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Influence of reduction time of copper based catalysts: Cu/Al2O3and CuCr2O4on hydrogenolysis of glycerol

100%
Wołosiak-Hnat A., Milchert E., Lewandowski G., Grzmil B.
Polish Journal of Chemical Technology
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2011
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vol. 13
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issue 4
71-76
EN
High activity of copper based catalysts for C-O bond hydro-dehydrogenation and their poor activity for C-C bond cleavage1 have prompted an attempt to apply such catalysts in the hydrogenolysis of glycerol to 1,2- and 1,3-propanediol. In the present study the influence of hydrogen reduction time of the Cu/Al2O3 and CuCr2O4 copper catalysts on glycerol conversion and selectivity of transformation to propanediols and by-products was studied. At first a general comparison was made between the commercial catalysts and those prepared by the co-precipitation method. As better results were obtained in the presence of catalysts prepared by co-precipitation, they were selected for further detailed studies of the influence of reduction time. For both prepared catalysts Cu/Al2O3 and CuCr2O4 the reduction time of 8 h was optimal. In the presence of Cu/Al2O3 catalyst the conversion of glycerol was 59.0%, selectivity of transformation to 1,2-propanediol 77.4% and selectivity to 1,3-propanediol 1.9%. In the presence of CuCr2O4 the glycerol conversion was 30.3% and selectivity to 1,2-propanediol 67.3%.
2
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Glycerol steam reforming over ceria-zirconia supported metallic catalysts

88%
Cichy M.
Annales Universitatis Mariae Curie-Skłodowska, sectio AA – Chemia
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2019
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vol. 74
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issue 1
EN
Glycerol is a main by-product of transesterification reaction of plants oils to its methyl esters which are used as a substitute or as an additive to diesel fuel. Still growing so-called biodiesel production leads to large amounts of glycerol fraction flooding the market. One of the possible ways of its utilization is steam reforming reaction which main product is synthesis gas containing high concentration of hydrogen for which is still growing demand. In this work four metallic (Ni, Pt, Ru and Re) catalysts supported on ceria-zirconia mixed oxides have been investigated in glycerol steam reforming reaction.
3
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Lactic acid and hydrogen from glycerol via acceptorless dehydrogenation using homogeneous catalysts

88%
Bottari G., Barta K.
Recyclable Catalysis
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2015
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vol. 2
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issue 1
EN
Acceptorless dehydrogenation of alcohols has emerged as a powerful methodology for the valorization of biomass derived platform chemicals and building blocks. In this review we provide a short overview of the advantages and possible product outcomes of this method. The main focus will be devoted to the conversion of glycerol, which is the major waste product of biodiesel production, to lactic acid. While extensive research addresses the development of heterogeneous catalysts, recently new and highly active iridium and ruthenium complexes have also been reported. These novel homogeneous catalysts are even more active than the already reported heterogeneous systems and enable the direct conversion of glycerol into lactic acid and molecular hydrogen. While the product hydrogen might be used either as fuel or as reducing agent for other processes, lactic acid is a platform chemical widely employed by the polymer, pharmaceutical and food industries. The used catalytic methodology is atom-economic, waste-free and is uniquely suited for the efficient conversion of renewable resources.
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Separation of 1,3-Propanediol from Aqueous Solutions by Ion Exchange Chromatography

88%
Rukowicz B., Miesiąc I., Alejski K.
Polish Journal of Chemical Technology
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2014
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vol. 16
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issue 2
82-86
EN
1,3-propanediol is a promising monomer with many applications and can be produced by bioconversion of renewable resources. The separation of this product from fermentation broth is a difficult task. In this work, the application of cation exchange resin for the separation of 1,3-propanediol from model aqueous solution was examined. The best effect of separation of 1,3-propanediol from glycerol using sorption method was obtained for H+ resin form, although the observed partition coefficient of 1,3-propanediol was low. On the basis of the results of the sorption of 1,3-propanediol, the ionic forms of the resin were selected and used in the next experiments (H+, Ca2+, Ag+, Na+, Pb2+, Zn2+). The best results in ion exchange chromatography were obtained for cation exchange resin in H+ and Ca2+ form. The use of smaller particle size of resin and a longer length of the column allows to obtain better separation of mixtures.
5
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Effects of centrifugal stress on cell disruption and glycerol leakage fromDunaliella salina

75%
Xu Y., Milledge J. J., Abubakar A., Swamy R. A. R., Bailey D., Harvey P. J.
Microalgae Biotechnology
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2015
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vol. 1
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issue 1
EN
Dunaliella salina accumulates large amounts of intracellular glycerol in response to the increases in salt concentration, thus is a potential source for producing fuel grade glycerol as an alternative to biodiesel-derived crude glycerol. D. salina lacks a cell wall; therefore the mode of harvesting Dunaliella cells is critical to avoid cell disruption caused by extreme engineering conditions. This study explored cell disruption and glycerol leakage of D. salina under various centrifugal stresses during cell harvesting. Results show a centrifugal g-force lower than 5000 g caused little cell disruption, while a g-force higher than 9000 g led to ~40% loss of the intact cells and glycerol yields from the recovered algal pellets. Theoretical calculations of the centrifugal stresses that could rupture Dunaliella cells were in agreement with the experimental results, indicating optimisation of centrifugation conditions is important for recovering intact cells of D. salina enriched in glycerol.
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ASSESSMENT OF PHARMACEUTICAL PROPERTIES OF GYNAECOLOGICAL HYDROPHILIC GELS CONTAINING LACTIC ACID COMPLEXED WITH CHITOSAN

75%
Małolepsza-Jarmołowska K.
Progress on Chemistry and Application of Chitin and its Derivatives
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2012
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vol. 17
117 - 124
EN
Gels containing lactic acid complexed with chitosan at a stoichiometric ration 1:1 and 2:1 and 5-25% content of polyoxyethylene glycol 200 are able to move from 25 to 30 cm. The addition of glycerol increases the movability gels containing lactic acid complexed with chitosan in a stoichiometric ration 1:1 from 23 cm to 26 cm and at 2:1 ratio from 25 cm to 29 cm. Gels with addition 20-25% poloxamer 407 containing lactic acid complexed with chitosan and 5-25% content of glycerol reveal pH from 4.25 to 4.98 for 1:1 and from 3.60 to 4.45 for 2:1. The investigations showed that the addition of a thermosensitive polymer increases the adhesive properties of the investigated gels, but at the same time it increases their pH. The addition of glycerol or 1,2-propylene glycol reduces the pH and maintains high adhesion. The use of hydrofilizing substances allowed to obtain physiological range pH gynaecological gels.
7
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Biotechnological conversion of glycerol from biofuels to 1,3-propanediol using Escherichia coli

75%
Przystałowska H., Lipiński D., Słomski R.
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issue 1
23-34
EN
In the face of shortage of fossil fuel supplies and climate warming triggered by excessive carbon dioxide emission, alternative resources for chemical industry have gained considerable attention. Renewable resources and their derivatives are of particular interest. Glycerol, which constitutes one of the by-products during biodiesel production, is such a substrate. Thus, generated excess glycerol may become an environmental problem, since it cannot be disposed of in the environment. The most promising products obtained from glycerol are polyols, including 1,3-propanediol, an important substrate in the production of synthetic materials, e.g. polyurethanes, unsaturated polyesters, and epoxy resins. Glycerol can be used as a carbon and energy source for microbial growth in industrial microbiology to produce 1,3-propanediol. This paper is a review of metabolic pathways of native producers and E. coli with the acquired ability to produce the diol via genetic manipulations. Culture conditions during 1,3-PDO production and genetic modifications of E. coli used in order to increase efficiency of glycerol bioconversion are also described in this paper.
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PHARMACEUTICAL ASSESSMENT OF THERMOSENSITIVE HYDROPHILIC GELS WITH POLYVINYL PYRROLIDONE K-30 CONTAINING LACTIC ACID COMPLEXED WITH CHITOSAN

75%
Małolepsza-Jarmołowska K.
|
EN
Gels containing lactic acid complexed with chitosan at a stoichiometric ration 1:1 and 2:1 and 5-25% content of polyoxyethylene glycol 200 are able to move from 25 to 30 cm. Measurements performed in a biopharmaceutical model revealed that the addition of 20% poloxamer 407 to gels containing lactic acid complexed with chitosan in a stoichiometric ration 1:1 decreases their movability from 20 to 25 cm and at 2:1 ratio, from 22 to 28 cm. Higher concentrations of the poloxamer 407: 23 and 25% result in the movability of 20 to 24 cm. The addition of 5% PVP K-30 besides 1,2-propylene glycol increases the movability gels containing lactic acid complexed with chitosan in a stoichiometric ration 1:1 from 24 cm to 28 cm and at 2:1 ratio from 26 cm to 30 cm. Higher concentrations of the poloxamer 407: 23 and 25% result in the movability of 24 to 27 cm
9
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1,3-propanediol production by Escherichia coli expressing genes of dha operon from Clostridium butyricum 2CR371.5

75%
Dąbrowski S., Pietrewicz-Kubicz D., Zabłotna E., Długołęcka A.
Acta Biochimica Polonica
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2012
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vol. 59
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issue 3
357-361
EN
1,3-propanediol is used as a monomer in the production of some polymers e.g. polytrimethylene terephthalate used in the production of carpets and textile fibers and in the thermoplastics engineering. However, the traditional chemical synthesis is expensive, generates some toxic intermediates and requires a reduction step under high hydrogen pressure. Biological production of 1,3-propanediol could be an attractive alternative to the traditional chemical methods. Moreover, crude glycerol which is a by-product of biodiesel production, can be used. We constructed a recombinant Escherichia coli strain producing 1,3-propanediol from glycerol by introducing genes of the dha operon from Clostridium butyricum 2CR371.5, a strain from our collection of environmental samples and strains. The E. coli strain produced 3.7 g of 1,3-propanediol per one litre of culture with the yield of 0.3 g per 1 g of glycerol consumed.
10
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Screening of environmental samples for bacteria producing 1,3-propanediol from glycerol

75%
Dąbrowski S., Zabłotna E., Pietrewicz-Kubicz D., Długołęcka A.
Acta Biochimica Polonica
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2012
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vol. 59
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issue 3
353-356
EN
Twenty nine environmental samples were screened for the presence of anaerobic microorganisms fermenting glycerol with 1,3-propanediol as a final product. Seven samples were then selected for the next step of our research and eight bacteria strains were cultured anaerobically. Seven of them produced 1,3-propanediol with a yield of 0.47-0.58. Six of the the isolated microorganisms were then classified as Clostridium butyricum (four strains), C. lituseburense (one strain), and C. sartagoforme (one strain). We suggest that of all these strains C. butyricum 2CR371.5 is the best 1,3-propanediol producer as producing no lactate as a by-product and growing well on a glycerol-containing medium.
11
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Application of nanofiltration in the process of the separation of model fermentation broths components

75%
Staszak K., Woźniak M. J., Karaś Z., Staniewski J., Prochaska K.
Polish Journal of Chemical Technology
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2013
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vol. 15
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issue 4
1-4
EN
The effectiveness of nanofiltration with the use of ceramic membranes in the process of concentration and separation of fumaric acid or succinic acid from glycerol and citric acid from erythritol was evaluated. It was found that the retention of sodium salts of the acids investigated increased strongly with increasing the pH of the feed solution (depending on the degree of dissociation), while the retention degrees of di- and tricarboxylic acids, erythritol or glycerol were lower than 2%, irrespective of the initial concentration of the solution to be filtered. The results obtained showed that nanofiltration can be considered as one of the purification steps in the process of recovery of salts of organic acids from fermentation broth.
12
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SELECTED PHARMACEUTICAL PROPERTIES OF THERMOSENSITIVE HYDROPHILIC GELS WITH HYDROXYPROPYLMETHYLCELLULOSE CONTAINING LACTIC ACID COMPLEXED WITH CHITOSAN

75%
Małolepsza-Jarmołowska K.
Progress on Chemistry and Application of Chitin and its Derivatives
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2013
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vol. 18
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issue 18
131-138
EN
Gels containing lactic acid complexed with chitosan at a stoichiometric ration 1:1 and 2:1 and 5-25% content of polyoxyethylene glycol 200 are able to move from 25 to 30 cm. The addition of 4% hydroxypropylmethylcellulose besides glycerol increases the movability gels containing lactic acid complexed with chitosan in a stoichiometric ration 1:1 from 25 cm to 28 cm and at 2:1 ratio from 27 cm to 30 cm. Higher concentrations of the poloxamer 407: 23 and 25% result in the movability of 24 to 29 cm The addition of 5-25% glycerol decreases the pH of investigated gels from 3.95 to 4.45 (1:1) and from 3.63 to 4.30 (2:1). The addition of 5-25% 1,2-propylene glycol decreases the pH of investigated gels from 4.00 to 4.46 (1:1) and from 3.70 to 4.33 (2:1). The use of hydroxypropylmethylcellulose allowed to obtain physiological range. The addition of hydroxypropylmethylcellulose reduces the pH and maintains high adhesion.
13
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EFFECT OF A POLYVINYL ALCOHOL AND SELECTED AUXILIARY SUBSTANCES ON THE PROPERTIES OF THERMOSENSITIVE HYDROPHILIC GELS CONTAINING LACTIC ACID COMPLEXED WITH CHITOSAN

75%
Małolepsza-Jarmołowska K.
Progress on Chemistry and Application of Chitin and its Derivatives
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2013
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vol. 18
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issue 18
107-114
EN
Gels containing lactic acid complexed with chitosan at a stechiometric ratio 1:1 and 2:1 and 5-25% content of PEG-200 reveal pH from 3.42 to 4.95. The addition of 20 – 25% poloxamer 407 increases the pH from 4.55 to 5.30 for 1:1 gels and from 4.00 to 4.85 for 2:1 gels. The addition of 0.5% polyvinyl alcohol decreases the pH of the investigated gels from 4.00 to 4.55 for 1:1 gels and from 3.85 to 4.40 for 2:1 gels. The addition of poloxamer 407 at concentrations of 20 to 25% increases the dynamic viscosity from 506.14 to 641.20 for 1:1 and from 540.35 to 692.55 for 2:1 ratios. The addition of 0.5% polyvinyl alcohol increases the dynamic viscosity from 590.20 to 720.63 for 1:1 and from 560.90 to 698.82 for 2:1 ratios. The addition of polyvinyl alcohol and auxiliary substances reduces the pH and maintains high adhesion.
14
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EFFECT OF A DEXTRANE AND HYDROPHILIZING SUBSTANCES ON THE PROPERTIES OF THERMOSENSITIVE HYDROPHILIC GELS CONTAINING LACTIC ACID COMPLEXED WITH CHITOSAN

75%
Małolepsza-Jarmołowska K.
Progress on Chemistry and Application of Chitin and its Derivatives
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2013
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vol. 18
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issue 18
115-122
EN
Gels containing lactic acid complexed with chitosan at a stechiometric ratio 1:1 and 2:1 and 5-25% content of PEG-200 reveal pH from 3.42 to 4.95. The addition of 20 – 25% poloxamer 407 increases the pH from 4.55 to 5.30 for 1:1 gels and from 4.00 to 4.85 for 2:1 gels. The addition of 1.0% dextrane decreases the pH of investigated gels from 4.40 to 4.90 (1:1) and from 4.00 to 4.48 (2:1). The addition of poloxamer 407 at concentrations of 20 to 25% increases the dynamic viscosity from 506.14 to 641.20 for 1:1 and from 540.35 to 692.55 for 2:1 ratios. The addition of 1.0% dextrane increases the dynamic viscosity from 665.23 to 750.28 for 1:1 and from 645.50 to 740.16 for 2:1 ratios. The addition of dextrane and glycerol or 1,2-propylene glycol reduces the pH and maintains high adhesion. The use of dextrane and hydrophilizing substances allowed to obtain physiological range pH.
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