CPMAS 13 C NMR characterization of humic acids from composted agricultural Saudi waste

Al-Faiyz, Yasair S.

doi:10.1016/j.arabjc.2012.12.018

Cited by 49 publications

(30 citation statements)

References 67 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This trend has also been observed in previous studies [19]. The microbial residue formed by A. niger in the fluid medium of cellulose contained no anomeric C signal, unlike the humic acid investigated by Al-Faiyz [16]. The microbial residue derived from lignin had a higher proportion of alkyl C groups, which was mostly due to the accumulation of recalcitrant structural components in the microbial residue derived from lignin, such as those of waxes, cutin, suberin, lipids, and amino acids.…”

Section: Discussionsupporting

confidence: 87%

“…The distributions of different C species were determined from the relative contributions of the signal intensities (Table 5). Both C-An and L-An exhibited weak peaks near 24 ppm due to methyl C (CH3) and methylene C (CH2)n [16]. According to the explanation by Joanisse et al [17], the peak at 30 ppm mainly represents -CH2 groups in long chains derived from cutin, suberin and plant waxes.…”

Section: C Cp-mas Nmr Spectra Of Microbial Residuementioning

confidence: 92%

“…The weak peak was centred near 129 ppm, indicating carbons in a ring with a strong electron donor, such as O or N. The largest peak in the carbonyl-C region was at 175 ppm and was ascribed to the amide-C of proteins and the carboxyl groups of microbial lipids. The relative areas were calculated as the percentage of the total intensity from the integral curves of the following C chemical-shift regions: alkyl C (0~45 ppm), O-alkyl C (45~110 ppm), methoxy C (50~60 ppm), aromatic C (110~140 ppm), phenolic C (140~160 ppm), carboxyl C (160~190 ppm) [18,19] and carbonyl C (190~220 ppm) [16,19]. Compared with L-An, C-An had larger proportions of O-alkyl C and carbonyl-C, and smaller proportions of alkyl C, aromatic C, phenolic C and carboxyl C. The aromaticity index (%) and hydrophobic C/hydrophilic C and alkyl-C/O-alkyl-C ratios of C-An were all less than those of L-An.…”

Section: C Cp-mas Nmr Spectra Of Microbial Residuementioning

confidence: 99%

See 2 more Smart Citations

Contribution of Microbial Residues Obtained from Lignin and Cellulose on Humus Formation

Wang

et al. 2019

Sustainability

View full text Add to dashboard Cite

The contribution of microbial residues formed on lignin and cellulose to the formation of humus (HS) was investigated. The microbial residues formed by Aspergillus niger (A. niger) in the cultures of cellulose and lignin in a fluid medium were structurally characterized by elemental analysis, differential thermal analysis (DTA), FTIR spectroscopy and CP/MAS 13 C NMR spectroscopy. Compared to cellulose itself, the microbial residue from cellulose contains more aromatic compounds and N-containing compounds and fewer carbohydrates and carboxylic compounds. A. niger improved the thermal stability and aromaticity of the cellulose. However, compared with that on lignin, more N-containing compounds, carbohydrates and carboxylic acid derivatives and less aromatic material were found in the microbial residue from lignin. Regardless of whether the carbon source was cellulose or lignin, A. niger utilized the N in the fluid medium to synthesize its own cells, and eventually, they could transfer the N into the microbial residue; in addition, the O-alkyl species dominated over the alkyl and aromatic compounds in the microbial residue. Although the molecular structures of the components of the microbial residue from lignin tended to be simpler, they were more alkylated, more hydrophobic and less aliphatic than those from cellulose. During culture with A. niger, the cellulose underwent degradation and then a polymerization, which led to an increased degree of condensation but a lower degree of oxidation, providing essential precursor substances for HSs formation. However, lignin underwent oxidative degradation. The microbial residue from lignin had a lower degree of condensation and a higher degree of oxidation.

show abstract

Section: Discussionsupporting

confidence: 87%

Section: C Cp-mas Nmr Spectra Of Microbial Residuementioning

confidence: 92%

Section: C Cp-mas Nmr Spectra Of Microbial Residuementioning

confidence: 99%

See 1 more Smart Citation

Contribution of Microbial Residues Obtained from Lignin and Cellulose on Humus Formation

Wang

et al. 2019

Sustainability

View full text Add to dashboard Cite

show abstract

“…22,23,24 It must be described by model structures because its complexity, exactly in the same way as for the humic and fulvic acids extracted from soils and lake sediments. 25,26 In other words, it is completely reasonable to assume for the humic and fulvic matter from landfill leachate a structural analogy with that extracted from soil and other fluvial or lake sediments. This assumption is anyway substantiated by a series of experimental data.…”

Section: Resultsmentioning

confidence: 99%

Successful Landfill Leachate Wastewater Treatment Using the Sequence of Ozonation, Adsorption on Charcoal and Photo-Ozonolysis

Cataldo

2018

ECB

View full text Add to dashboard Cite

Landfill leachate derived from the landfilling practice of the municipal wastes is a problem affecting all countries and continents. Even after the shutdown of a landfill site, the leachate production continues for decades. In this work a solution for the landfill lea chate treatment has been proposed based on three fundamental steps: the pre-ozonolysis of the leachate, the passage of the ozonized leachate through a fixed bed of activated carbon and the final step consisting in a photo-ozonolysis stage involving the simultaneous action of ozone and UV light. A distinction between the chemical structure and chemical behaviour of young and mature leachate was evidenced by thermal analysis of the soluble organic matter (SOM) obtained from these substrates. Furthermore, a distinction between young and mature leachate was also evidenced in terms of their different reactivity toward ozone as illustrated by the COD abatement and by FTIR spectroscopy on pristine and ozonized SOM. A modular pilot plant for the treatment of different landfill leachates was presented and proposed.

show abstract

“…Regarding the carbonyl region (190-220 ppm), there were no appreciable signals in these amendments, except a low PB content. Other authors have also reported the absence of carbonyl groups, attributed to aldehydes, ketones, and quinones, in humic substances [31].…”

Section: Solid State 13 C Cpmas Nmr Spectramentioning

confidence: 91%

Evaluation of Commercial Humic Substances and Other Organic Amendments for the Immobilization of Copper Through 13C CPMAS NMR, FT-IR, and DSC Analyses

et al. 2019

View full text Add to dashboard Cite

The application of organic amendments to contaminated agricultural lands can immobilize metals and improve soil conditions. The chemical structures and long-term stability of commercial humic substances and other composted organic amendments (sheep and horse manure, vermicompost, pine bark, and pruning waste) were analyzed using 13C CPMAS NMR, FT-IR, and DSC to evaluate their use in soil remediation. The interactions of humic substances and manure with Cu (0 and 5000 mg kg−1) at different pH (2.5 and 5.0) were studied through a batch adsorption experiment observing the changes in their molecular structure using spectroscopic techniques. Humic substances exhibited high aromaticity and phenolic and carboxylic group content, with great affinity for Cu complexation. Humic substances and pruning waste were the most stable due to their high recalcitrant organic matter contents, whereas manure was the least stable, given the labile nature of its organic matter content. There were considerable changes in the carboxylic and phenolic groups of humic substances with pH, and also with Cu, albeit in a lesser extent, especially at pH 5.0, suggesting the great sorption capacity of humic substances and the key role of pH and these functional groups in metal complexation. Manure did not exhibit such changes. Commercial humic substances could be useful amendments for the remediation of contaminated agricultural soils due to their high sorption capacities and long-term stability.

show abstract

CPMAS 13 C NMR characterization of humic acids from composted agricultural Saudi waste

Cited by 49 publications

References 67 publications

Contribution of Microbial Residues Obtained from Lignin and Cellulose on Humus Formation

Contribution of Microbial Residues Obtained from Lignin and Cellulose on Humus Formation

Successful Landfill Leachate Wastewater Treatment Using the Sequence of Ozonation, Adsorption on Charcoal and Photo-Ozonolysis

Evaluation of Commercial Humic Substances and Other Organic Amendments for the Immobilization of Copper Through 13C CPMAS NMR, FT-IR, and DSC Analyses

Contact Info

Product

Resources

About