & Technology Water Supply ◽

10.2166/ws.2004.0068 ◽

2004 ◽

Vol 4 (4) ◽

pp. 113-119 ◽

Cited By ~ 17

Author(s):

C.A. Murray ◽

S.A. Parsons

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Natural Organic Matter ◽

Advanced Oxidation Processes ◽

Advanced Oxidation ◽

Fenton’S Reagent ◽

Fenton's Reagent ◽

Oxidation Processes

Advanced oxidation processes have been reported to have the potential to remove natural organic matter from source waters. Of these Fenton's reagent, photo-Fenton's reagent and titanium dioxide photocatalysis are the three most promising processes. Compared to conventional coagulation/flocculation processes they have higher removal efficiencies in terms of both dissolved organic carbon and UV254 absorbance. Under optimum reaction conditions all three remove over 80% dissolved organic carbon and 0% UV254 absorbance. In addition the enhanced removal of natural organic matter leads to a corresponding reduction in the formation of disinfection by-products following chlorination of the treated water. Advanced oxidation processes give enhanced removal of organic species ranging from low to high molecular weight while coagulation/flocculation is inefficient at removing low molecular weight species. One additional benefit is all three processes produce less residuals compared to conventional coagulation, which is advantageous as the disposal of such residuals normally contributes a large proportion of the costs at water treatment works.

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Molecular weight distribution of organic matter by ozonation and biofiltration

Water Science & Technology ◽

10.2166/wst.2012.484 ◽

2012 ◽

Vol 66 (12) ◽

pp. 2604-2612 ◽

Cited By ~ 3

Author(s):

Yen-Hui Lin

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Organic Molecule ◽

Drinking Water Treatment ◽

Gel Chromatography ◽

Group 4 ◽

Ozone Dose ◽

Experimental Approaches ◽

Group 2

Molecular weight (MW) distribution of organic matter by ozonation and biofiltration was evaluated using gel chromatography. The MW distribution of organic matter by Sephadex G-25 was observed from groups 2 (MW = 1,029–7,031 g/mol) and 3 (MW = 303–1,029 g/mol) shifted to groups 2, 3 and 4 (MW < 303 g/mol) under ozone doses of 0.1 and 0.4 mg O3/mg total organic carbon (TOC). The shift in MW increases as ozone dosage increases. Biofiltration effectively degraded the organic molecule of group 2; however, the biofiltration only slightly degraded the organic molecule of group 4. Increased ozone dose destroyed functional groups C═C in phenolic and C–O in alcoholic compounds and increased UV-insensitive biodegradable organic carbon for subsequent biofiltration. Biofiltration effectively degraded organic compounds of alcohols and alkenes at an ozone dose of 0.1 mg O3/mg TOC. Experimental approaches in this study can be applied to evaluate and diagnose the function of a full-scale process combining ozonation and biofiltration in drinking water treatment plants.

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Influence of organic matter quality on organic matter degradability in river sediments

10.5194/egusphere-egu2020-9015 ◽

2020 ◽

Author(s):

Florian Zander ◽

Julia Gebert ◽

Rob N. J. Comans ◽

Alexander Groengroeft ◽

Timo J. Heimovaara ◽

...

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Pore Water ◽

Chlorophyll Concentration ◽

Sediment Organic Matter ◽

Rheological Parameters ◽

Ammonium Concentration ◽

Organic Matter Quality ◽

Degradation Rates ◽

Physical Density

The project BIOMUD, part of the scientific network MUDNET (www.tudelft.nl/mudnet), investigates the decomposition of sediment organic matter (SOM) in the Port of Hamburg. The microbial turnover of sediment organic matter under reducing conditions leads to the formation of methane, carbon dioxide and others gases causing a change in the sediment rheological parameters. BIOMUD is aiming to explain the effect of organic matter lability on the rheological properties impacting the navigable depth of the harbour.Samples of freshly deposited material were taken in 2018 and 2019 at nine locations in a transect of 30&#160;km through the Port of Hamburg. Analyses included abiotic parameters (among others grain size distribution, standard pore water properties, standard solid properties, stable isotopes, mineral composition) and biotic parameters (among others anaerobic and aerobic organic matter degradation, DNA, protein and lipid content, microbial population). At four locations, physical density fractions and chemical organic matter fractions were analysed.The quality of organic matter was described by normalising carbon released from microbial degradation under both aerobic and anaerobic conditions to the share of total organic carbon (mg C/g TOC). Organic matter pools with different degradation rates were used to quantify the lability of organic matter. The share of faster degradable (more labile) pools correlated strongly with the size of the hydrophilic DOC fraction, confirming results of Straathof et al. (2014) who investigated dissolved organic carbon pools in compost. The hydrophilic DOC fraction was closely correlated to the polysaccharide concentration, explaining the input of easily degradable organic matter. Moreover, the amount of organic carbon present in the sediment&#8217;s light density fraction < 1.4 g/cm3 strongly correlated with the hydrophilic DOC fraction and, less strongly, with organic matter lability. High organic matter quality, i.e. the labile, easily degradable fraction, was further related to the chlorophyll concentration in the water column but also the ammonium concentration in the sediment&#8217;s pore water.It was hypothesised that the observed toposequence of decreasing organic matter quality from upstream to downstream could be explained by a chronosequence of increasing degradation and therefore ageing of organic matter as the sediment passes through the harbour area. Further, it was hypothesized that the harbour received organic matter of higher degradability, originating from phytoplankton biomass, from the upstream part of the Elbe river, whereas the input from the tidal downstream area provided organic matter of lower quality (degradability).This study was funded by Hamburg Port Authority.

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EXTRACTION DES ACIDES FULVIQUES D'UN HORIZON SPODIQUE PAR UNE RESINE ECHANGEUSE D'IONS DE TYPE H POSITIF

Canadian Journal of Soil Science ◽

10.4141/cjss71-022 ◽

1971 ◽

Vol 51 (2) ◽

pp. 157-164

Author(s):

G. HUBERT ◽

A. GONZALEZ

Keyword(s):

Organic Matter ◽

Fulvic Acid ◽

Freeze Drying ◽

Gel Filtration ◽

Fulvic Acids ◽

Ash Content ◽

Freeze Dried ◽

Efficient Reagent

A resin in the H+ form (Dowex 50W-X8) was used to extract fulvic acids from a Spodic horizon. This resin has the following advantages in relation to the reagents normally used. It solubilizes organic matter while purifying it and without altering it by oxidation and hydrolysis. Furthermore, since the resin is eliminated completely from the extract, no contaminating ions remain. The soil was agitated in a mixture of water and resin. The extract obtained was filtered, centrifuged, purified by passage through a column of H+ resin and freeze-dried. The alternation of freeze-drying and resolubilization resulted in the coagulation of the silica which was removed by centrifugation. Acid organic matter with very low ash content (1%) was obtained. The fulvic acids extracted by resin and by Na-pyrophosphate were compared. Qualitatively they were practically the same, as evidenced by the similarity of the curves obtained by gel-filtration (Sephadex). Quantitatively the resin, however, was a more efficient reagent. Therefore, it is recommended for the extraction of fulvic acid and organo-mineral complexes.

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Removal of Natural Organic Matter (NOM) from Drinking Water Supplies by Ozone-Biofiltration

Water Science & Technology ◽

10.2166/wst.1999.0466 ◽

1999 ◽

Vol 40 (9) ◽

pp. 157-163 ◽

Cited By ~ 29

Author(s):

Raymond M. Hozalski ◽

Edward J. Bouwer ◽

Sudha Goel

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Natural Organic Matter ◽

Laboratory Experiments ◽

Low Molecular Weight ◽

Batch Experiments ◽

Toc Removal ◽

High Molecular Weight Material ◽

Effects Of Temperature

Removal of natural organic matter (NOM) in biofilters can be affected by many factors including NOM characteristics, use of pre-ozonation, water temperature, and biofilter backwashing. Laboratory experiments were performed and a biofilter simulation model was developed for the purpose of evaluating the effects of each of these factors on NOM removal in biofilters. Four sources of NOM were used in this study to represent a broad spectrum of NOM types that may be encountered in water treatment. In batch experiments with raw NOM, the removal of organic carbon by biodegradation was inversely proportional to the UV absorbance (254 nm)-to-TOC ratio and directly proportional to the percentage of low molecular weight material (as determined by ultrafiltration). The extent and rate of total organic carbon (TOC) removal typically increased as ozone dose increased, but the effects were highly dependent on NOM characteristics. NOM with a higher percentage of high molecular weight material experienced the greatest enhancement in biodegradability by ozonation. The performance of laboratory-scale continuous-flow biofilters was not significantly affected by periodic backwashing, because backwashing was unable to remove large amounts of biomass from the filter media. Model simulations confirmed our experimental results and the model was used to further evaluate the effects of temperature and backwashing on biofilter performance.

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A novel approach to quantifying resuspension resistance of sediment organic matter against coastal flow

10.5194/egusphere-egu2020-15864 ◽

2020 ◽

Author(s):

Naiyu Zhang ◽

Charlotte Thompson ◽

Ian Townend

Keyword(s):

Organic Matter ◽

Organic Carbon ◽

Marine Sediments ◽

Microcomputed Tomography ◽

Sediment Organic Matter ◽

Flow Conditions ◽

X Ray ◽

Continental Shelves ◽

Sediment Organic Carbon ◽

Organo Clay

In order to estimate sediment organic carbon budget in coastal oceans and continental shelves, a first step is to estimate how much of the deposited organic matter is retained within a sediment matrix, for further remineralization and preservation on a geological timescale, rather being physically flushed away by benthic flow1. This question becomes more challenging for the regions where &#8216;mobile&#8217; layers (e.g. fluff layer, fluid mud and nepheloid layer) are formed due to the massive organic matter inputs, and often frequent resuspension and deposition2. Organic matter remineralization and preservation in sediments has been mostly investigated but often overlooks the role of flow-induced shear stresses on suspending the organic matter. While such flow influences in sediment organic matter budget may have little influence on sediment organic matter budget in deep oceans, it cannot be neglected in shallow-water coastal seas and continental shelves where cyclic resuspension, deposition and frequent storm events occur3,4. To our knowledge, the resistance strengths of organic matter in sediments against flow resuspension has received little attention.To investigate this knowledge gap, various organo-clay aggregates and organo-clay-sand aggregates formed under different flow conditions were investigated by a series of laboratory flume5 and high resolution X-ray Microcomputed Tomography (micro-CT) experiments6. Herein, a novel methodology is proposed, which successfully establishes quantitative relationships between the resuspension resistance strengths of these organic aggregates and a wide range of flow intensities, from moderate to storm conditions. The results provide a basis for computing resuspension under a range of flow conditions and, hence improving estimates of the organic matter budget in the coastal zone. &#160;&#160;References<ol><li>Burdige, D. J. Preservation of organic matter in marine sediments: Controls, mechanisms, and an imbalance in sediment organic carbon budgets? Chem. Rev. 107, 467&#8211;485 (2007).</li> <li>McKee, B. A., Aller, R. C., Allison, M. A., Bianchi, T. S. & Kineke, G. C. Transport and transformation of dissolved and particulate materials on continental margins influenced by major rivers: Benthic boundary layer and seabed processes. Cont. Shelf Res. (2004). doi:10.1016/j.csr.2004.02.009</li> <li>Burdige, D. J. Burial of terrestrial organic matter in marine sediments: A re-assessment. Global Biogeochem. Cycles 19, 1&#8211;7 (2005).</li> <li>Nicholls, R. J. & Cazenave, A. Sea-level rise and its impact on coastal zones. Science (2010). doi:10.1126/science.1185782</li> <li>Thompson, C. E. L., Couceiro, F., Fones, G. R. & Amos, C. L. Shipboard measurements of sediment stability using a small annular flume-core mini flume (cmf). Limnol. Oceanogr. Methods (2013). doi:10.4319/lom.2013.11.604</li> <li>Zhang, N. et al. Nondestructive 3D Imaging and Quantification of Hydrated Biofilm-Sediment Aggregates Using X-ray Microcomputed Tomography. Environ. Sci. Technol. 52, 13306&#8211;13313 (2018).</li> </ol>

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Measuring dissolved organic matter in estuarine and marine waters: size-exclusion chromatography with various detection methods

Environmental Chemistry ◽

10.1071/en18108 ◽

2018 ◽

Vol 15 (7) ◽

pp. 436 ◽

Cited By ~ 3

Author(s):

Gabriel Dulaquais ◽

Johann Breitenstein ◽

Matthieu Waeles ◽

Rémi Marsac ◽

Ricardo Riso

Keyword(s):

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Dissolved Organic Matter ◽

Humic Substances ◽

Size Exclusion Chromatography ◽

Size Exclusion ◽

Marine Waters ◽

Wide Range ◽

Exclusion Chromatography

Environmental contextDissolved organic matter (DOM), a key parameter in aquatic biogeochemistry, is difficult to characterise owing to its variable composition and structure. We report a chromatographic method with carbon, nitrogen and absorbance detection able to record the size distribution of DOM and changes in its composition. The method could be used to identify additional sources to river or coastal waters as well as monitoring the DOM size/reactivity continuum in open oceans. AbstractWe studied the performance and limitations of size-exclusion chromatography with organic carbon, ultraviolet and organic nitrogen detectors (SEC-OCD-UVD-OND) for characterising dissolved organic matter (DOM) in estuarine and marine waters. We identified a strong salt effect on dissolved organic carbon (DOC) determination; however, calibration gave good results at salinity levels close to those of the sample analysed (ΔS ± 2 psu (practical salinity units)), with limited matrix effects, enabling an accurate measurement of DOC, as demonstrated by an intercalibration exercise. The repeatability, reproducibility and limit of detection (3 ppb for both carbon and nitrogen) for the three detectors demonstrated the robustness of the method for a wide range of natural waters, including carbon-rich freshwaters and deep seawaters with low carbon content (6000 ppb-C to 300 ppb-C). Deeper analysis of the SEC demonstrated that proteins and polysaccharides are partly fractionated within the column, and that terrestrial humic substances, isolated on a XAD-8 resin, can also be eluted in both fractions associated with biopolymers and low-molecular-weight neutrals. Application of the method to the study of DOM along a macrotidal estuary that was influenced by agricultural activities revealed significant changes in its composition despite a conservative DOC distribution. Distinct origins and qualities of high-molecular-weight (>500 kDa) organic compounds were identified for riverine and marine end-members. A new diagram to track changes in DOM lability is proposed to complete the humic-substances diagram.

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Spatiotemporal Characterization of Chromophoric Dissolved Organic Matter (CDOM) and CDOM-DOC Relationships for Highly-Polluted River

10.20944/preprints201608.0193.v1 ◽

2016 ◽

Author(s):

Sijia Li ◽

Jiquan Zhang ◽

Guangyi Mu ◽

Hanyu Ju ◽

Rui Wang ◽

...

Keyword(s):

Water Quality ◽

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Dissolved Organic Matter ◽

Ternary Phase Diagram ◽

Spectral Characteristics ◽

River Watershed ◽

Sampling Locations ◽

Polluted Waters

Spectral characteristics of CDOM in water column are a key parameter for bio-optical modeling. Knowledge of CDOM optical properties and spatial discrepancy based on the relationship between water quality and spectral parameters in Yinma River watershed with in situ data collected highly-polluted waters are exhibited in this study. Seasonal field data sets collected over a period of 2 months in 2015 in Yinma River Watershed. Based on the comprehensive index method, the riverine waters showed serious contamination, especially the COD, Fe, Mn, Hg and DO were out of range contamination warning. Dissolved organic carbon (DOC) and total suspended matter (TSM) with prominent non-homogenizing were significantly high in the riverine waters, but chlorophyll-a (Chl-a) was opposite. Ternary phase diagram showed that non-algal paritcles absorption played an important role in total non-water light absorption (>50%) in most sampling locations, and mean contribution of CDOM were 13% and 22% in summer and autumn respectively. Analysis of ratio of absorption at 250-365 nm (E250:365) and spectral slope (S275-295) indicated that CDOM had higher aromaticity and molecular weight in autumn than in summer, is consistent with the results of water quality and relative contribution. Redundancy analysis (RDA) indicated that the environmental variables OSM had a strong correlation with CDOM absorption, followed by heavy metal, e.g., Mn, Hg and Cr6+. However, for the specific UV absorbance (SUVA254), the seasonal values showed opposite results compared with the reported literature. The potential reasons were the more UDOM (uncolored Dissolved Organic Matter) from human source (wastewater effluent) existed in waters. Terrigenous inputs simultaneously are in relation to the aCDOM(440)-DOC relationship with the correlation coefficient was 0.90 in summer (2-tailed, p<0.01), and 0.58 in autumn (2-tailed, p<0.05). Spatial distribution of CDOM parameters exhibited that the downstream regions focused on dry land have high CDOM molecular weight and aromatic hydrocarbon. Partial sampling locations around the cities or countries generally showed abnormal values due to terrigenous inputs. As a bio-optical model parameter, spectral characteristic of CDOM is helpful in adjusting the derived algorithms in highly-polluted environments. The study on organic carbon and pollutants in highly-polluted waters had an important contribution to global carbon balance estimation and water environment protection.

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Novel Ingredients Based on Grapefruit Freeze-Dried Formulations: Nutritional and Bioactive Value

Foods ◽

10.3390/foods8100506 ◽

2019 ◽

Vol 8 (10) ◽

pp. 506 ◽

Cited By ~ 2

Author(s):

Marta Igual ◽

Laura Cebadera ◽

Rosa Mᵃ Cámara ◽

Claudia Agudelo ◽

Nuria Martínez-Navarrete ◽

...

Keyword(s):

Molecular Weight ◽

Antioxidant Capacity ◽

High Molecular Weight ◽

Freeze Drying ◽

Natural Fibers ◽

Gum Arabic ◽

Bamboo Fiber ◽

Microwave Drying ◽

Food Ingredients ◽

Freeze Dried

Grapefruit is a fruit with interesting nutritional value and functional properties, but a short life. Freeze-drying (FD) is a valuable technique as it produces high-quality dehydrated products. This study is aimed to obtain new food ingredients based on freeze-dried grapefruit formulated with high molecular weight solutes (gum arabic and bamboo fiber) in three different proportions (F1, F2, and F3). To improve the FD, a mild microwave drying pre-treatment was applied. Influence of the water content and the presence of high molecular weight solutes on freeze-drying kinetics was tested by Midilli-Kucuk and Page models. The best FD kinetic model fit on grapefruit powders were Midilli-Kucuk for F2 and F3, and Page for F1, and the adequate freeze-drying times for F1, F2, and F3 were 24, 16, and 18 h, respectively. Final samples were evaluated for nutritional and antioxidant capacity. Gum arabic and bamboo fiber present a protector effect, which results in a significant antioxidant capacity due to the protection of flavonoids and antioxidant vitamins. These novel food ingredients could be of great interest for the food industry in order to develop foods with improved antioxidant capacity as well as enriched in natural fibers and/or micronutrients.

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Effect of O3 and O3/H2O2 on algae harvesting using chitosan

Water Science & Technology ◽

10.2166/wst.2013.001 ◽

2013 ◽

Vol 67 (6) ◽

pp. 1294-1301 ◽

Cited By ~ 7

Author(s):

R. Pranowo ◽

D. J. Lee ◽

J. C. Liu ◽

J. S. Chang

Keyword(s):

Hydrogen Peroxide ◽

Molecular Weight ◽

Organic Matter ◽

Organic Carbon ◽

Dissolved Organic Carbon ◽

Weight Distribution ◽

Separation Efficiency ◽

Polyaluminum Chloride ◽

Floc Size ◽

Extracellular Organic Matter

We examined the effects of pre-oxidation using ozone (O3) and a combination of O3 and hydrogen peroxide (O3/H2O2) on algae suspensions and their harvesting. Inactivation of algae cells, release of intracellular organic matter (IOM), mineralization of extracellular organic matter (EOM), and changes in molecular weight distribution of EOM were found after pre-oxidation. Enhanced separation efficiency of turbidity, dissolved organic carbon (DOC), protein, and polysaccharide using chitosan and polyaluminum chloride (PACl) was found after pre-oxidation, especially when algae cells were subject to O3/H2O2. Chitosan showed higher efficiency than PACl. Judging from the remarkable increase in floc size, it was proposed that released IOM formed complexes with cationic chitosan and resulted in enhanced dual flocculation and facilitated algae separation.

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