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Phenol and its derivatives are hazardous, teratogenic and mutagenic, and have gained significant attention in recent years due to their high toxicity even at low concentrations. Phenolic compounds appear in petroleum refinery wastewater from several sources, such as the neutralized spent caustic waste streams, the tank water drain, the desalter effluent and the production unit. Therefore, effective treatments of such wastewaters are crucial. Conventional techniques used to treat these wastewaters pose several drawbacks, such as incomplete or low efficient removal of phenols. Recently, biocatalysts have attracted much attention for the sustainable and effective removal of toxic chemicals like phenols from wastewaters. The advantages of biocatalytic processes over the conventional treatment methods are their ability to operate over a wide range of operating conditions, low consumption of oxidants, simpler process control, and no delays or shock loading effects associated with the start-up/shutdown of the plant. Among different biocatalysts, oxidoreductases (i.e., tyrosinase, laccase and horseradish peroxidase) are known as green catalysts with massive potentialities to sustainably tackle phenolic contaminants of high concerns. Such enzymes mainly catalyze the o-hydroxylation of a broad spectrum of environmentally related contaminants into their corresponding o-diphenols. This review covers the latest advancement regarding the exploitation of these enzymes for sustainable oxidation of phenolic compounds in wastewater, and suggests a way forward.
Sanaz Salehi; Kourosh Abdollahi; Reza Panahi; Nejat Rahmanian; Mozaffar Shakeri; Babak Mokhtarani. Applications of Biocatalysts for Sustainable Oxidation of Phenolic Pollutants: A Review. Sustainability 2021, 13, 8620 .
AMA StyleSanaz Salehi, Kourosh Abdollahi, Reza Panahi, Nejat Rahmanian, Mozaffar Shakeri, Babak Mokhtarani. Applications of Biocatalysts for Sustainable Oxidation of Phenolic Pollutants: A Review. Sustainability. 2021; 13 (15):8620.
Chicago/Turabian StyleSanaz Salehi; Kourosh Abdollahi; Reza Panahi; Nejat Rahmanian; Mozaffar Shakeri; Babak Mokhtarani. 2021. "Applications of Biocatalysts for Sustainable Oxidation of Phenolic Pollutants: A Review." Sustainability 13, no. 15: 8620.
Deactivation is the major challenge of heteroatom‐substituted mesoporous silica materials for large scale applications. Here we report the impact of plugging of mesochannels of AlSBA‐15 on activity and stability of liquid‐phase acylation of anisole with (extremely) low catalyst loadings of 0.15‐0.6 wt.% and 0.6‐3 wt.% in batch and in repeated batch reactions, respectively. The analysis of property‐catalytic performances showed that deactivation of the plugged AlSBA‐15 was partially from a physical cause by deposition of a uniform nanometer layer of coke on the surface blocking the active sites which could be restored by calcination and partially from an irreversible chemical cause by Al leaching. The catalytic performance of plugged AlSBA‐15 was compared with that of open AlSBA‐15. The plugged AlSBA‐15 showed lower but more sustained activity than that by open AlSBA‐15 coming from less and different type of coke deposition. These properties of plugged AlSBA‐15 resulted in two times higher productivity (44.3 vs 23.3 mg‐product/mg‐catalyst) than that by open AlSBA‐15. The plugging of mesochannels thus reduced the amount of coke deposition and stabilized the catalyst; however, it exerted no effect on Al leaching. In conclusion, understanding the role of plugging of mesochannels in stabilization and Al leaching and coke deposition in deactivation are useful to design and synthesize efficient solid acid catalysts for liquid‐phase organic reactions.
Mozaffar Shakeri; Ali Shirzadeh Zarnagh. New Insights into the Deactivation and Stabilization Causes of Plugged AlSBA‐15 in Liquid‐phase Friedel‐Crafts Organic Reactions. ChemCatChem 2020, 12, 5439 -5448.
AMA StyleMozaffar Shakeri, Ali Shirzadeh Zarnagh. New Insights into the Deactivation and Stabilization Causes of Plugged AlSBA‐15 in Liquid‐phase Friedel‐Crafts Organic Reactions. ChemCatChem. 2020; 12 (21):5439-5448.
Chicago/Turabian StyleMozaffar Shakeri; Ali Shirzadeh Zarnagh. 2020. "New Insights into the Deactivation and Stabilization Causes of Plugged AlSBA‐15 in Liquid‐phase Friedel‐Crafts Organic Reactions." ChemCatChem 12, no. 21: 5439-5448.
Crystallization of as-mesocellular silica foam (as-MCF) into TS-1 zeolites by conventional hydrothermal and dense-gel routes is reported. The TS-1 synthesized through the dense-gel route (TS-1-d) showed higher meso-macroporosity (0.311 vs 0.233 cm3/g), smaller particle size (130 vs 305 nm), and enhanced external surface area (86 vs 31 m2/g) than that synthesized under conventional hydrothermal conditions (TS-1-h). These might suggest that an organic template from as-MCF acted as mesoporogen in the dense-gel synthesis; however, segregation of the organic template and the synthesis mixture occurred in the conventional hydrothermal synthesis. The obtained TS-1 from the crystallization of as-MCF showed an enhanced framework Ti. The turnover frequencies (h–1) of TS-1-d toward hydroxylation of phenol and oxidation of dibenzothiophene (DBT) were 2 and 5 times, respectively, higher than those by TS-1-h. The DBT conversion by TS-1-d reached >99.0%, while it was only 63% by TS-1-h, suggesting the potential of TS-1-d for deep desulfurization of the fuels. Consequently, the crystallization of as-mesoporous materials through the dense-gel route is a promising approach to prepare TS-1 zeolites with smaller particle sizes and enhanced mesoporosity.
Mozaffar Shakeri; Ali Shirzadeh Zarnagh. Crystallization of as-Mesocellular Silica Foam into Hierarchical TS-1 Zeolites by Conventional Hydrothermal and Dense-Gel Routes for Oxidation Reactions. ACS Omega 2020, 5, 9334 -9338.
AMA StyleMozaffar Shakeri, Ali Shirzadeh Zarnagh. Crystallization of as-Mesocellular Silica Foam into Hierarchical TS-1 Zeolites by Conventional Hydrothermal and Dense-Gel Routes for Oxidation Reactions. ACS Omega. 2020; 5 (16):9334-9338.
Chicago/Turabian StyleMozaffar Shakeri; Ali Shirzadeh Zarnagh. 2020. "Crystallization of as-Mesocellular Silica Foam into Hierarchical TS-1 Zeolites by Conventional Hydrothermal and Dense-Gel Routes for Oxidation Reactions." ACS Omega 5, no. 16: 9334-9338.
Simultaneous control over particle size and framework Ti content are the major challenges of synthesis of efficient TS-1 catalysts. Here we firstly report control over the particle size and framework Ti content of TS-1 catalysts in a wide range through conventional hydrothermal approach, evaluate catalytic performances of obtained TS-1 catalysts, and then rationally design a novel procedure of synthesis. The characterization of TS-1 catalysts by several techniques revealed that synthesis conditions through conventional hydrothermal approach to reach minimum particle size is different than that to reach maximum framework Ti content. The catalytic study of TS-1 catalysts showed that conversion of phenol (kinetic diameter of 0.57 nm) increased with increase in the particle size, reached a maximum of 29.9% for the TS-1 with particle size of 270 nm, and then dropped significantly for the TS-1 with biggest particle size. The conversion of dibenzothiophene (kinetic diameter of 0.9 nm), however, decreased with increase in the particle size and maximum conversion of 69.0% was achieved by the TS-1 with smallest particle size of 130 nm. No TS-1 catalyst synthesized through conventional approach was efficient in oxidation of the both substrates as the catalyst lacks either small particle size or enhanced framework Ti. Based on the property-function results from conventional synthesis, we rationally designed a novel synthesis of TS-1 with minimum water and optimum pH by (NH4)2CO3 addition to minimize the particle size and maximize framework Ti content, respectively. The resultant TS-1 with both features of small particle size of 185 nm and enhanced framework Ti resulted in full conversions of phenol and bulky substrate of dibenzothiophene and generates the least amount of wastewater. The new approach applied here is promising and applicable to make efficient Lewis-acid zeolites.
Mozaffar Shakeri; Safoura Bakhodaye Dehghanpour. Rational synthesis of TS-1 zeolite to direct both particle size and framework Ti in favor of enhanced catalytic performance. Microporous and Mesoporous Materials 2020, 298, 110066 .
AMA StyleMozaffar Shakeri, Safoura Bakhodaye Dehghanpour. Rational synthesis of TS-1 zeolite to direct both particle size and framework Ti in favor of enhanced catalytic performance. Microporous and Mesoporous Materials. 2020; 298 ():110066.
Chicago/Turabian StyleMozaffar Shakeri; Safoura Bakhodaye Dehghanpour. 2020. "Rational synthesis of TS-1 zeolite to direct both particle size and framework Ti in favor of enhanced catalytic performance." Microporous and Mesoporous Materials 298, no. : 110066.
Various silica precursors of tetraethyl orthosilicate (TEOS), mesocellular silica foam (MCF), and a combination of TEOS and MCF are investigated under solvent‐free conditions to achieve efficient TS‐1 catalyst. The obtained TS‐1 catalysts were characterized by powder XRD, FTIR, diffusive reflectance UV‐Vis, FE‐SEM, TEM, N2 sorption, DLS, and EDS. The TS‐1 synthesized by combination of TEOS and MCF possesses smaller crystal size, higher yield of solid materials, and enhanced Ti incorporation than that obtained by either only MCF or TEOS. The average particle size of TS‐1 catalysts synthesized by using MCF, TEOS, and the combination of TEOS and MCF were about 350, 170, and 105 nm, respectively. The yield of solid TS‐1 by using MCF, TEOS, and the combination of TEOS and MCF were 0.28, 0.80, and 1.20 g‐TS‐1/g‐TPAOH, respectively. Oxidation of 1000 ppm of the bulky substrate of dibenzothiophene (DBT; kinetic diameter 0.9 nm) by TS‐1 synthesized by combination of TEOS and MCF was about two times higher than that by the TS‐1 catalyst prepared either by TEOS or MCF. Furthermore, oxidation of 5000 ppm of DBT (equally to 5 separate batches) by this catalyst resulted in full conversion in 24 h. Consequently, the use of combination of TEOS and amorphous silica of MCF as silica precursor under solvent‐free conditions is a practical approach to prepare efficient TS‐1 catalyst.
Mozaffar Shakeri. Efficient Synthesis of Titaniosilicalite‐1 Zeolite Nanoparticles Under Solvent‐free Conditions for the Oxidation of Dibenzothiophene: Impact of Silica Precursor. ChemistrySelect 2019, 4, 7566 -7571.
AMA StyleMozaffar Shakeri. Efficient Synthesis of Titaniosilicalite‐1 Zeolite Nanoparticles Under Solvent‐free Conditions for the Oxidation of Dibenzothiophene: Impact of Silica Precursor. ChemistrySelect. 2019; 4 (25):7566-7571.
Chicago/Turabian StyleMozaffar Shakeri. 2019. "Efficient Synthesis of Titaniosilicalite‐1 Zeolite Nanoparticles Under Solvent‐free Conditions for the Oxidation of Dibenzothiophene: Impact of Silica Precursor." ChemistrySelect 4, no. 25: 7566-7571.
Crystal size and framework Ti content are two main factors which influence catalytic performances of TS‐1 catalysts. Control over the crystal size and framework Ti of TS‐1 through the synthesis of TS‐1 in the presence of polyethylene glycol (PEG) is reported. The crystal size of TS‐1 sample synthesized in the presence of PEG, TS‐1‐PEG was 230 nm. However, the size of TS‐1 synthesized without PEG, standard sample, was 290 nm. The TS‐1‐PEG possess higher amount of framework Ti content and less anatase TiO2 in comparison with TS‐1. The catalytic reaction tests showed superior activity of TS‐1‐PEG toward hydroxylation of phenol and oxidation of dibenzothiophene, deep desulfurization of fuels, as a result of cooperative effects of smaller particle size and higher framework Ti content. Consequently, using safe and un‐expensive PEG polymer is a powerful approach to synthesize TS‐1 with small crystal size and high framework Ti content to make efficient TS‐1 catalyst.
Mozaffar Shakeri; Safoura Bakhodaye Dehghanpour. Preparation of Efficient TS‐1 with Small Particle Size and Enhanced Framework Ti. ChemistrySelect 2019, 4, 4771 -4774.
AMA StyleMozaffar Shakeri, Safoura Bakhodaye Dehghanpour. Preparation of Efficient TS‐1 with Small Particle Size and Enhanced Framework Ti. ChemistrySelect. 2019; 4 (16):4771-4774.
Chicago/Turabian StyleMozaffar Shakeri; Safoura Bakhodaye Dehghanpour. 2019. "Preparation of Efficient TS‐1 with Small Particle Size and Enhanced Framework Ti." ChemistrySelect 4, no. 16: 4771-4774.
Solid catalysts which are heterogeneous at the macroscopic scale but homogeneous at the microscopic level were prepared by the encapsulation of Fe(salen) by a “ship in a bottle” approach.
Rafael L. Oliveira; Tom Nijholt; Mozaffar Shakeri; Petra E. De Jongh; Robertus J. M. Klein Gebbink; Krijn P. De Jong. Encapsulation of chiral Fe(salen) in mesoporous silica structures for use as catalysts to produce optically active sulfoxides. Catalysis Science & Technology 2016, 6, 5124 -5133.
AMA StyleRafael L. Oliveira, Tom Nijholt, Mozaffar Shakeri, Petra E. De Jongh, Robertus J. M. Klein Gebbink, Krijn P. De Jong. Encapsulation of chiral Fe(salen) in mesoporous silica structures for use as catalysts to produce optically active sulfoxides. Catalysis Science & Technology. 2016; 6 (13):5124-5133.
Chicago/Turabian StyleRafael L. Oliveira; Tom Nijholt; Mozaffar Shakeri; Petra E. De Jongh; Robertus J. M. Klein Gebbink; Krijn P. De Jong. 2016. "Encapsulation of chiral Fe(salen) in mesoporous silica structures for use as catalysts to produce optically active sulfoxides." Catalysis Science & Technology 6, no. 13: 5124-5133.
Rafael L. Oliveira; Mozaffar Shakeri; Johannes D. Meeldijk; Krijn P. De Jong; Petra E. De Jongh. Mapping nanocavities in plugged SBA-15 with confined silver nanostructures. Microporous and Mesoporous Materials 2015, 201, 234 -239.
AMA StyleRafael L. Oliveira, Mozaffar Shakeri, Johannes D. Meeldijk, Krijn P. De Jong, Petra E. De Jongh. Mapping nanocavities in plugged SBA-15 with confined silver nanostructures. Microporous and Mesoporous Materials. 2015; 201 ():234-239.
Chicago/Turabian StyleRafael L. Oliveira; Mozaffar Shakeri; Johannes D. Meeldijk; Krijn P. De Jong; Petra E. De Jongh. 2015. "Mapping nanocavities in plugged SBA-15 with confined silver nanostructures." Microporous and Mesoporous Materials 201, no. : 234-239.
Mozaffar Shakeri; Lucian Roiban; Vital Yazerski; Gonzalo Prieto; Robertus J. M. Klein Gebbink; Petra E. De Jongh; Krijn P. De Jong. Engineering and Sizing Nanoreactors To Confine Metal Complexes for Enhanced Catalytic Performance. ACS Catalysis 2014, 4, 3791 -3796.
AMA StyleMozaffar Shakeri, Lucian Roiban, Vital Yazerski, Gonzalo Prieto, Robertus J. M. Klein Gebbink, Petra E. De Jongh, Krijn P. De Jong. Engineering and Sizing Nanoreactors To Confine Metal Complexes for Enhanced Catalytic Performance. ACS Catalysis. 2014; 4 (10):3791-3796.
Chicago/Turabian StyleMozaffar Shakeri; Lucian Roiban; Vital Yazerski; Gonzalo Prieto; Robertus J. M. Klein Gebbink; Petra E. De Jongh; Krijn P. De Jong. 2014. "Engineering and Sizing Nanoreactors To Confine Metal Complexes for Enhanced Catalytic Performance." ACS Catalysis 4, no. 10: 3791-3796.
Metal nanoparticle growth represents a major deactivation mechanism of supported catalysts and other functional nanomaterials, particularly those based on low melting-point metals. Here we investigate the impact of the support porous structure on the stability of CuZnO/SiO2 model methanol synthesis catalysts. A series of silica materials with ordered cagelike (SBA-16 mesostructure) and disordered (SiO2-gel) porosities and varying pore sizes were employed as catalyst supports. Nitric oxide moderated nitrate decomposition enabled the synthesis of catalytically active Cu nanoparticles (3-5 nm) exclusively inside the silica pores with short interparticle spacings. Under relevant reactive conditions, confinement of the Cu particles in cagelike silica pores notably enhances catalyst stability by limiting Cu particle growth as compared to catalysts deposited in SiO2-gel host materials with also 3D and highly interconnected though unconstrained porosity. For both pore morphologies, we find a direct relationship between catalyst stability and support porosity, provided the narrowest characteristic pore dimension is employed as a porosity descriptor. For cagelike porosities this corresponds to the size of the entrances to the nanocages. Our results point to nanoparticle diffusion and coalescence as a relevant growth mechanism under reactive conditions and underscore the significance of the narrowest pore constrictions to mitigate growth and improve catalyst stability. This finding contributes to the establishment of general and quantitative structure-stability relationships which are essential for the design of catalysts and related functional nanostructures with long lifetimes under operation conditions.
Gonzalo Prieto; Mozaffar Shakeri; Krijn P. De Jong; Petra E. De Jongh. Quantitative Relationship between Support Porosity and the Stability of Pore-Confined Metal Nanoparticles Studied on CuZnO/SiO2 Methanol Synthesis Catalysts. ACS Nano 2014, 8, 2522 -2531.
AMA StyleGonzalo Prieto, Mozaffar Shakeri, Krijn P. De Jong, Petra E. De Jongh. Quantitative Relationship between Support Porosity and the Stability of Pore-Confined Metal Nanoparticles Studied on CuZnO/SiO2 Methanol Synthesis Catalysts. ACS Nano. 2014; 8 (3):2522-2531.
Chicago/Turabian StyleGonzalo Prieto; Mozaffar Shakeri; Krijn P. De Jong; Petra E. De Jongh. 2014. "Quantitative Relationship between Support Porosity and the Stability of Pore-Confined Metal Nanoparticles Studied on CuZnO/SiO2 Methanol Synthesis Catalysts." ACS Nano 8, no. 3: 2522-2531.
Karin Engström; Eric V. Johnston; Oscar Verho; Karl P. J. Gustafson; Mozaffar Shakeri; Cheuk-Wai Tai; Jan-E. Bäckvall. Co-immobilization of an Enzyme and a Metal into the Compartments of Mesoporous Silica for Cooperative Tandem Catalysis: An Artificial Metalloenzyme. Angewandte Chemie International Edition 2013, 52, 14006 -14010.
AMA StyleKarin Engström, Eric V. Johnston, Oscar Verho, Karl P. J. Gustafson, Mozaffar Shakeri, Cheuk-Wai Tai, Jan-E. Bäckvall. Co-immobilization of an Enzyme and a Metal into the Compartments of Mesoporous Silica for Cooperative Tandem Catalysis: An Artificial Metalloenzyme. Angewandte Chemie International Edition. 2013; 52 (52):14006-14010.
Chicago/Turabian StyleKarin Engström; Eric V. Johnston; Oscar Verho; Karl P. J. Gustafson; Mozaffar Shakeri; Cheuk-Wai Tai; Jan-E. Bäckvall. 2013. "Co-immobilization of an Enzyme and a Metal into the Compartments of Mesoporous Silica for Cooperative Tandem Catalysis: An Artificial Metalloenzyme." Angewandte Chemie International Edition 52, no. 52: 14006-14010.
Ship shape! Chiral (salen)CoIII complexes (spheres) inside plugged nanochannels of SBA‐15 materials is achieved using a ship‐in‐a‐bottle synthesis technique. The local concentration of the metal complexes and the catalytic activity (such as the hydrolytic kinetic resolution of 1,2‐epoxyalkanes; see scheme) showed a strong dependence on the size of the window.
Mozaffar Shakeri; Robertus J. M. Klein Gebbink; Petra E. De Jongh; Krijn P. De Jong. Tailoring the Window Sizes to Control the Local Concentration and Activity of (salen)Co Catalysts in Plugged Nanochannels of SBA-15 Materials. Angewandte Chemie International Edition 2013, 52, 10854 -10857.
AMA StyleMozaffar Shakeri, Robertus J. M. Klein Gebbink, Petra E. De Jongh, Krijn P. De Jong. Tailoring the Window Sizes to Control the Local Concentration and Activity of (salen)Co Catalysts in Plugged Nanochannels of SBA-15 Materials. Angewandte Chemie International Edition. 2013; 52 (41):10854-10857.
Chicago/Turabian StyleMozaffar Shakeri; Robertus J. M. Klein Gebbink; Petra E. De Jongh; Krijn P. De Jong. 2013. "Tailoring the Window Sizes to Control the Local Concentration and Activity of (salen)Co Catalysts in Plugged Nanochannels of SBA-15 Materials." Angewandte Chemie International Edition 52, no. 41: 10854-10857.
Plugged SBA-15 materials consist of mesoporous channels constricted along the central axis by windows. Tailoring and measurement of physical properties, particularly the window sizes, of plugged SBA-15 materials are crucial for potential host–guest applications. In this paper we report a synthesis procedure over a wider range of conditions (temperature and time of synthesis) for tailoring the physical properties of plugged SBA-15 materials and then assess the window sizes for the first time. The plugged SBA-15 materials showed rod-like morphology of 1–3 μm in length. The formation of plugged SBA-15 materials was confirmed by X-ray diffraction and N2 physisorption. Each of the plugged SBA-15 materials was modified by a series of alkoxysilanes with increasing alkyl chain length, and the window size was estimated from the shortest alkyl chain length blocking N2 adsorption. The window sizes were approximately 2.3, 2.6 and 3.0 nm for plugged SBA-15 synthesized at 70, 80, or 90 °C for 1 day, respectively and those were 3.1 and 3.9 nm for plugged SBA-15 synthesized at 70 and 80 °C for 3 days. The results showed that increase in the temperature at synthesis time of 1 day enhanced both the pore and window sizes, whereas extended synthesis time enhanced the window sizes predominantly. The found trend is that plugged SBA-15 materials lost plugging at extended synthesis times and higher temperatures. Overall, the procedures described here now make it possible to rationally design and synthesize plugged SBA-15 materials for host–guest applications in different fields.
Mozaffar Shakeri; Robertus J.M. Klein Gebbink; Petra E. de Jongh; Krijn P. de Jong. Control and assessment of plugging of mesopores in SBA-15 materials. Microporous and Mesoporous Materials 2012, 170, 340 -345.
AMA StyleMozaffar Shakeri, Robertus J.M. Klein Gebbink, Petra E. de Jongh, Krijn P. de Jong. Control and assessment of plugging of mesopores in SBA-15 materials. Microporous and Mesoporous Materials. 2012; 170 ():340-345.
Chicago/Turabian StyleMozaffar Shakeri; Robertus J.M. Klein Gebbink; Petra E. de Jongh; Krijn P. de Jong. 2012. "Control and assessment of plugging of mesopores in SBA-15 materials." Microporous and Mesoporous Materials 170, no. : 340-345.
Eric V. Johnston; Oscar Verho; Markus D. Kärkäs; Mozaffar Shakeri; Cheuk-Wai Tai; Pål Palmgren; Kristofer Eriksson; Sven Oscarsson; Jan-E. Bäckvall. Highly Dispersed Palladium Nanoparticles on Mesocellular Foam: An Efficient and Recyclable Heterogeneous Catalyst for Alcohol Oxidation. Chemistry – A European Journal 2012, 18, 12202 -12206.
AMA StyleEric V. Johnston, Oscar Verho, Markus D. Kärkäs, Mozaffar Shakeri, Cheuk-Wai Tai, Pål Palmgren, Kristofer Eriksson, Sven Oscarsson, Jan-E. Bäckvall. Highly Dispersed Palladium Nanoparticles on Mesocellular Foam: An Efficient and Recyclable Heterogeneous Catalyst for Alcohol Oxidation. Chemistry – A European Journal. 2012; 18 (39):12202-12206.
Chicago/Turabian StyleEric V. Johnston; Oscar Verho; Markus D. Kärkäs; Mozaffar Shakeri; Cheuk-Wai Tai; Pål Palmgren; Kristofer Eriksson; Sven Oscarsson; Jan-E. Bäckvall. 2012. "Highly Dispersed Palladium Nanoparticles on Mesocellular Foam: An Efficient and Recyclable Heterogeneous Catalyst for Alcohol Oxidation." Chemistry – A European Journal 18, no. 39: 12202-12206.
An integrated process for the chiral separation of the industrially relevant substance 2′,6′-pipecoloxylidide (PPX), an intermediate in the manufacture of a number of anesthetics, was developed. By combining three different techniques, chromatography, crystallization, and racemization, high productivity was achieved. All unit operations were executed using a common solvent system, full recycling, and a minimum of solvent exchanges or removals. The target molecule was obtained with an enantiopurity of >99.5 wt %.
Jan von Langermann; Malte Kaspereit; Mozaffar Shakeri; Heike Lorenz; Martin Hedberg; Matthew J. Jones; Kerstin Larson; Björn Herschend; Robert Arnell; Erik Temmel; Jan-Erling Bäckvall; Achim Kienle; Andreas Seidel-Morgenstern. Design of an Integrated Process of Chromatography, Crystallization and Racemization for the Resolution of 2′,6′-Pipecoloxylidide (PPX). Organic Process Research & Development 2012, 16, 343 -352.
AMA StyleJan von Langermann, Malte Kaspereit, Mozaffar Shakeri, Heike Lorenz, Martin Hedberg, Matthew J. Jones, Kerstin Larson, Björn Herschend, Robert Arnell, Erik Temmel, Jan-Erling Bäckvall, Achim Kienle, Andreas Seidel-Morgenstern. Design of an Integrated Process of Chromatography, Crystallization and Racemization for the Resolution of 2′,6′-Pipecoloxylidide (PPX). Organic Process Research & Development. 2012; 16 (2):343-352.
Chicago/Turabian StyleJan von Langermann; Malte Kaspereit; Mozaffar Shakeri; Heike Lorenz; Martin Hedberg; Matthew J. Jones; Kerstin Larson; Björn Herschend; Robert Arnell; Erik Temmel; Jan-Erling Bäckvall; Achim Kienle; Andreas Seidel-Morgenstern. 2012. "Design of an Integrated Process of Chromatography, Crystallization and Racemization for the Resolution of 2′,6′-Pipecoloxylidide (PPX)." Organic Process Research & Development 16, no. 2: 343-352.
Highly dispersed palladium nanoparticles (1–2 nm) supported in large‐pore mesocellular foam (MCF; 29 nm) were synthesized. The Pd‐nanocatalyst/MCF system was characterized by transmission electron microscopy (TEM), powder X‐ray diffraction (XRD) and X‐ray photoelectron spectroscopy (XPS). The performance of the Pd nanocatalyst obtained was examined for amine racemization. The Pd nanocatalyst showed higher activity and selectivity toward racemization of (S)‐1‐phenylethyl amine than any other amine racemization catalyst reported so far and it could be reused several times. Our data from TEM and XRD suggest a restructuring of the Pd nanocatalyst from amorphous to crystalline and an increase in Pd nanocatalyst size during the racemization reaction. This led to an unexpected increase of activity after the first use. The Pd nanocatalyst obtained can be integrated with other resolving processes of racemic organic compounds to increase the yield of chiral organic products.
Mozaffar Shakeri; Cheuk-Wai Tai; Emmanuelle Göthelid; Sven Oscarsson; Jan-E. Bäckvall. Small Pd Nanoparticles Supported in Large Pores of Mesocellular Foam: An Excellent Catalyst for Racemization of Amines. Chemistry – A European Journal 2011, 17, 13269 -13273.
AMA StyleMozaffar Shakeri, Cheuk-Wai Tai, Emmanuelle Göthelid, Sven Oscarsson, Jan-E. Bäckvall. Small Pd Nanoparticles Supported in Large Pores of Mesocellular Foam: An Excellent Catalyst for Racemization of Amines. Chemistry – A European Journal. 2011; 17 (47):13269-13273.
Chicago/Turabian StyleMozaffar Shakeri; Cheuk-Wai Tai; Emmanuelle Göthelid; Sven Oscarsson; Jan-E. Bäckvall. 2011. "Small Pd Nanoparticles Supported in Large Pores of Mesocellular Foam: An Excellent Catalyst for Racemization of Amines." Chemistry – A European Journal 17, no. 47: 13269-13273.
Karin Engström; Mozaffar Shakeri; Jan-E. Bäckvall. Dynamic Kinetic Resolution of ?-Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A. European Journal of Organic Chemistry 2011, 2011, 1827 -1830.
AMA StyleKarin Engström, Mozaffar Shakeri, Jan-E. Bäckvall. Dynamic Kinetic Resolution of ?-Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A. European Journal of Organic Chemistry. 2011; 2011 (10):1827-1830.
Chicago/Turabian StyleKarin Engström; Mozaffar Shakeri; Jan-E. Bäckvall. 2011. "Dynamic Kinetic Resolution of ?-Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A." European Journal of Organic Chemistry 2011, no. 10: 1827-1830.
Candida antarctica lipase A (CALA) immobilized in functionalized mesocellular foam in the presence of sucrose, followed by lyophilization, led to a dramatic increase in the enantioselectivity as well as an improved thermostability of the enzyme. The immobilized lipase was used for kinetic resolution (KR) and dynamic kinetic resolution (DKR) of the β‐amino ester, ethyl 3‐amino‐3‐phenylpropanoate. The temperature of optimum activity of CALA shifted from 20–30 °C to 80–90 °C on immobilization in the MCF. An “enantiomeric ratio” E (E=νA/νB; νA and νB are the rate constants for entantiomers A and B) of 69 and a conversion of 43 % in 1 h were obtained at 80 °C, whereas non‐immobilized CALA lost its activity at T≥50 °C. The obtained immobilized CALA showed an E value of greater than 500 at 22 °C. Combination of the immobilized CALA with a ruthenium complex, acting as a racemization catalyst, allowed for a successful DKR of ethyl 3‐amino‐3‐phenylpropanoate resulting in 85 % conversion and 89 % ee.
Mozaffar Shakeri; Karin Engström; Anders G. Sandström; Jan-E. Bäckvall. Highly Enantioselective Resolution of β-Amino Esters by Candida antarctica Lipase A Immobilized in Mesocellular Foam: Application to Dynamic Kinetic Resolution. ChemCatChem 2010, 2, 534 -538.
AMA StyleMozaffar Shakeri, Karin Engström, Anders G. Sandström, Jan-E. Bäckvall. Highly Enantioselective Resolution of β-Amino Esters by Candida antarctica Lipase A Immobilized in Mesocellular Foam: Application to Dynamic Kinetic Resolution. ChemCatChem. 2010; 2 (5):534-538.
Chicago/Turabian StyleMozaffar Shakeri; Karin Engström; Anders G. Sandström; Jan-E. Bäckvall. 2010. "Highly Enantioselective Resolution of β-Amino Esters by Candida antarctica Lipase A Immobilized in Mesocellular Foam: Application to Dynamic Kinetic Resolution." ChemCatChem 2, no. 5: 534-538.
A recombinant dye-decolorizing peroxidase (rDyP) produced from Aspergillus oryzae was immobilized in synthesized silica-based mesocellular foam (MCF: average pore size 25 nm) and used for decolorization of the anthraquinone dye, Remazol Brilliant Blue R (RBBR). The adsorption yields of rDyP immobilized in MCF increased as the pH decreased from 6 to 3. However, the activity yields of the immobilized rDyP decreased with decreasing pH. The overall efficiency, defined as adsorption yield × activity yield, reached its maximum of 83% at pH 5. In repeated dye-decolorization tests, 20 batches of RBBR could be decolorized by the MCF-immobilized rDyP. MCF showed significantly better performance for rDyP immobilization in term of retaining enzyme activity and dye-decolorization ability compared to previous studies using other mesoporous materials.
Mozaffar Shakeri; Makoto Shoda. Efficient decolorization of an anthraquinone dye by recombinant dye-decolorizing peroxidase (rDyP) immobilized in silica-based mesocellular foam. Journal of Molecular Catalysis B: Enzymatic 2010, 62, 277 -281.
AMA StyleMozaffar Shakeri, Makoto Shoda. Efficient decolorization of an anthraquinone dye by recombinant dye-decolorizing peroxidase (rDyP) immobilized in silica-based mesocellular foam. Journal of Molecular Catalysis B: Enzymatic. 2010; 62 (3-4):277-281.
Chicago/Turabian StyleMozaffar Shakeri; Makoto Shoda. 2010. "Efficient decolorization of an anthraquinone dye by recombinant dye-decolorizing peroxidase (rDyP) immobilized in silica-based mesocellular foam." Journal of Molecular Catalysis B: Enzymatic 62, no. 3-4: 277-281.
We examined the activity of free Rhizopus oryzae lipase (ROL) and ROL immobilized on mesoporous materials in transesterification reactions in various dialkylimidazolium-cation based ionic liquids. For free ROL, the highest activity (0.39 U/mg protein) was obtained in [OMIm][PF6] followed by that (0.28 U/mg protein) in [BMIm][PF6]. Specific activities of ROL immobilized on mesocellular foam (MCF) were only 0.47 and 0.43 U/mg protein in [OMIm][PF6] and [BMIm][PF6], respectively. However, the specific activities of ROL immobilized on octadecyl functionalized MCF (C18-MCF) increased significantly to 15.64 and 14.84 U/mg protein in [OMIm][PF6] and [BMIm][PF6], respectively. Consequently, ROL immobilized on C18-MCF is a promising biocatalyst for biotransformation reactions in ionic liquids.
Mozaffar Shakeri; Koei Kawakami. Significant changes in the transesterification activity of free and mesoporous-immobilized Rhizopus oryzae lipase in ionic liquids. Journal of Biotechnology 2010, 145, 281 -283.
AMA StyleMozaffar Shakeri, Koei Kawakami. Significant changes in the transesterification activity of free and mesoporous-immobilized Rhizopus oryzae lipase in ionic liquids. Journal of Biotechnology. 2010; 145 (3):281-283.
Chicago/Turabian StyleMozaffar Shakeri; Koei Kawakami. 2010. "Significant changes in the transesterification activity of free and mesoporous-immobilized Rhizopus oryzae lipase in ionic liquids." Journal of Biotechnology 145, no. 3: 281-283.