Rodolfo Vignola | Università degli Studi "La Sapienza" di Roma (original) (raw)
Papers by Rodolfo Vignola
Studies in Surface Science and Catalysis, 2008
Abstract A full-scale pump&treat (p&t) and a demonstrative Permeable Reactive Bar... more Abstract A full-scale pump&treat (p&t) and a demonstrative Permeable Reactive Barrier (PRB) have been successfully working for two years in a gasoline station and for six months in a refinery, respectively. In both cases groundwater presented levels of methyl tertiary-...
<b>Copyright information:</b>Taken from "Characterization and performance of a t... more <b>Copyright information:</b>Taken from "Characterization and performance of a toluene-degrading biofilm developed on pumice stones"Microbial Cell Factories 2005;4():4-4.Published online 17 Jan 2005PMCID:PMC546200.Copyright © 2005 Di Lorenzo et al; licensee BioMed Central Ltd. , air filter; , feed tank; , air diffuser; , toluene tank; , peristaltic pump; , column 1; , column 2; , effluent tanks.
<b>Copyright information:</b>Taken from "Characterization and performance of a t... more <b>Copyright information:</b>Taken from "Characterization and performance of a toluene-degrading biofilm developed on pumice stones"Microbial Cell Factories 2005;4():4-4.Published online 17 Jan 2005PMCID:PMC546200.Copyright © 2005 Di Lorenzo et al; licensee BioMed Central Ltd. Before colonisation (A) pumice granules are blank. After 6 month of operation (B), rod shaped cells cover the pumice surface. In the 12 month biofilm, an abundant exopolymeric matrix is visible on pumice granules both at the bottom (C) and top (D) of the column.
La presente invention se rapporte a un procede de traitement d'eau contaminee par des metaux ... more La presente invention se rapporte a un procede de traitement d'eau contaminee par des metaux a haut degre d'oxydation, des composes aliphatiques, des composes aromatiques, des composes halogenes aromatiques, des composes alcanes et alcenes chlores ou des melanges de ces derniers. Ledit procede consiste a faire circuler l'eau contaminee a travers un systeme reactif constitue de fer metallique et d'une zeolite presentant un rapport silice/alumine superieur a 50, le fer et la zeolite etant places l'un derriere l'autre, et le premier element a travers lequel l'eau passe etant le fer.
An innovative system for the treatment of groundwater contaminated by different classes of organi... more An innovative system for the treatment of groundwater contaminated by different classes of organic pollutants is proposed: hydrocarbons, chlorinated compounds, such as 1,2 dichloroethane (1,2 DCA), or methyl-ter-butyl-ether (MtBE). The use of hydrophobic zeolites (HZ) overcomes the problems associated with the treatment of these compounds, whose remediation is very difficult by currently available technologies based on activated carbon (GAC) or zerovalent iron (ZVI). In fact, the selectivity of HZ is based on chemical-physic affinities of adsorbate to adsorbent. A wide range of pollutants related to oil industry activities has been examined: chlorinated ethanes, ethenes and benzenes, mono and polynuclear aromatic hydrocarbons. The results showed good to excellent sorption capacity and velocity. The complete remediation of two cases is demonstrated: the first is relative to groundwater containing aromatic hydrocarbons in the presence of MtBE, the second to groundwater contaminated by...
Archives of Environmental Protection, 2016
Three different types of Fe(II)-modified natural zeolites were tested as supports in continuous-f... more Three different types of Fe(II)-modified natural zeolites were tested as supports in continuous-flow columns for the treatment of Cr(VI) contaminated water. The natural zeolites chosen as support were commercially available Zeosand (80% clinoptilolite), ATZ (79% phillipsite/chabazite), and ZS-55RW (90% Chabazite). All the examined modified zeolites turned out active for hexavalent chromium abatement, lowering its concentration below the European regulation level, even at relatively high flow rates (40 mL/h, linear velocity 15 cm/h). Zeosand, having a broader pH range of stability, was found to be the best one in terms of both Fe(II) uptake (0.54 wt%) and Cr removal (90 mg Cr/Kg zeolite).
Plant Nutrition — Physiology and Applications, 1990
Pot trials were carried out to find the optimal inoculum conditions for an Azospirillum brasilens... more Pot trials were carried out to find the optimal inoculum conditions for an Azospirillum brasilense strain isolated from Italian soil. We examined different maize genotypes and increasing concentrations of Azospirillum (from 106 to 109 cells/plant); peat was used as a carrier, the formulation obtained being pre-tested for assaying microbial survival. The influence of two levels of nitrogen fertilizer was also evaluated. Efficiency of the peat formulation in root colonization was estimated by determining the number of viable cells inside the root at three different phases of plant growth. Two months after sowing both fresh and dry shoot weight were measured to evaluate the effects of inoculum on initial plant growth. Our results prove that peat formulation is a useful method for inoculating Azospirillum brasilense on maize. It is also shown that different maize genotypes have different growth responses although the number of microorganisms found inside the root can be comparable.
Microbial cell factories, Jan 17, 2005
BACKGROUND: Hydrocarbon-degrading biofilms in the treatment of contaminated groundwaters have rec... more BACKGROUND: Hydrocarbon-degrading biofilms in the treatment of contaminated groundwaters have received increasing attention due to the role played in the so-called "biobarriers". These are bioremediation systems in which a microbial consortium adherent to a solid support is placed across the flow of a contaminated plume, thus promoting biodegradation of the pollutant. RESULTS: A microbial consortium adherent to pumice granules (biofilm) developed from a toluene-enriched microflora in a mini-scale system, following continuous supply of a mineral medium containing toluene, over a 12-month period. Observation by scanning electron microscopy, together with quantification of the biomass attached to pumice, evidenced the presence of abundant exopolymeric material surrounding the cells in the biofilm. Toluene removal monitored during 12-month operation, reached 99%. Identification of the species, based on comparative 16S ribosomal DNA (rDNA) sequence analysis, revealed that Rhodo...
Microporous and Mesoporous Materials, 2015
In this paper, the use of a mesoporous silica alumina (MSA) for the removal of hydrocarbons from ... more In this paper, the use of a mesoporous silica alumina (MSA) for the removal of hydrocarbons from water is outlined. In particular, we focused our attention on the structural modifications that occur during the adsorption process using toluene and benzene as target contaminants and two different material shapes: particle and extruded. Different characterization techniques such as SEM, powder XRD, TGA and IR absorption are used to gain a deep investigation of MSA characteristics. Indeed, morphological features of MSA, the thermal behavior of the loaded and unloaded material including its regeneration and host-guest interactions were largely examined. SEM images and EDX analysis of the two materials have confirmed their amorphous nature and their elemental composition. Powder XRD patterns of as-synthesized (unloaded) and loaded MSA displayed the appearance of some reflection peaks after the adsorption of benzene and toluene. A Le Bail refinement indicated a monoclinic structure for these molecules when adsorbed onto the MSA. FT-IR measurement on loaded and unloaded MSA highlighted the interaction of water with the free silanol groups while the aromatic hydrocarbons probably adsorbed onto different active sites (Lewis acid sites). Indeed, intrinsic acidity measurements by pyridine adsorption showed the presence of a fairly good number of these acid sites. Finally, the thermal behavior of loaded MSA samples with different contaminants has shown the strong influence of water on the desorption temperature of pollutants from MSA.
E3S Web of Conferences, 2013
Despite of over 25 years of intensive technological efforts, sub-surface environment cleanup stil... more Despite of over 25 years of intensive technological efforts, sub-surface environment cleanup still remains a challenge, especially in case of highly contaminated sites. In this context, ion exchanger technologies could provide simple and effective solutions for heavy metal removal in water treatment. The challenge is finding exchanger able to operate in extreme natural environments or in situations involving natural interfering species such as inorganic ions. In this paper we exam the use of natural zeolites as versatile exchanger for environmental protection of coastal refinery's groundwater against pollution of Ni, Cd, Pb. The influence of particle diameter on clinoptilolite performances toward heavy metal removal is studied. Also, we evaluate the exchanger activities in condition of high ionic strength, commonly present in groundwater located under coastal petrol industries. The obtained results confirmed that ion exchangers could provide an effective solutions for remediation in complex environmental conditions.
Chemical Engineering Journal, 2011
Zeolite filters composed by ZSM-5 and Mordenite extrudated with 20 wt% of clay and alumina, respe... more Zeolite filters composed by ZSM-5 and Mordenite extrudated with 20 wt% of clay and alumina, respectively, were used in a long term tests of decontamination of groundwater containing a variety of hydrocarbons and significant concentrations of dissolved inorganic salts. Extensive physical-chemical characterization of the samples taken after 6 and 12 months of tests confirmed that zeolites did not undergo any modification, the original microporous volume being restored by thermal treatment. Deposition of gypsum and iron sulphide occurred without altering the sorption capacity of the adsorbents. The only macroscopic effect of the long permanence in groundwater was identified in the modification of the textural properties of the extrudates, with the increase of the mesopore volume, probably associated with the reconstruction of the binders due to the loss of Al in the case of ZSM-5 and to its deposition in Mordenite samples.
Microporous and Mesoporous Materials, 2013
Presently, World is facing water crisis due to fast industrial development and consequent huge qu... more Presently, World is facing water crisis due to fast industrial development and consequent huge quantity of noxious compounds discharged into water systems. According to this scenario, pollutant rejection from wastewater till environmentally acceptable levels has to be considered a global challenge. Opportunities from material science are described, providing an overview on zeolites and silico-aluminas as selective sorbents for water treatment. Expectations from zeolite membranes are described, as well. Inferred separation mechanisms and potential field of applications are discussed for each class of materials.
Microporous and Mesoporous Materials, 2012
We investigated the 1,2-dichloroethane (DCE) adsorption process into an organophilic zeolite mord... more We investigated the 1,2-dichloroethane (DCE) adsorption process into an organophilic zeolite mordenite. A combined diffractometric, thermogravimetric and gas chromatographic approach enabled to obtain clear evidence of DCE adsorption in mordenite channels as well as to pinpoint the exact location of the organic species found in the structure. Rietveld refinement revealed the incorporation of 2.5 DCE molecules and approximately 4 water molecules within the mordenite channel system, in very good agreement with the weight loss given by TG analysis and the saturation capacity determined by the adsorption isotherm. This relevant incorporation of DCE molecules caused a remarkable increase in the dimension of the 12-ring, when compared to the parent zeolite. The distances between the oxygen atoms of the water molecules from the chlorine atoms of the organic molecule (W-Cl1 = 2.34 Å, W-Cl2 = 2.53 Å) suggest that different DCE molecules could be connected by means of hydrogen bonds through water, to form a DCE and water molecule complex. The isotherm adsorption model for organic compounds from an aqueous dilute solution was selected based on the results of the structural investigation.
Procedure for treatment of water contaminated by apolar organic compounds and / or heavy metals w... more Procedure for treatment of water contaminated by apolar organic compounds and / or heavy metals which consists in circulating water through a system comprising at least two types of zeolites having a ratio of silica / alumina> 50, placed in succession wherein the first zeolite through which the water is passed is characterized by a high absorption capacity and dimensions including structural channel between 7 and 50 A, whereas the second is characterized by a high capacity for removal of molecules with a molecular diameter comparable with structural dimensions ranging channel 5 to 7 A.
Studies in Surface Science and Catalysis, 2008
Abstract A full-scale pump&treat (p&t) and a demonstrative Permeable Reactive Bar... more Abstract A full-scale pump&treat (p&t) and a demonstrative Permeable Reactive Barrier (PRB) have been successfully working for two years in a gasoline station and for six months in a refinery, respectively. In both cases groundwater presented levels of methyl tertiary-...
<b>Copyright information:</b>Taken from "Characterization and performance of a t... more <b>Copyright information:</b>Taken from "Characterization and performance of a toluene-degrading biofilm developed on pumice stones"Microbial Cell Factories 2005;4():4-4.Published online 17 Jan 2005PMCID:PMC546200.Copyright © 2005 Di Lorenzo et al; licensee BioMed Central Ltd. , air filter; , feed tank; , air diffuser; , toluene tank; , peristaltic pump; , column 1; , column 2; , effluent tanks.
<b>Copyright information:</b>Taken from "Characterization and performance of a t... more <b>Copyright information:</b>Taken from "Characterization and performance of a toluene-degrading biofilm developed on pumice stones"Microbial Cell Factories 2005;4():4-4.Published online 17 Jan 2005PMCID:PMC546200.Copyright © 2005 Di Lorenzo et al; licensee BioMed Central Ltd. Before colonisation (A) pumice granules are blank. After 6 month of operation (B), rod shaped cells cover the pumice surface. In the 12 month biofilm, an abundant exopolymeric matrix is visible on pumice granules both at the bottom (C) and top (D) of the column.
La presente invention se rapporte a un procede de traitement d'eau contaminee par des metaux ... more La presente invention se rapporte a un procede de traitement d'eau contaminee par des metaux a haut degre d'oxydation, des composes aliphatiques, des composes aromatiques, des composes halogenes aromatiques, des composes alcanes et alcenes chlores ou des melanges de ces derniers. Ledit procede consiste a faire circuler l'eau contaminee a travers un systeme reactif constitue de fer metallique et d'une zeolite presentant un rapport silice/alumine superieur a 50, le fer et la zeolite etant places l'un derriere l'autre, et le premier element a travers lequel l'eau passe etant le fer.
An innovative system for the treatment of groundwater contaminated by different classes of organi... more An innovative system for the treatment of groundwater contaminated by different classes of organic pollutants is proposed: hydrocarbons, chlorinated compounds, such as 1,2 dichloroethane (1,2 DCA), or methyl-ter-butyl-ether (MtBE). The use of hydrophobic zeolites (HZ) overcomes the problems associated with the treatment of these compounds, whose remediation is very difficult by currently available technologies based on activated carbon (GAC) or zerovalent iron (ZVI). In fact, the selectivity of HZ is based on chemical-physic affinities of adsorbate to adsorbent. A wide range of pollutants related to oil industry activities has been examined: chlorinated ethanes, ethenes and benzenes, mono and polynuclear aromatic hydrocarbons. The results showed good to excellent sorption capacity and velocity. The complete remediation of two cases is demonstrated: the first is relative to groundwater containing aromatic hydrocarbons in the presence of MtBE, the second to groundwater contaminated by...
Archives of Environmental Protection, 2016
Three different types of Fe(II)-modified natural zeolites were tested as supports in continuous-f... more Three different types of Fe(II)-modified natural zeolites were tested as supports in continuous-flow columns for the treatment of Cr(VI) contaminated water. The natural zeolites chosen as support were commercially available Zeosand (80% clinoptilolite), ATZ (79% phillipsite/chabazite), and ZS-55RW (90% Chabazite). All the examined modified zeolites turned out active for hexavalent chromium abatement, lowering its concentration below the European regulation level, even at relatively high flow rates (40 mL/h, linear velocity 15 cm/h). Zeosand, having a broader pH range of stability, was found to be the best one in terms of both Fe(II) uptake (0.54 wt%) and Cr removal (90 mg Cr/Kg zeolite).
Plant Nutrition — Physiology and Applications, 1990
Pot trials were carried out to find the optimal inoculum conditions for an Azospirillum brasilens... more Pot trials were carried out to find the optimal inoculum conditions for an Azospirillum brasilense strain isolated from Italian soil. We examined different maize genotypes and increasing concentrations of Azospirillum (from 106 to 109 cells/plant); peat was used as a carrier, the formulation obtained being pre-tested for assaying microbial survival. The influence of two levels of nitrogen fertilizer was also evaluated. Efficiency of the peat formulation in root colonization was estimated by determining the number of viable cells inside the root at three different phases of plant growth. Two months after sowing both fresh and dry shoot weight were measured to evaluate the effects of inoculum on initial plant growth. Our results prove that peat formulation is a useful method for inoculating Azospirillum brasilense on maize. It is also shown that different maize genotypes have different growth responses although the number of microorganisms found inside the root can be comparable.
Microbial cell factories, Jan 17, 2005
BACKGROUND: Hydrocarbon-degrading biofilms in the treatment of contaminated groundwaters have rec... more BACKGROUND: Hydrocarbon-degrading biofilms in the treatment of contaminated groundwaters have received increasing attention due to the role played in the so-called "biobarriers". These are bioremediation systems in which a microbial consortium adherent to a solid support is placed across the flow of a contaminated plume, thus promoting biodegradation of the pollutant. RESULTS: A microbial consortium adherent to pumice granules (biofilm) developed from a toluene-enriched microflora in a mini-scale system, following continuous supply of a mineral medium containing toluene, over a 12-month period. Observation by scanning electron microscopy, together with quantification of the biomass attached to pumice, evidenced the presence of abundant exopolymeric material surrounding the cells in the biofilm. Toluene removal monitored during 12-month operation, reached 99%. Identification of the species, based on comparative 16S ribosomal DNA (rDNA) sequence analysis, revealed that Rhodo...
Microporous and Mesoporous Materials, 2015
In this paper, the use of a mesoporous silica alumina (MSA) for the removal of hydrocarbons from ... more In this paper, the use of a mesoporous silica alumina (MSA) for the removal of hydrocarbons from water is outlined. In particular, we focused our attention on the structural modifications that occur during the adsorption process using toluene and benzene as target contaminants and two different material shapes: particle and extruded. Different characterization techniques such as SEM, powder XRD, TGA and IR absorption are used to gain a deep investigation of MSA characteristics. Indeed, morphological features of MSA, the thermal behavior of the loaded and unloaded material including its regeneration and host-guest interactions were largely examined. SEM images and EDX analysis of the two materials have confirmed their amorphous nature and their elemental composition. Powder XRD patterns of as-synthesized (unloaded) and loaded MSA displayed the appearance of some reflection peaks after the adsorption of benzene and toluene. A Le Bail refinement indicated a monoclinic structure for these molecules when adsorbed onto the MSA. FT-IR measurement on loaded and unloaded MSA highlighted the interaction of water with the free silanol groups while the aromatic hydrocarbons probably adsorbed onto different active sites (Lewis acid sites). Indeed, intrinsic acidity measurements by pyridine adsorption showed the presence of a fairly good number of these acid sites. Finally, the thermal behavior of loaded MSA samples with different contaminants has shown the strong influence of water on the desorption temperature of pollutants from MSA.
E3S Web of Conferences, 2013
Despite of over 25 years of intensive technological efforts, sub-surface environment cleanup stil... more Despite of over 25 years of intensive technological efforts, sub-surface environment cleanup still remains a challenge, especially in case of highly contaminated sites. In this context, ion exchanger technologies could provide simple and effective solutions for heavy metal removal in water treatment. The challenge is finding exchanger able to operate in extreme natural environments or in situations involving natural interfering species such as inorganic ions. In this paper we exam the use of natural zeolites as versatile exchanger for environmental protection of coastal refinery's groundwater against pollution of Ni, Cd, Pb. The influence of particle diameter on clinoptilolite performances toward heavy metal removal is studied. Also, we evaluate the exchanger activities in condition of high ionic strength, commonly present in groundwater located under coastal petrol industries. The obtained results confirmed that ion exchangers could provide an effective solutions for remediation in complex environmental conditions.
Chemical Engineering Journal, 2011
Zeolite filters composed by ZSM-5 and Mordenite extrudated with 20 wt% of clay and alumina, respe... more Zeolite filters composed by ZSM-5 and Mordenite extrudated with 20 wt% of clay and alumina, respectively, were used in a long term tests of decontamination of groundwater containing a variety of hydrocarbons and significant concentrations of dissolved inorganic salts. Extensive physical-chemical characterization of the samples taken after 6 and 12 months of tests confirmed that zeolites did not undergo any modification, the original microporous volume being restored by thermal treatment. Deposition of gypsum and iron sulphide occurred without altering the sorption capacity of the adsorbents. The only macroscopic effect of the long permanence in groundwater was identified in the modification of the textural properties of the extrudates, with the increase of the mesopore volume, probably associated with the reconstruction of the binders due to the loss of Al in the case of ZSM-5 and to its deposition in Mordenite samples.
Microporous and Mesoporous Materials, 2013
Presently, World is facing water crisis due to fast industrial development and consequent huge qu... more Presently, World is facing water crisis due to fast industrial development and consequent huge quantity of noxious compounds discharged into water systems. According to this scenario, pollutant rejection from wastewater till environmentally acceptable levels has to be considered a global challenge. Opportunities from material science are described, providing an overview on zeolites and silico-aluminas as selective sorbents for water treatment. Expectations from zeolite membranes are described, as well. Inferred separation mechanisms and potential field of applications are discussed for each class of materials.
Microporous and Mesoporous Materials, 2012
We investigated the 1,2-dichloroethane (DCE) adsorption process into an organophilic zeolite mord... more We investigated the 1,2-dichloroethane (DCE) adsorption process into an organophilic zeolite mordenite. A combined diffractometric, thermogravimetric and gas chromatographic approach enabled to obtain clear evidence of DCE adsorption in mordenite channels as well as to pinpoint the exact location of the organic species found in the structure. Rietveld refinement revealed the incorporation of 2.5 DCE molecules and approximately 4 water molecules within the mordenite channel system, in very good agreement with the weight loss given by TG analysis and the saturation capacity determined by the adsorption isotherm. This relevant incorporation of DCE molecules caused a remarkable increase in the dimension of the 12-ring, when compared to the parent zeolite. The distances between the oxygen atoms of the water molecules from the chlorine atoms of the organic molecule (W-Cl1 = 2.34 Å, W-Cl2 = 2.53 Å) suggest that different DCE molecules could be connected by means of hydrogen bonds through water, to form a DCE and water molecule complex. The isotherm adsorption model for organic compounds from an aqueous dilute solution was selected based on the results of the structural investigation.
Procedure for treatment of water contaminated by apolar organic compounds and / or heavy metals w... more Procedure for treatment of water contaminated by apolar organic compounds and / or heavy metals which consists in circulating water through a system comprising at least two types of zeolites having a ratio of silica / alumina> 50, placed in succession wherein the first zeolite through which the water is passed is characterized by a high absorption capacity and dimensions including structural channel between 7 and 50 A, whereas the second is characterized by a high capacity for removal of molecules with a molecular diameter comparable with structural dimensions ranging channel 5 to 7 A.