The Experts below are selected from a list of 1905 Experts worldwide ranked by ideXlab platform
Enrico Sanjust - One of the best experts on this subject based on the ideXlab platform.
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degradation of textile dyes using immobilized lignin peroxidase like metalloporphines under mild experimental conditions
Chemistry Central Journal, 2012Co-Authors: Paolo Zucca, Antonio Rescigno, Manuela Pintus, Andrea C Rinaldi, Enrico SanjustAbstract:Synthetic dyes represent a broad and heterogeneous class of durable pollutants, that are released in large amounts by the textile industry. The ability of two immobilized metalloporphines (structurally emulating the ligninolytic peroxidases) to bleach six chosen dyes (alizarin red S, phenosafranine, xylenol orange, methylene blue, methyl green, and methyl orange) was compared to enzymatic Catalysts. To achieve a green and sustainable process, very mild conditions were chosen. IPS/MnTSPP was the most promising Biomimetic Catalyst as it was able to effectively and quickly bleach all tested dyes. Biomimetic catalysis was fully characterized: maximum activity was centered at neutral pH, in the absence of any organic solvent, using hydrogen peroxide as the oxidant. The immobilized metalloporphine kept a large part of its activity during multi-cycle use; however, well-known redox mediators were not able to increase its catalytic activity. IPS/MnTSPP was also more promising for use in industrial applications than its enzymatic counterparts (lignin peroxidase, laccase, manganese peroxidase, and horseradish peroxidase). On the whole, the conditions were very mild (standard pressure, room temperature and neutral pH, using no organic solvents, and the most environmental-friendly oxidant) and a significant bleaching and partial mineralization of the dyes was achieved in approximately 1 h. Therefore, the process was consistent with large-scale applications. The Biomimetic Catalyst also had more promising features than the enzymatic Catalysts.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported. © 2007 Elsevier B.V. All rights reserved.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:Abstract In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported.
Paolo Zucca - One of the best experts on this subject based on the ideXlab platform.
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degradation of textile dyes using immobilized lignin peroxidase like metalloporphines under mild experimental conditions
Chemistry Central Journal, 2012Co-Authors: Paolo Zucca, Antonio Rescigno, Manuela Pintus, Andrea C Rinaldi, Enrico SanjustAbstract:Synthetic dyes represent a broad and heterogeneous class of durable pollutants, that are released in large amounts by the textile industry. The ability of two immobilized metalloporphines (structurally emulating the ligninolytic peroxidases) to bleach six chosen dyes (alizarin red S, phenosafranine, xylenol orange, methylene blue, methyl green, and methyl orange) was compared to enzymatic Catalysts. To achieve a green and sustainable process, very mild conditions were chosen. IPS/MnTSPP was the most promising Biomimetic Catalyst as it was able to effectively and quickly bleach all tested dyes. Biomimetic catalysis was fully characterized: maximum activity was centered at neutral pH, in the absence of any organic solvent, using hydrogen peroxide as the oxidant. The immobilized metalloporphine kept a large part of its activity during multi-cycle use; however, well-known redox mediators were not able to increase its catalytic activity. IPS/MnTSPP was also more promising for use in industrial applications than its enzymatic counterparts (lignin peroxidase, laccase, manganese peroxidase, and horseradish peroxidase). On the whole, the conditions were very mild (standard pressure, room temperature and neutral pH, using no organic solvents, and the most environmental-friendly oxidant) and a significant bleaching and partial mineralization of the dyes was achieved in approximately 1 h. Therefore, the process was consistent with large-scale applications. The Biomimetic Catalyst also had more promising features than the enzymatic Catalysts.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported. © 2007 Elsevier B.V. All rights reserved.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:Abstract In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported.
Antonio Rescigno - One of the best experts on this subject based on the ideXlab platform.
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degradation of textile dyes using immobilized lignin peroxidase like metalloporphines under mild experimental conditions
Chemistry Central Journal, 2012Co-Authors: Paolo Zucca, Antonio Rescigno, Manuela Pintus, Andrea C Rinaldi, Enrico SanjustAbstract:Synthetic dyes represent a broad and heterogeneous class of durable pollutants, that are released in large amounts by the textile industry. The ability of two immobilized metalloporphines (structurally emulating the ligninolytic peroxidases) to bleach six chosen dyes (alizarin red S, phenosafranine, xylenol orange, methylene blue, methyl green, and methyl orange) was compared to enzymatic Catalysts. To achieve a green and sustainable process, very mild conditions were chosen. IPS/MnTSPP was the most promising Biomimetic Catalyst as it was able to effectively and quickly bleach all tested dyes. Biomimetic catalysis was fully characterized: maximum activity was centered at neutral pH, in the absence of any organic solvent, using hydrogen peroxide as the oxidant. The immobilized metalloporphine kept a large part of its activity during multi-cycle use; however, well-known redox mediators were not able to increase its catalytic activity. IPS/MnTSPP was also more promising for use in industrial applications than its enzymatic counterparts (lignin peroxidase, laccase, manganese peroxidase, and horseradish peroxidase). On the whole, the conditions were very mild (standard pressure, room temperature and neutral pH, using no organic solvents, and the most environmental-friendly oxidant) and a significant bleaching and partial mineralization of the dyes was achieved in approximately 1 h. Therefore, the process was consistent with large-scale applications. The Biomimetic Catalyst also had more promising features than the enzymatic Catalysts.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported. © 2007 Elsevier B.V. All rights reserved.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:Abstract In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported.
Alessandro Piccolo - One of the best experts on this subject based on the ideXlab platform.
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Effects of field managements for soil organic matter stabilization on water-stable aggregate distribution and aggregate stability in three agricultural soils
Journal of Geochemical Exploration, 2013Co-Authors: Riccardo Spaccini, Alessandro PiccoloAbstract:Abstract The effect of different soil organic matter (SOM) managements on soil aggregate stability was evaluated in three agricultural sites in Italy. The field plots were treated with traditional deep tillage, minimum tillage, green manuring, mature compost, and iron-porphyrin as a Biomimetic Catalyst. Although the original soil texture exerted a strong influence on the overall soil physical quality, after 3 years of field experiments, the soil additions with humified compost, under maize cropping, improved both, the yield of water stable macroaggregates and the soil aggregate stability, with a pronounced effect on the aggregate distribution of the coarse textured soil. Soil treatments with the Biomimetic Catalyst, under wheat cropping, promoted an initial stable incorporation of finer particle-sizes in water-stable macro-aggregates. This effect was progressively lost with increasing experimental time due to either loss or inactivation of the Catalyst. Innovative management practices for SOM stabilization based on soil amendment of either humified mature compost or a water-soluble Catalyst to promote in-situ photopolymerization of humic molecules, were found to improve distribution and stability of soil water stable aggregates, as compared to the conventional methods of SOM management.
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Enhanced catechol oxidation by heterogeneous Biomimetic Catalysts immobilized on clay minerals
Journal of Molecular Catalysis A: Chemical, 2013Co-Authors: Assunta Nuzzo, Alessandro PiccoloAbstract:Abstract Two novel heterogeneous Biomimetic Catalysts were synthesized by immobilizing a meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate of manganese (III) chloride on both kaolinite and montmorillonite clay minerals, previously functionalized with a molecular spacer whose terminal nitrogen atom coordinates the metal in the porphyrin ring. The clay functionalization by a 3-(1-imidazolyl)propylcarbamoyl-3′-aminopropyl-triethoxysilane spacer was proved by X-ray diffraction, elemental analysis, DRIFT-IR, 13C- and 29Si-CPMAS-NMR spectroscopies, and the percent of manganese–porphyrin immobilized by the spacer coordination calculated by spectrophotometry. The activity of the novel Catalysts was evaluated in the oxidative coupling reaction of catechol, a humic phenol, using H2O2 as oxygen donor. The rate of catechol oxidation catalyzed by both heterogeneous Catalysts was about four times as fast as that catalyzed by the free manganese–porphyrin, and depended on the amount of Catalyst immobilized on clay minerals. Moreover, the activity of the heterogeneous Catalysts remained effective for at least two sequential reaction cycles, although at a decreasing rate. We showed that the immobilization of a Biomimetic Catalyst on clay minerals increased the catalytic efficiency and allowed the Catalyst recycling and reuse for additional reactions. Metal–porphyrins immobilized on clay minerals through a flexible spacer may act as environment-friendly heterogeneous Catalysts to control phenolic molecules in environmental humus.
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carbon sequestration in soils by hydrophobic protection and in situ catalyzed photo polymerization of soil organic matter som chemical and physical chemical aspects of som in field plots
2012Co-Authors: Riccardo Spaccini, Alessandro PiccoloAbstract:The application of innovative practices of soil organic matter (SOM) management, based on either soil amendment with hydropohobic mature compost or with a water-soluble Biomimetic Catalyst, has shown to enhance organic carbon sequestration in agricultural soils. In three different agricultural sites in Italy, field plots under maize were treated with traditional deep tillage, minimum tillage, green manuring and mature compost, whereas field plots under wheat were added with the iron–porphyrin Catalyst. In terms of soil physical quality, mature compost additions improved soil aggregate stability by favoring the increase of water-stable macroaggregates. After 3 years of field experiments, both minimum tillage and green manuring treatments confirmed short-term and even negative effects on organic carbon (OC) accumulation, as compared to traditional tillage. Conversely, the hydrophobic protection exerted by compost amendments on SOM successfully fixed OC in soil from 3 to 22 ton ha−1 more than for traditional tillage, depending on the experimental site. Solid-state CPMAS-NMR spectra of humic substances (HS) extracted from treated soils allowed the molecular characterization of the stable organic matter pool. NMR data combined with chemometric methods revealed that compost-added soils progressively incorporated aliphatic and aromatic hydrophobic components into soil humic fractions over the experimental period. Though more variable among experimental sites, the treatment with Biomimetic Catalyst positively affected both total soil organic carbon (SOC) content and molecular characteristics of humic extracts. An increased aromaticity and hydrophobicity was shown in the spectra of HS from soils treated with the Biomimetic Catalyst, thus suggesting an effective photo-polymerization of soil aromatic components and their progressive inclusion into the humic pool. In the first and second year of treaments with the water-soluble iron–porphyrin Catalyst, the in situ catalyzed photo-polymerization of SOM effectively occurred since soils were found to have sequestered from 4 to 24 ton ha−1 more than the control.
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Reduction of 2,4-dichlorophenol toxicity to Pseudomonas putida after oxidative incubation with humic substances and a Biomimetic Catalyst.
Ecotoxicology and environmental safety, 2006Co-Authors: Dittmar Hahn, A. Cozzolino, Alessandro Piccolo, Piero M. ArmenanteAbstract:Abstract The effect of a synthetic iron(III)-porphyrin meso-tetra(2,6-dichloro-3-sulfonatophenyl)porphyrinate as a Biomimetic Catalyst in the oxidative treatment of 2,4-dichlorophenol (2,4-DCP) with humic substances and H2O2 was evaluated in factorial design experiments conducted at different concentrations of 2,4-DCP (0–25 ppm) and different incubation treatment times (0, 24, 96, or 120 h). In the absence of this treatment, bioassays with the bacterium Pseudomonas putida (ATCC11250) showed decreasing specific growth rates μ (used here to quantify 2,4-DCP toxicity) with increasing concentrations of 2,4-DCP. However, when 2,4-DCP was treated as mentioned above the toxicity of the resulting 2,4-DCP solution was reduced significantly. At low 2,4-DCP concentrations (up to 5 ppm) and long incubation periods (as long as 120 h), the specific growth rate μ was comparable to that of cultures grown in the absence of 2,4-DCP. The reduction in toxicity was directly correlated to a decrease in the concentration of 2,4-DCP in the treated solutions, as measured by high-performance liquid chromatography. The reduced concentrations of 2,4-DCP in the treated solutions could be correctly predicted based on the relationship between the specific growth rates and the 2,4-DCP concentrations in untreated solutions. These results indicate that the oxidative coupling of 2,4-DCP to humic substances catalyzed by the synthetic iron(III)-porphyrin Catalyst in the presence of H2O2 is responsible for the removal of 2,4-DCP from solutions. This approach appears to be a promising alternative treatment to reduce 2,4-DCP bioavailability and thus toxicity in the environment.
Giuseppe Mocci - One of the best experts on this subject based on the ideXlab platform.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported. © 2007 Elsevier B.V. All rights reserved.
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5 10 15 20 tetrakis 4 sulfonato phenyl porphine mn iii immobilized on imidazole activated silica as a novel lignin peroxidase like Biomimetic Catalyst
Journal of Molecular Catalysis A-chemical, 2007Co-Authors: Paolo Zucca, Antonio Rescigno, Giuseppe Mocci, Enrico SanjustAbstract:Abstract In this study a new Biomimetic lignin-peroxidase-like Catalyst was investigated. Such a heterogeneous Catalyst could be of potential interest for oxidative degradation of plant effluents, containing soluble lignin derivatives. 5,10,15,20-Tetrakis(4-sulfonato-phenyl)porphine-Mn(III) was coordinated to imidazole-bearing silica to give a stable adduct; by contrast, the metalloporphine did not significantly interact with plain silica gel or aminopropylsilica. The adduct showed a remarkable ability to catalyze veratryl alcohol oxidation at the expenses of H2O2. Kinetic and operational characterisation of the Catalyst is also reported.