This article describes a modification of the conventional membrane crystallization technique in w... more This article describes a modification of the conventional membrane crystallization technique in which a membrane is used to dose the solvent/antisolvent composition to generate supersaturation and induce crystallization in a drug solution. Two operative configurations are proposed: (a) solvent/antisolvent demixing crystallization, where the solvent is removed in at higher flow rate than the antisolvent so that phase inversion promotes supersaturation and (b) antisolvent addition, in which the antisolvent is dosed into the crystallizing drug solution. In both cases, solvent/antisolvent migration occurs in vapor phase and it is controlled by the porous membrane structure, acting on the operative process parameters. This mechanism is different than that observed when forcing the liquid phases through the pores and the more finely controllable supersaturated environment would generate crystals with the desired characteristics. Two organic molecules of relevant industrial implication, like paracetamol and glycine, were used to test the new systems. Experiments demonstrated that, by using antisolvent membrane crystallization in both configurations, accurate control of solution composition at the crystallization point has been achieved with effects on crystals morphology.
... Gianluca Di Profio*a, Valentina Grossoa, Antonella Caridic, Rocco Caliandrob, Antonietta Guag... more ... Gianluca Di Profio*a, Valentina Grossoa, Antonella Caridic, Rocco Caliandrob, Antonietta Guagliardib, Giuseppe Chitab, Efrem Curcioc and ... E-mail: g.diprofio@itm.cnr.it; Fax: +390984402103; Tel: +390984492010. b Institute of Crystallography (IC-CNR), Via G. Amendola ...
Critical Review in Biotechnology, Informa Publication
Abstract Biocatalytic membrane reactors have been widely used in different industries including f... more Abstract Biocatalytic membrane reactors have been widely used in different industries including food, fine chemicals, biological, biomedical, pharmaceuticals, environmental treatment and so on. This article gives an overview of the different immobilized enzymatic processes and their advantages over the conventional chemical catalysts. The application of a membrane bioreactor (MBR) reduces the energy consumption, and system size, in line with process intensification. The performances of MBR are considerably influenced by substrate concentration, immobilized matrix material, types of immobilization and the type of reactor. Advantages of a membrane associated bioreactor over a free-enzyme biochemical reaction, and a packed bed reactor are, large surface area of immobilization matrix, reuse of enzymes, better product recovery along with heterogeneous reactions, and continuous operation of the reactor. The present research work highlights immobilization techniques, reactor setup, enzyme stability under immobilized conditions, the hydrodynamics of MBR, and its application, particularly, in the field of sugar, starch, drinks, milk, pharmaceutical industries and energy generation.
Hybrid fluoropolymeric membranes with 25% loading of the fluorous-tagged (RfN)4W10O32 effect the ... more Hybrid fluoropolymeric membranes with 25% loading of the fluorous-tagged (RfN)4W10O32 effect the solvent-free photooxygenation of benzylic C-H bonds with up to 6100 TONs in 4 hours.
In this work, the ruthenium porphyrin complex Ru(4-(CF3)TPP)CO (1) (TPP=dianion of tetraphenylpor... more In this work, the ruthenium porphyrin complex Ru(4-(CF3)TPP)CO (1) (TPP=dianion of tetraphenylporphyrin) was entrapped into polymeric membranes during the phase inversion process to obtain new heterogeneous catalysts for aziridination reactions. In order to study the effect of the polymeric environment on the activity of the metallic complex, symmetric dense polymeric catalytic membranes were prepared using three different polymers: polyethersulphone (PES), polysulphone (PSf) and Hyflon AD60X. Different hydrophobicity/hydrophilicity characteristics, sorption properties and ability to retain the metallic complex characterized the catalytic polymeric membranes. On the basis of the good results compared to the other two polymers, Hyflon AD60X was selected to prepare asymmetric membranes with a skin layer on an open sublayer. The Hyflon AD60X membranes showed good catalytic activity in the aziridination reaction of α-methylstyrene by aryl azides and moreover they have been recycled without any loss in azide conversion and aziridine selectivity.
Two enzyme membrane reactors (EMR),(i) with one substrate (olive oil) in an oil-in-water emulsion... more Two enzyme membrane reactors (EMR),(i) with one substrate (olive oil) in an oil-in-water emulsion (E-EMR) and (ii) with two separated liquid phases (oil and water)(TSLP-EMR), have been studied for the conversion of the triglycerides to fatty acids and glycerol. The ...
Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and s... more Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and stability of SLM's are described. A flat sheet polypropylene membrane was used in all the experiments. The ions on which the SLM's were tested were Cr(III), Cr(VI), and Cd(II). The carriers were dinonyl-naphthalene sulfonic acid (DNNSA), Aliquat 336, and Alamine 336. The diluents were o-xylene, kerosene,
Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and s... more Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and stability of SLM's are described. A flat sheet polypropylene membrane was used in all the experiments. The ions on which the SLM's were tested were Cr(III), Cr(VI), and Cd(II). The carriers were dinonyl-naphthalene sulfonic acid (DNNSA), Aliquat 336, and Alamine 336. The diluents were o-xylene, kerosene,
Membrane operations such as ultrafiltration, nanofiltration and reverse osmosis, properly integra... more Membrane operations such as ultrafiltration, nanofiltration and reverse osmosis, properly integrated among them and/or with other conventional separation processes, have proven to be clean chemical processes. The study of a tanning process showed that many operations can be improved integrating them with membrane operations. The steps studied in this work were: enzymatic skins unhairing, degreasing of pickled sheepskins and chromium
Some experimental aspects on separation, concentration and purification of amino acids through su... more Some experimental aspects on separation, concentration and purification of amino acids through supported liquid membranes, by using - -phenylalanine as a model, are described. The liquid-liquid extraction experiments, the influence on he mass-transport phenomena of ...
... Catalysis Today Volume 75, Issues 1-4, 3 July 2002, Pages 77-85. ... 4: these contrasting asp... more ... Catalysis Today Volume 75, Issues 1-4, 3 July 2002, Pages 77-85. ... 4: these contrasting aspects can generate in some cases a difficulty to couple photocatalysis and membrane ... possibility to use sunlight makes this hybrid process promising in industrial and environmental fields. ...
Use of pressure-driven membrane processes integrated with conventional precipitation/dissolution ... more Use of pressure-driven membrane processes integrated with conventional precipitation/dissolution operations is described in order to reduce chromium content in waste water from the tanning process and simultaneously improve the quality of the recycled chromium by means of elimination/reduction of organic lipolytic components, metals and other impurities that accompany the chromium recovered by traditional processes. The results obtained in the identification
This article describes a modification of the conventional membrane crystallization technique in w... more This article describes a modification of the conventional membrane crystallization technique in which a membrane is used to dose the solvent/antisolvent composition to generate supersaturation and induce crystallization in a drug solution. Two operative configurations are proposed: (a) solvent/antisolvent demixing crystallization, where the solvent is removed in at higher flow rate than the antisolvent so that phase inversion promotes supersaturation and (b) antisolvent addition, in which the antisolvent is dosed into the crystallizing drug solution. In both cases, solvent/antisolvent migration occurs in vapor phase and it is controlled by the porous membrane structure, acting on the operative process parameters. This mechanism is different than that observed when forcing the liquid phases through the pores and the more finely controllable supersaturated environment would generate crystals with the desired characteristics. Two organic molecules of relevant industrial implication, like paracetamol and glycine, were used to test the new systems. Experiments demonstrated that, by using antisolvent membrane crystallization in both configurations, accurate control of solution composition at the crystallization point has been achieved with effects on crystals morphology.
... Gianluca Di Profio*a, Valentina Grossoa, Antonella Caridic, Rocco Caliandrob, Antonietta Guag... more ... Gianluca Di Profio*a, Valentina Grossoa, Antonella Caridic, Rocco Caliandrob, Antonietta Guagliardib, Giuseppe Chitab, Efrem Curcioc and ... E-mail: g.diprofio@itm.cnr.it; Fax: +390984402103; Tel: +390984492010. b Institute of Crystallography (IC-CNR), Via G. Amendola ...
Critical Review in Biotechnology, Informa Publication
Abstract Biocatalytic membrane reactors have been widely used in different industries including f... more Abstract Biocatalytic membrane reactors have been widely used in different industries including food, fine chemicals, biological, biomedical, pharmaceuticals, environmental treatment and so on. This article gives an overview of the different immobilized enzymatic processes and their advantages over the conventional chemical catalysts. The application of a membrane bioreactor (MBR) reduces the energy consumption, and system size, in line with process intensification. The performances of MBR are considerably influenced by substrate concentration, immobilized matrix material, types of immobilization and the type of reactor. Advantages of a membrane associated bioreactor over a free-enzyme biochemical reaction, and a packed bed reactor are, large surface area of immobilization matrix, reuse of enzymes, better product recovery along with heterogeneous reactions, and continuous operation of the reactor. The present research work highlights immobilization techniques, reactor setup, enzyme stability under immobilized conditions, the hydrodynamics of MBR, and its application, particularly, in the field of sugar, starch, drinks, milk, pharmaceutical industries and energy generation.
Hybrid fluoropolymeric membranes with 25% loading of the fluorous-tagged (RfN)4W10O32 effect the ... more Hybrid fluoropolymeric membranes with 25% loading of the fluorous-tagged (RfN)4W10O32 effect the solvent-free photooxygenation of benzylic C-H bonds with up to 6100 TONs in 4 hours.
In this work, the ruthenium porphyrin complex Ru(4-(CF3)TPP)CO (1) (TPP=dianion of tetraphenylpor... more In this work, the ruthenium porphyrin complex Ru(4-(CF3)TPP)CO (1) (TPP=dianion of tetraphenylporphyrin) was entrapped into polymeric membranes during the phase inversion process to obtain new heterogeneous catalysts for aziridination reactions. In order to study the effect of the polymeric environment on the activity of the metallic complex, symmetric dense polymeric catalytic membranes were prepared using three different polymers: polyethersulphone (PES), polysulphone (PSf) and Hyflon AD60X. Different hydrophobicity/hydrophilicity characteristics, sorption properties and ability to retain the metallic complex characterized the catalytic polymeric membranes. On the basis of the good results compared to the other two polymers, Hyflon AD60X was selected to prepare asymmetric membranes with a skin layer on an open sublayer. The Hyflon AD60X membranes showed good catalytic activity in the aziridination reaction of α-methylstyrene by aryl azides and moreover they have been recycled without any loss in azide conversion and aziridine selectivity.
Two enzyme membrane reactors (EMR),(i) with one substrate (olive oil) in an oil-in-water emulsion... more Two enzyme membrane reactors (EMR),(i) with one substrate (olive oil) in an oil-in-water emulsion (E-EMR) and (ii) with two separated liquid phases (oil and water)(TSLP-EMR), have been studied for the conversion of the triglycerides to fatty acids and glycerol. The ...
Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and s... more Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and stability of SLM's are described. A flat sheet polypropylene membrane was used in all the experiments. The ions on which the SLM's were tested were Cr(III), Cr(VI), and Cd(II). The carriers were dinonyl-naphthalene sulfonic acid (DNNSA), Aliquat 336, and Alamine 336. The diluents were o-xylene, kerosene,
Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and s... more Some results obtained with the aim of optimizing the permeation fluxes, separation factors, and stability of SLM's are described. A flat sheet polypropylene membrane was used in all the experiments. The ions on which the SLM's were tested were Cr(III), Cr(VI), and Cd(II). The carriers were dinonyl-naphthalene sulfonic acid (DNNSA), Aliquat 336, and Alamine 336. The diluents were o-xylene, kerosene,
Membrane operations such as ultrafiltration, nanofiltration and reverse osmosis, properly integra... more Membrane operations such as ultrafiltration, nanofiltration and reverse osmosis, properly integrated among them and/or with other conventional separation processes, have proven to be clean chemical processes. The study of a tanning process showed that many operations can be improved integrating them with membrane operations. The steps studied in this work were: enzymatic skins unhairing, degreasing of pickled sheepskins and chromium
Some experimental aspects on separation, concentration and purification of amino acids through su... more Some experimental aspects on separation, concentration and purification of amino acids through supported liquid membranes, by using - -phenylalanine as a model, are described. The liquid-liquid extraction experiments, the influence on he mass-transport phenomena of ...
... Catalysis Today Volume 75, Issues 1-4, 3 July 2002, Pages 77-85. ... 4: these contrasting asp... more ... Catalysis Today Volume 75, Issues 1-4, 3 July 2002, Pages 77-85. ... 4: these contrasting aspects can generate in some cases a difficulty to couple photocatalysis and membrane ... possibility to use sunlight makes this hybrid process promising in industrial and environmental fields. ...
Use of pressure-driven membrane processes integrated with conventional precipitation/dissolution ... more Use of pressure-driven membrane processes integrated with conventional precipitation/dissolution operations is described in order to reduce chromium content in waste water from the tanning process and simultaneously improve the quality of the recycled chromium by means of elimination/reduction of organic lipolytic components, metals and other impurities that accompany the chromium recovered by traditional processes. The results obtained in the identification
Uploads
Papers by Enrico Drioli