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Barghi, Hamidreza
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Publikasjoner (8 av 8) Visa alla publikasjoner
Barghi, H., Skrifvars, M. & Taherzadeh, M. J. (2014). Catalytic Synthesis of Bulk Hydrophilic Acetaldehyde-Modified Polyamide 46. Current Organic Synthesis, 11(6), 288-294
Åpne denne publikasjonen i ny fane eller vindu >>Catalytic Synthesis of Bulk Hydrophilic Acetaldehyde-Modified Polyamide 46
2014 (engelsk)Inngår i: Current Organic Synthesis, ISSN 1570-1794, E-ISSN 1875-6271, Vol. 11, nr 6, s. 288-294Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Hydrophilization of Polyamide 46 (PA46) via modification with acetaldehyde in continuous phase was studied. The chemical modification of PA 46 with acetaldehyde resulted in a water-swollen polymer with hydrophilic property. The polyamide 46 undergoes a nucleophilic addition with acetaldehyde in the presence of aluminum chloride as a catalyst. The extent of bulk hydroxyethylation using AlCl3 resulted in 95.65% modification counted as total N-hydroxyethylated polyamide 46. The modification resulted in improved hydrophilic properties, and a maximum surface free energy of 44.6 mJ/m2 was achieved after 3 h reaction, whereas the unmodified PA46 had a surface free energy of 11.2 mJ/m2. In addition, thermal properties of the polymers were studied using differential scanning calorimetry and thermogravimetric analyses. The functionalization leads to decrease in the crystallization energy from 88 J/g to 51 J/g, while the melting energy is changed from 110 J/g to 53 J/g. Furthermore, the thermal stability of the PA46 to pyrolysis was diminished after hydroxylation.

sted, utgiver, år, opplag, sider
Bentham Science Publishers Ltd., 2014
Emneord
Resource Recovery
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-1870 (URN)10.2174/1570179411310010003 (DOI)000340717600006 ()2320/13751 (Lokal ID)2320/13751 (Arkivnummer)2320/13751 (OAI)
Tilgjengelig fra: 2015-11-13 Laget: 2015-11-13 Sist oppdatert: 2017-12-01bibliografisk kontrollert
Barghi, H. (2014). Functionalization of Synthetic Polymers for Membrane Bioreactors. (Doctoral dissertation). Chalmers University of Technology
Åpne denne publikasjonen i ny fane eller vindu >>Functionalization of Synthetic Polymers for Membrane Bioreactors
2014 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Membrane bioreactors (MBRs) show great promise for productivity improvement and energy conservation in conventional bioprocesses for wastewater reclamation. In order to attain high productivity in a bioprocess, it is crucial to retain the microorganisms in the bioreactors by preventing wash out. This enables recycling of the microorganisms, and is consequently saving energy. The main feature of MBRs is their permeable membranes, acting as a limitative interface between the medium and the microorganisms. Permeation of nutrients and metabolites through the membranes is thus dependent on the membrane characteristics, i.e. porosity, hydrophilicity,and polarity. The present thesis introduces membranes for MBRs to be used in a continuous feeding process, designed in the form of robust, durable, and semi-hydrophilic films that constitute an effective barrier for the microorganisms, while permitting passage of nutrients and metabolites. Polyamide 46 (polytetramethylene adipamide), a robust synthetic polymer, holds the desired capabilities, with the exception of porosity and hydrophilicity. In order to achieve adequate porosity and hydrophilicity, bulk functionalization of polyamide 46 with different reagents was performed. These procedures changed the configuration from dense planar to spherical, resulting in increased porosity. Hydroxyethylation of the changed membranes increased the surface tension from 11.2 to 44.6 mJ/m2. The enhanced hydrophilicity of PA 46 resulted in high productivity of biogas formation in a compact MBR, due to diminished biofouling. Copolymerization of hydrophilized polyamide 46 with hydroxymethyl 3,4-ethylenedioxythiophene revealed electroconductivity and hydrophilic properties, adequate for use in MBRs. To find either the maximal pH stability or the surface charge of the membranes having undergone carboxymethylation, polarity and the isoelectric point (pI) of the treated membranes were studied by means of a Zeta analyzer. The hydroxylated PA 46 was finally employed in a multilayer membrane bioreactor and compared with hydrophobic polyamide and PVDF membranes. The resulting biogas production showed that the hydroxylated PA 46 membrane was, after 18 days without regeneration, fully comparable with PVDF membranes.

sted, utgiver, år, opplag, sider
Chalmers University of Technology, 2014
Serie
Skrifter från Högskolan i Borås, ISSN 0280-381X ; 48
Serie
Doctoral theses at Chalmers University of Technology, ISSN 0346-718X ; 3649
Emneord
Bioreactor, Functionalization, Hydrophilic, Membrane, Polyamide 46, Synthetic polymer, Resursåtervinning
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-3688 (URN)2320/13354 (Lokal ID)978-91-7385-968-4 (ISBN)2320/13354 (Arkivnummer)2320/13354 (OAI)
Tilgjengelig fra: 2015-12-04 Laget: 2015-12-04 Sist oppdatert: 2016-08-19bibliografisk kontrollert
Barghi, H. & Taherzadeh, M. J. (2013). Bulk Hydrophilic Functionalization of Polyamide 46. Google Patents WO2013058702 A1.
Åpne denne publikasjonen i ny fane eller vindu >>Bulk Hydrophilic Functionalization of Polyamide 46
2013 (engelsk)Patent (Annet (populærvitenskap, debatt, mm))
Abstract [en]

(EN)A modified polymer as result of a bulk functionalization of polyamide 46 (PA 46) is presented, as well as methods for synthesizing the modified polymer. This functionalization of PA 46 is performed to provide a homogenous semi-permeable polyamide 46 capable of different charges and different porosities with particles of nanoscale size in order to replace or improve other polyamide fibers used in the textile industry, filtering processes, selective sorption, controlled release devices, phase transfer catalysts, chromatography media, biocompatible capsules, artificial skins, organs, bone void repair as well as in cell bioreactors and incubators, dental impliments, medical devices, clothing, detectors, perfusion devices, in regenerative medicine, and fuel cells. (FR)Un polymère modifié comme résultat d'une fonctionnalisation en masse de polyamide 46 (PA 46) est présenté, ainsi que des procédés de synthèse du polymère modifié. Cette fonctionnalisation de PA 46 est effectuée pour fournir un polyamide 46 semi-perméable homogène apte à des différentes charges et de différentes porosités avec des particules d'une dimension à l'échelle nanométrique afin de remplacer ou d'améliorer d'autres fibres de polyamide utilisées dans l'industrie textile, les procédés de filtration, la sorption sélective, les dispositifs à libération entretenue, les catalyseurs de transfert de phase, les supports de chromatographie, les capsules biocompatibles, les peaux artificielles, les organes, la réparation de cavités osseuses ainsi que les bioréacteurs et incubateurs de cellules, les implants dentaires, les dispositifs médicaux, les vêtements, les détecteurs, les dispositif de perfusion, en médecine régénérative et dans les piles à combustible.

sted, utgiver, år, opplag, sider
Google Patents, 2013
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-3333 (URN)2320/13266 (Lokal ID)2320/13266 (Arkivnummer)2320/13266 (OAI)
Patent
WO2013058702 A1 (2013-04-25)
Merknad

Pub. No.: WO/2013/058702; International Application No.: PCT/SE2012/051109 ; Publication Date: 25.04.2013; International Filing Date: 17.10.2012

Tilgjengelig fra: 2015-11-25 Laget: 2015-11-25 Sist oppdatert: 2016-06-28bibliografisk kontrollert
Youngsukkasem, S., Barghi, H., Rakshit, S. K. & Taherzadeh, M. T. (2013). Rapid Biogas Production by Compact Multi-Layer Membrane Bioreactor: Efficiency of Synthetic Polymeric Membranesane Reactor for Rapid Biogas Production. Energies, 6(12), 6211-6224
Åpne denne publikasjonen i ny fane eller vindu >>Rapid Biogas Production by Compact Multi-Layer Membrane Bioreactor: Efficiency of Synthetic Polymeric Membranesane Reactor for Rapid Biogas Production
2013 (engelsk)Inngår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 6, nr 12, s. 6211-6224Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Entrapment of methane-producing microorganisms between semi-permeable synthetic membranes in a multi-layer membrane bioreactor (MMBR) was studied and compared to the digestion capacity of a free-cell digester, using a hydraulic retention time of one day and organic loading rates (OLR) of 3.08, 6.16, and 8.16 g COD/L·day. The reactor was designed to retain bacterial cells with uprising plug flow through a narrow tunnel between membrane layers, in order to acquire maximal mass transfer in a compact bioreactor. Membranes of hydrophobic polyamide 46 (PA) and hydroxyethylated polyamide 46 (HPA) as well as a commercial membrane of polyvinylidene fluoride (PVDF) were examined. While the bacteria in the free-cell digester were washed out, the membrane bioreactor succeeded in retaining them. Cross-flow of the liquid through the membrane surface and diffusion of the substrate through the membranes, using no extra driving force, allowed the bacteria to receive nutrients and to produce biogas. However, the choice of membrane type was crucial. Synthesized hydrophobic PA membrane was not effective for this purpose, producing 50–121 mL biogas/day, while developed HPA membrane and the reference PVDF were able to transfer the nutrients and metabolites while retaining the cells, producing 1102–1633 and 1016–1960 mL biogas/day, respectively.

sted, utgiver, år, opplag, sider
M D P I AG, 2013
Emneord
membrane bioreactor, biogas, synthetic membrane, methane, anaerobic digestion, polyamide, PVDF, cell entrapment, Resursåtervinning
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-1786 (URN)10.3390/en6126211 (DOI)000330290600005 ()2320/13264 (Lokal ID)2320/13264 (Arkivnummer)2320/13264 (OAI)
Tilgjengelig fra: 2015-11-13 Laget: 2015-11-13 Sist oppdatert: 2017-12-01bibliografisk kontrollert
Barghi, H. & Taherzadeh, M. (2013). Synthesis of an electroconductive membrane using poly(hydroxymethyl-3,4-ethylenedioxythiophene-co-tetramethylene-N-hydroxyethyl adipamide). Journal of Materials Chemistry C, 1(39), 6347-6354
Åpne denne publikasjonen i ny fane eller vindu >>Synthesis of an electroconductive membrane using poly(hydroxymethyl-3,4-ethylenedioxythiophene-co-tetramethylene-N-hydroxyethyl adipamide)
2013 (engelsk)Inngår i: Journal of Materials Chemistry C, ISSN 2050-7526, E-ISSN 2050-7534, Vol. 1, nr 39, s. 6347-6354Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Synthesis of a novel electroconductive membrane (ECM) was studied with the aim of producing an electroconductive membrane (ECM) with low electrical resistance and appropriate mechanical properties. The method was based on copolymerization of a highly electroconductive monomer (hydroxymethyl-3,4-ethylenedioxythiophene) with highly mechanical resistant hydrophilized polyamide 46 (polytetramethylene-N-hydroxyethyl adipamide). Due to the lack of hydroxyl groups, polyamide 46 does not have the tendency to take part in any chemical reactions, therefore prior to copolymerization, PA 46 was hydrophilized with acetaldehyde to create reactive sites, which allowed copolymerization to occur. At the final stage, a very thin layer, 566 nm conductive poly(hydroxymethyl-3,4-ethylenedioxythiophene) homopolymer was localised using in situ plasma polymerization in order to improve the electrical conductivity of the obtained copolymer. The result was an adherent, highly conductive, semi-hydrophilic and flexible ECM. The presence of hydroxyl groups in the final product led to improved hydrophilicity of the conductive membrane with a surface tension of 41 mJ m−2. The electrical resistance of PA 46 was dramatically reduced after copolymerization, to 202 in dry and 54 kΩ cm−2 in wet conditions; furthermore, after plasma treatment, this reduction continued to 105 in dry and 2 kΩ cm−2 in wet conditions. Other parameters such as flux flow, roughness, pore size, pore distribution, contact angle, surface energy and thermal stability of the ECM were also investigated.

sted, utgiver, år, opplag, sider
R S C Publications, 2013
Emneord
Resource Recovery
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-1652 (URN)10.1039/C3TC30932K (DOI)000324757400022 ()2320/12941 (Lokal ID)2320/12941 (Arkivnummer)2320/12941 (OAI)
Tilgjengelig fra: 2015-11-13 Laget: 2015-11-13 Sist oppdatert: 2017-12-01bibliografisk kontrollert
Barghi, H., Skrifvars, M. & Taherzadeh, M. J. (2011). Synthesis and characterization of novel bulk hydrophilic acetaldehyde modified polyamide 46. In: : . Paper presented at 14th IUPAC International Symposium on MacroMolecular Complexes, MMC-14, Helsinki. University of Helsinki
Åpne denne publikasjonen i ny fane eller vindu >>Synthesis and characterization of novel bulk hydrophilic acetaldehyde modified polyamide 46
2011 (engelsk)Konferansepaper, Poster (with or without abstract) (Annet vitenskapelig)
sted, utgiver, år, opplag, sider
University of Helsinki, 2011
Emneord
Biotechnology
HSV kategori
Forskningsprogram
Resursåtervinning
Identifikatorer
urn:nbn:se:hb:diva-6629 (URN)2320/9656 (Lokal ID)2320/9656 (Arkivnummer)2320/9656 (OAI)
Konferanse
14th IUPAC International Symposium on MacroMolecular Complexes, MMC-14, Helsinki
Tilgjengelig fra: 2015-12-22 Laget: 2015-12-22 Sist oppdatert: 2016-07-14bibliografisk kontrollert
Ylitervo, P., Barghi, H., Franzén, C. J. & Taherzadeh, M. J. (2010). Improving the stability and mechanical resistance of capsules for encapsulation of S. cerevisiae. In: : . Paper presented at International Workshop on wood biorefinery and tree biotechnology, Örnsköldsvik, June 21-23 2010.
Åpne denne publikasjonen i ny fane eller vindu >>Improving the stability and mechanical resistance of capsules for encapsulation of S. cerevisiae
2010 (engelsk)Konferansepaper, Poster (with or without abstract) (Annet vitenskapelig)
Abstract [en]

Nowadays, fuel ethanol is both used as a substitute and an additive to the conventional fossil fuels and the interest in converting lignocellulose to fuel ethanol has expanded in the last few decades. Lignocellulose is attractive as raw material due to its high abundance and low price. However, chemical hydrolysis or pre-treatment of lignocelluloses creates several components that are toxic to fermenting organisms and makes cultivation complicated. By using encapsulated yeast, one can overcome this problem. In encapsulation, the yeast cells are confined inside a capsule composed of an outer semi-permeable membrane and an inner liquid core (Fig. 1). Encapsulation is an attractive method since it can improve the cell stability and inhibitor tolerance, increase the biomass concentration, and decrease the cost of cell recovery, recycling, downstream processing, and fermentation time. Mechanical resistance is a key parameter together with permeability for the success of an encapsulation system. In order to improve the robustness of the capsules we are testing different cross linkers to introduce covalent bonds to the chitosan-alginate matrix. By treating chitosan covered alginate capsules with glutaraldehyde the capsules became harder and less elastic. One big disadvantage in using crosslinking agent is, however, that they are toxic for the yeast. If the encapsulated yeast is treated at too harsh conditions they will die. Although, to improve the capsules mechanical strength the membrane have to be crosslinked to a satisfying degree. We have examined different capsule-treatments and found some encouraging results when applying repetitive treatments with crosslinking agent.

Emneord
encapsulation, s.cerevisiae, bioethanol, Energi och material
HSV kategori
Identifikatorer
urn:nbn:se:hb:diva-6494 (URN)2320/7409 (Lokal ID)2320/7409 (Arkivnummer)2320/7409 (OAI)
Konferanse
International Workshop on wood biorefinery and tree biotechnology, Örnsköldsvik, June 21-23 2010
Tilgjengelig fra: 2015-12-22 Laget: 2015-12-22 Sist oppdatert: 2016-11-11bibliografisk kontrollert
Majdejabbari, S., Barghi, H. & Taherzadeh, M. J. (2010). Synthesis and Characterization of Biosuperabsorbent Based on Ovalbumin Protein. Journal of macromolecular science. Pure and applied chemistry (Print), 47(7), 708-715
Åpne denne publikasjonen i ny fane eller vindu >>Synthesis and Characterization of Biosuperabsorbent Based on Ovalbumin Protein
2010 (engelsk)Inngår i: Journal of macromolecular science. Pure and applied chemistry (Print), ISSN 1060-1325, E-ISSN 1520-5738, Vol. 47, nr 7, s. 708-715Artikkel i tidsskrift (Annet vitenskapelig) Published
Abstract [en]

A biosuperabsorbent (Bio-SAP) hydrogel from ovalbumin (egg protein) was synthesized via modification with an acylating reagent and a bifunctional crosslinker, and its swelling behavior was investigated. The protein was acylated using ethylenediaminetetraacetic dianhydride (EDTAD), and then crosslinked by glutaraldehyde and dried. Bio-SAP provided through this method includes modification of lysyl residues in the unfolded protein by adding one or more hydrophilic carboxyl groups to increase the hydrophilicity of protein. The water binding capacity was measured in deionized water, 0.9% NaCl solution and synthetic urine, which under the best conditions were 296, 64 and 56 g/g after 24 h, respectively. In addition, the effects of EDTAD/protein ratio on the chemical modification of the protein, the various chemical neutralization agents, pH sensitivity and ionic strength, as well as temperature and particle size on the water absorption capacity with and without load and its kinetic were also investigated.

Emneord
biosuperabsorbent, ovalbumin protein, chemical modification, crosslink, swelling, Energi och material
HSV kategori
Identifikatorer
urn:nbn:se:hb:diva-2807 (URN)10.1080/10601325.2010.483399 (DOI)2320/6572 (Lokal ID)2320/6572 (Arkivnummer)2320/6572 (OAI)
Tilgjengelig fra: 2015-11-13 Laget: 2015-11-13 Sist oppdatert: 2017-12-01bibliografisk kontrollert
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