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Fulvic acid

Liqiang Meng, Shumei Zhang, Hainan Gong, Xiancheng Zhang, Chuandong Wu, Weiguang Li
The effects of spent mushroom substrate (SMS) and sucrose (S) amendment on emissions of nitrogenous gas (mainly NH3 and N2O) and end products quality of sewage sludge (SS) composting were evaluated. Five treatments were composted for 20 days in laboratory-scale using SS with different dosages of SMS and S, without additive amended treatment used as control. The results indicated that SMS amendments especially combination with S promoted dehydrogenase activity, CO2 production, organic matter degradation and humification in the composting, and maturity indices of composting also showed that the 30%SMS+2%S treatment could be much more appropriate to improve the composting process, such as total Kjeldahl nitrogen, nitrification index, humic acids/fulvic acids ratio and germination index, while the emissions of NH3 and N2O were reduced by 34...
January 4, 2018: Bioresource Technology
Charlotta Tiberg, Carin Sjöstedt, Jon Petter Gustafsson
While metal sorption mechanisms have been studied extensively for soil surface horizons, little information exists for subsoils, for example Spodosol Bs horizons. Here the sorption of cadmium(II), copper(II) and lead(II) to seven Bs horizons from five sites was studied. Extended X-ray absorption fine structure (EXAFS) spectroscopy showed that cadmium(II) and lead(II) were bound as inner-sphere complexes to organic matter. Addition of o-phosphate (to 1 μmol l-1) did not result in any significant enhancement of metal sorption, nor did it influence EXAFS speciation...
January 4, 2018: Chemosphere
Juan Xiong, Liping Weng, Luuk Koopal, Mingxia Wang, Zhihua Shi, Li-Rong Zheng, WenFeng Tan
The effect of adsorbed soil fulvic (JGFA) and humic acid (JGHA) on Pb binding to goethite was studied with the Ligand Charge Distribution (LCD) model and the X-ray absorption fine structure (XAFS) spectroscopy analysis. In LCD model, the adsorbed small JGFA particles were evenly located in the Stern layer, but the large JGHA particles were distributed over the Stern layer and the diffuse layer which mainly depended on the JGHA diameter and concentrations. Specific interactions of HS with goethite were modeled by inner-sphere complexes between -FeOH2+0...
January 10, 2018: Environmental Science & Technology
Chenyi Yuan, Yu-Ping Chin, Linda K Weavers
Iron (Fe) plays a critical role in the formation of hydroxyl radical (OH) which may participate in the indirect photodegradation of aquatic contaminants. While Fe photochemistry has been extensively studied, the efficacy of iron amendments for contaminant attenuation in sunlit natural waters has not been well researched. We studied the efficacy of this approach by monitoring OH induced acetochlor (AC) degradation and determining OH production rates with terephthalate (TPA) as a probe. Surface wetland waters as well as model fulvic acid (FA) solutions were amended with Fe(III) salt at different concentrations at pH values of 2...
November 27, 2017: Water Research
Guangchun Shan, Haoyuan Lu, Qunliang Li
The purpose of this research was to evaluate the properties and dynamic changes of humic acids (HA), fulvic acids (FA), hydrophobic neutrals (HoN), and hydrophilic (Hi) fractions of dissolved organic matter (DOM) during food waste and sugarcane leaves co-composting process. The pools of HA, FA, HoN, and Hi were separated from DOM by fractionation method, and characterized using spectroscopic (UV-vis, FTIR) and pyrolysis-GC/MS analyses. The least peaks in the HA pool were found in FTIR spectra with the simple structure in HA...
December 26, 2017: Environmental Science and Pollution Research International
Ruei-Feng Shiu, Chon-Lin Lee, Wei-Chun Chin
Rivers drive large amounts of terrestrial and riverine organic matter into oceans. These organic materials may alter the self-assembly of marine dissolved organic matter (DOM) polymers into microgels and can even affect the behavior of existing natural microgels. We used Suwannee River humic acid, fulvic acid, and natural organic matter as a model of riverine organic matter (ROM) to investigate the impacts of ROM input on DOM polymer and microgel conversion. Our results indicated that the release of extra ROM, even at low concentrations (0...
December 15, 2017: Water Research
Ankit Pathak, Amy Pruden, John T Novak
Landfill leachate typically contains UV-quenching organics, which hinder disinfection at POTWs. This study tested a 2-stage submerged AnMBR for the degradation of UV-absorbing compounds in landfill leachate. Leachate was treated in a thermophilic reactor (55 ± 2 °C) followed by a mesophilic AnMBR (37 ± 1 °C), with HRTs of 25 ± 5 days and 40 ± 5 days respectively. Solids were not wasted, in order to promote biomass accumulation. COD, Organic carbon, and UV254 absorbance were monitored over 13 months of operation...
December 18, 2017: Bioresource Technology
YounJung Jung, George Metreveli, Chang-Beom Park, Seungyun Baik, Gabriele E Schaumann
Citrate (Cit) and polyethylenimine (BPEI)-coated silver nanoparticles (AgNPs) were used to understand how the type of capping agents and surface charge affect their colloidal stability, dissolution, and ecotoxicity in the absence/presence of Pony Lake Fulvic Acid (PLFA). In the presence of PLFA, Cit-AgNPs were stabilized, while BPEI-AgNPs were aggregated. The aggregation of BPEI-AgNPs decreased with the time and their stabilizing effect increased at high PLFA concentration. The dissolution also differed between both AgNPs and was influenced by the PLFA concentration...
December 19, 2017: Environmental Science & Technology
Devin A Rippner, Peter G Green, Thomas M Young, Sanjai J Parikh
With increasing demand for recycled wastewater for irrigation purposes, there is a need to evaluate the potential for manufactured nanomaterials in waste water to impact crop production and agroecosystems. Copper oxide nanoparticles (CuO NPs) have previously been shown to negatively impact the growth of duckweed (Landoltia punctata) a model aquatic plant consumed by water fowl and widely found in agricultural runoff ditches in temperate climates. However, prior studies involving CuO NP toxicity to duckweed have focused on systems without the presence of dissolved organic matter (DOM)...
December 11, 2017: Environmental Pollution
Patrycja Boguta, Zofia Sokołowska, Kamil Skic
Thermogravimetry-coupled with differential scanning calorimetry, quadrupole mass spectrometry, and Fourier-transform infrared spectroscopy (TG-DSC-QMS-FTIR)-was applied to monitor the thermal stability (in an N2 pyrolytic atmosphere) and chemical properties of natural polymers, fulvic (FA) and humic acids (HA), isolated from chemically different soils. Three temperature ranges, R1, 40-220°C; R2, 220-430°C; and R3, 430-650°C, were distinguished from the DSC data, related to the main thermal processes of different structures (including transformations without weight loss)...
2017: PloS One
Shi Chen, Jing Deng, Lei Li, Naiyun Gao
This study evaluated the effect of low-pressure ultraviolet (UV) irradiation on the formation of disinfection by-products (DBPs) from algal organic matter of Microcystis aeruginosa during subsequent chlorination and chloramination. The algal organic matter includes extracellular organic matter (EOM) and intracellular organic matter (IOM). The fluorescence excitation-emission matrix spectra indicated that the humic/fulvic acid-like organics of EOM and the protein-like organics of IOM may be preferentially degraded by UV treatment...
December 13, 2017: Environmental Science and Pollution Research International
Juan Zhang, Shu-Kai Fan, Ming-Hua Zhang, Michael L Grieneisen, Jian-Feng Zhang
Aliphatic hydrocarbons (AHs) are major petroleum contaminants in the environment. In this study, the AHs bound to various soil endogenetic humus fractions were separated through successive extraction. Most of the AHs (46.1%) in soils were adsorbed onto/into humic acids (HA) and a small quantity of AHs (9.6%) were organic solvent extractable. AHs in B. chinensis were also analyzed since their potential risks to the residents through ingestion. AHs from C21 to C34, so called high molecular weight AHs (HMWAHs), were dominant AHs in B...
December 6, 2017: Journal of Hazardous Materials
Chunmei Chen, Aaron Thompson
Abiotic Fe(II) oxidation by O2 commonly occurs in the presence of mineral sorbents and organic matter (OM) in soils and sediments, however this tertiary system is rarely studied. Therefore, we examined the impacts of mineral surfaces (goethite and γ-Al2O3) and organic matter (Suwannee River Fulvic Acid, SRFA) on Fe(II) oxidation rates and the resulting Fe(III) (oxyhydr)oxides under 21% and 1% pO2 at pH 6. We tracked Fe dynamics by adding 57Fe(II) to 56Fe-labeled goethite and γ-Al2O3, and characterized the resulting solids using 57Fe Mössbauer spectroscopy...
December 1, 2017: Environmental Science & Technology
Dongqing Zhang, Antoine Prandota Trzcinski, Jinxue Luo, David C Stuckey, Soon Keat Tan
In this study, the production, composition, and characteristics of dissolved organic matter (DOM) in an anoxic-aerobic submerged membrane bioreactor (MBR) were investigated. The average concentrations of proteins and carbohydrates in the MBR aerobic stage were 3.96 ± 0.28 and 8.36 ± 0.89 mg/L, respectively. After membrane filtration, these values decreased to 2.9 ± 0.2 and 2.8 ± 0.2 mg/L, respectively. High performance size exclusion chromatograph (HP-SEC) analysis indicated a bimodal molecular weight (MW) distribution of DOMs, and that the intensities of all the peaks were reduced in the MBR effluent compared to the influent...
November 27, 2017: Environmental Science and Pollution Research International
Irmina Ćwieląg-Piasecka, Maciej Witwicki, Maria Jerzykiewicz, Julia Jezierska
Radical oxidation of carbamate insecticides, namely carbaryl and carbofuran, was investigated with spectroscopic (electron paramagnetic resonance [EPR] and UV-Vis) and theoretical (density functional theory [DFT] and ab initio orbital-optimized spin-component scaled MP2 [OO SCS MP2]) methods. The two carbamates were subjected to reaction with •OH, persistent DPPH• and galvinoxyl radical, as well as indigenous radicals of humic acids. The influence of fulvic acids on carbamate oxidation was also tested. The results obtained with EPR and UV-Vis spectroscopy indicate that carbamates can undergo direct reactions with various radical species, oxidizing themselves into radicals in the process...
November 24, 2017: Environmental Science & Technology
Juliana Valle, Michael Gonsior, Mourad Harir, Alex Enrich-Prast, Philippe Schmitt-Kopplin, David Bastviken, Ralf Conrad, Norbert Hertkorn
Dissolved organic matter (DOM) contained in lake sediments is a carbon source for many microbial degradation processes, including aerobic and anaerobic mineralization. During anaerobic degradation, DOM is partially consumed and transformed into new molecules while the greenhouse gases methane (CH4) and carbon dioxide (CO2) are produced. In this study, we used ultrahigh resolution mass spectrometry to trace differences in the composition of solid-phase extractable (PPL resin) pore water DOM (SPE-DOM) isolated from surface sediments of three boreal lakes before and after 40 days of anoxic incubation, with concomitant determination of CH4 and CO2 evolution...
November 7, 2017: Water Research
Wenlu Li, Peng Liao, Trey Oldham, Yi Jiang, Chao Pan, Songhu Yuan, John D Fortner
Natural organic matter (NOM) is ubiquitous in aqueous systems and dynamically partitions onto/from environmental surfaces. However, such interfacial processes have not been uniformly quantified in situ and in real time. In this work, adsorption and deposition processes of Suwannee River humic acid (SRHA) and Suwannee River fulvic acid (SRFA), as model NOM, were evaluated for a series of environmentally relevant interfaces. Real-time, interfacial phenomenon, including deposition, release, and adlayer viscoelastic properties, were quantified over a variety of water chemistries via quartz crystal microbalance with dissipation monitoring (QCM-D)...
November 9, 2017: Water Research
Khalid Azim, Youssef Faissal, Brahim Soudi, Claude Perissol, Sevastianos Roussos, Imane Thami Alami
More than 1 million tons of fresh organic wastes is produced in the Souss-Massa region in Morocco. Tomato organic residues represent more than 25% of the total organic wastes and are deposited in uncontrolled landfills. Thus, composting can represent a valuable and pertinent solution to this environmental problem. The objectives of this experiment are to identify the potential functional groups responsible for compost phytotoxicity and to determine the optimum initial carbon to nitrogen ratio (C/N) for maximum recovery of tomato residues...
November 19, 2017: Environmental Science and Pollution Research International
Lei Wang, Ying-Jun Li, Ying Xiong, Wen-Bing Tan, Lie-Yu Zhang, Xiang Li, Xiao-Shu Wang, Jian-Feng Xu, Tong-Tong Li, Jin-Sheng Wang, Ming-Xuan Cai, Bei-Dou Xi, Di-Hua Wang
The performance of the Sha-he wastewater reclamation plant was evaluated in this study. To remove residual nitrogen after Anaerobic-Anoxic-Oxic (A2O) treatment, three multistage Anoxic-Oxic (A/O) were added to investigate the nitrogen removal efficiency and its mechanism. In addition, the constituents and evolution of dissolved organic matter (DOM) during wastewater reclamation was also investigated using a method combining fluorescence spectroscopy with fluorescence regional integration (FRI). The results suggested that multistage A/O treatment can effectively improve the nitrogen removal ability under low concentrations of carbon sources...
2017: PloS One
Khan M G Mostofa, Wen Li, Fengchang Wu, Cong-Qiang Liu, Haiqing Liao, Li Zeng, Min Xiao
Sediment pore waters were examined in four Chinese lakes (Bosten, Qinghai, Chenghai and Dianchi) to characterise the sources of dissolved organic matter (DOM) and their microbial changes in the sediment depth profiles. Parallel factor (PARAFAC) modelling on the sample fluorescence spectra confirmed that the pore water DOM was mostly composed of two components with a mixture of both allochthonous and autochthonous fulvic acid-like substances in three lakes, except Lake Dianchi, and protein-like components in Lake Bosten...
November 15, 2017: Environmental Science and Pollution Research International
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