TY - GEN A1 - Dasgupta, Sunanda A1 - Ay, Peter A1 - Kommolk, Ralf A1 - Su, Xu T1 - Kinetics of Melt Crystallization of a Sunflower Oil-Based Polyunsaturated Fatty Acid Mixture T2 - Chemical Engineering & Technology N2 - Important parameters like supercooling and cooling rates affecting the melt crys- tallization of a polyunsaturated fatty acid (PUFA) mixture obtained from sun- flower oil were investigated and compared via high-resolution polarized-light mi- croscopy. PUFA was thermally characterized in a differential scanning calorimeter and the significant liquid-solid-phase transition temperatures determined were then implemented in the development of specific temperature profiles. Analyzed between two glass slides, induction times were found to decrease with low crystal- lization temperatures and the number of nuclei per unit area increased with high- er supercooling and cooling rates. A comparison between the linear crystal growth rates of pure standards of each of the main fatty acids present in the PUFA mixture and the PUFA mixture itself indicated that the latter is much slower than that of each of its pure components. KW - Differential scanning calorimetry; Fatty acids; Melt crystallization Y1 - 2013 UR - http://onlinelibrary.wiley.com/doi/10.1002/ceat.201200524/abstract U6 - https://doi.org/10.1002/ceat.201200524 SN - 0930-7516 SN - 1521-4125 VL - 36 IS - 7 SP - 1225 EP - 1230 ER - TY - GEN A1 - Dasgupta, Sunanda A1 - Ay, Peter A1 - Schulz, Stephanie T1 - Determination and Comparison of Equilibrium Data of Various Plant-Based Fatty Acid Mixtures T2 - Chemical Engineering & Technology N2 - Multistage melt crystallization of a variety of plant-based polyunsaturated fatty acid (PUFA) mixtures was conducted to obtain an overview on their liquid-solid equilibrium behavior. Crystal fraction and mother liquor samples were analyzed at every stage. Phase behavior diagrams at low saturated fatty acid concentrations were investigated in detail as they are of significant technical relevance with respect to efficient depletion of the saturated content from the samples. A high oleic acid content in the PUFA mixtures led to difficulties in depleting the mother liquor from the saturated content by melt crystallization. Thermograms from the differential scanning calorimetry were supplemented with illustrations which allow a novel interpretation of results and verification of conclusions. KW - Differential scanning calorimeter, Fatty acids, Liquid-solid phase diagram, Metastable zone, Multistage melt crystallization Y1 - 2014 UR - http://onlinelibrary.wiley.com/doi/10.1002/ceat.201300630/abstract U6 - https://doi.org/10.1002/ceat.201300630 SN - 0930-7516 VL - 37 IS - 6 SP - 1002 EP - 1008 ER - TY - CHAP A1 - Eckert, Karl-Andreas A1 - Dasgupta, Sunanda A1 - Selge, Benjamin A1 - Ay, Peter T1 - Liquid solid phase behavior of ternary fatty acid systems of palmitic, stearic, oleic and linoleic acid T2 - Book of Abstracts of the 8th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry Karlsruhe, March 29–31, 2015 N2 - Enrichment of natural unsaturated fractions by melt crystallization processes has already been proved to be effective in prior investigations [1]–[3]. Palmitic, stearic, oleic, linoleic and linolenic acid are the five main fatty acids present in most of these plant based natural oils. There is quite a bit of information about the liquid solid phase behavior of binary mixtures such as palmitic-oleic, stearic-oleic and palmitic-stearic acid mixtures in literature [4]–[6]. Recent investigations have shown phase diagrams of real natural oil based fatty acid systems containing up to 19% saturated content (11% stearic acid and 8% palmitic acid) [7]. Yet, there is hardly any information regarding ternary systems as those of palmitic-stearic-oleic and palmitic-stearic-linoleic acids. In this work, synthetic mixtures have been used in order to obtain a complete overview of the liquid solid phase diagrams of these ternary mixtures. To imitate naturally occurring mixtures, a mixture with 1:1 ratio of palmitic stearic acid was prepared. Varying amounts of either oleic or linoleic acids were added to this mixture in order to obtain the entire range required for the phase diagrams. These mixtures were then subjected to a specific profile with a wide temperature range in a Differential Scanning Calorimeter (DSC) so as to record every phase transition. This study successfully concludes that these complex mixtures could be treated as binary mixtures of their saturated and unsaturated contents. This is because there were essentially two main peaks noted in the DSC thermograms. It is to be noted that there was a third peak, assumed to represent the solid transition, in mixtures containing oleic acid. This has already been shown in detail and discussed in prior investigations [6], [7]. Another major discovery was that the solidus line depends on the type of the unsaturated content, that is, the degree of unsaturation, in the mixture. KW - Phase Diagram, Ternary Mixtures, Fatty Acids, Differential scanning calorimetry Y1 - 2015 UR - http://conferences.abiosus.org/abstract/show/630 UR - http://www.abiosus.org/Book_of_Abstracts_2015.pdf SP - S. 73 PB - abiosus e.V. Conferences CY - Karlsruhe, Germany ER - TY - CHAP A1 - Eckert, Karl-Andreas A1 - Dasgupta, Sunanda A1 - Ay, Peter T1 - Novel techniques to optically characterize melt crystallization kinetics of high oleic sunflower oil based fatty acid mixture T2 - Book of Abstracts of the 7th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry Karlsruhe, March 23–25, 2014 N2 - The rising applications of enriched unsaturated fatty acid fractions are significantly increasing the need for a cheap method of manufacturing such fractions. Melt crystallization is an established method for purification and enrichment of desired fractions from mixtures [1, 2, 3]. Enrichment of such natural unsaturated fractions by melt crystallization processes has already been proved effective in prior investigations [1, 2]. Since then many analytical and investigative methods have been applied on various natural plant oil based poly-unsaturated fatty acid (PUFA) mixtures to generate the much needed fundamental melt crystallization data [1]. One such method is the use of in-situ polarized light microscopy [1, 4, 5]. Some of the important parameters affecting the melt crystallization of PUFA mixtures are nucleation and crystal growth rate. To be able to observe and visualize these micro-scale phenomena, circular polarized transmitted light microscopy was applied. A tempered chamber (Linkam LS 120) containing the sample between two object slides was placed right within the microscope camera setup (Leica DM RME and Leica DFC 500) with a viewing window. With respect to the transmitted light, the sample was placed between two circular polarized filters such that the system is calibrated for optimal visualization. Unlike linear polarization, in this method every crystal independent of its alignment in the sample, delivers an interference color different from its background. This way, the entire crystal structure could be clearly separated from the melt. Nucleation and crystal growth rate of a high oleic sunflower oil based PUFA was measured using this method at 5K supercooling and 10K/min cooling rate. Growth curves for total crystal area and number of crystals were analyzed and illustrated graphically. A typical S- curve is observed for both the cases starting with a lag phase followed by an exponential growth phase and ending in a saturation phase. KW - Polarized light microscopy, PUFA, melt crystallization Y1 - 2014 UR - http://conferences.abiosus.org/abstract/show/559 UR - http://www.abiosus.org/Book_of_Abstracts_2014.pdf PB - abiosus e.V. Conferences CY - Karlsruhe, Germany ER - TY - CHAP A1 - Dasgupta, Sunanda A1 - Ay, Peter T1 - In-situ monitoring and induction time measurements during melt crystallization of plant based fatty acid mixtures in V-form reactor T2 - 6th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry Karlsruhe, March 17–19, 2013 N2 - Enriched plant based unsaturated fatty acid mixtures are increasingly finding applications in various fields like those of production of bio-fuels and polymerization of epoxy resins. In the case of production of epoxy resins, they are highly advantageous due to the presence of multiple double bonds in the fatty acids which provide opportunities for cross linking by substitution. On the other hand, bio-fuels need raw materials with very low crystallization temperatures. This special property can also be attributed to these enriched unsaturated fractions due to their weak inter-molecular interactions owing to the kink in their structures. Melt crystallization has long been established as an optimal method for purification and enrichment of fractions from mixtures [1,2]. Previous studies have shown promising results with regard to enrichment of unsaturated fractions by melt crystallization processes [1]. Melt crystallization kinetics of two plant based poly-unsaturated fatty acid mixtures have been investigated in this study [3]. A high oleic and a high linoleic fatty acid mixture were chosen for comparison purposes. A V-form reactor was developed for optimal in-situ analysis with the help of the focused beam reflectance measurement (FBRM®, Mettler Toledo Ltd., Switzerland) instrument [3]. Enhanced heat transfer especially to deal with the heat given out during crystallization was enabled through minimal volume of sample, optimized mixing and the special shape of the reactor. Important parameters like induction time, mixing speed, etc have been determined and compared as functions of degree of supercooling and composition of PUFA mixtures. In accordance to theory, the induction times in both the cases decreased with increasing supercooling and mixer speed. On the other hand, the high linoleic fatty acid mixture required much higher supercooling (4.4K to 5.4K) than the high oleic mixture (2.2K to 3.2K) for favorable induction times. KW - FBRM, PUFA Y1 - 2013 UR - https://www.researchgate.net/publication/265109649_In-situ_monitoring_and_induction_time_measurements_during_melt_crystallization_of_plant_based_fatty_acid_mixtures_in_V-form_reactor PB - abiosus e.V. Conferences CY - Karlsruhe, Germany ER - TY - CHAP A1 - Dasgupta, Sunanda A1 - Ay, Peter T1 - Enrichment of unsaturated fractions in a Linseed oil based fatty acid mixture by melt crystallisation T2 - 5th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry, Karlsruhe, Germany N2 - Enriched plant based unsaturated fatty acid mixtures are increasingly finding applications in various fields like those of production of bio-fuels and polymerization of epoxy resins. In the case of production of epoxy resins, they are highly advantageous due to the presence of multiple double bonds in the fatty acids which provide opportunities for cross linking by substitution. On the other hand, bio-fuels need raw materials with very low crystallization temperatures. This special property can also be attributed to these enriched unsaturated fractions due to their weak inter-molecular interactions owing to the kink in their structures. Melt crystallization has long been established as an optimal method for purification and enrichment of fractions from mixtures [1,2]. Previous studies have shown promising results with regard to enrichment of unsaturated fractions by melt crystallization processes [1]. Melt crystallization kinetics of two plant based poly-unsaturated fatty acid mixtures have been investigated in this study [3]. A high oleic and a high linoleic fatty acid mixture were chosen for comparison purposes. A V-form reactor was developed for optimal in-situ analysis with the help of the focused beam reflectance measurement (FBRM®, Mettler Toledo Ltd., Switzerland) instrument [3]. Enhanced heat transfer especially to deal with the heat given out during crystallization was enabled through minimal volume of sample, optimized mixing and the special shape of the reactor. Important parameters like induction time, mixing speed, etc have been determined and compared as functions of degree of supercooling and composition of PUFA mixtures. In accordance to theory, the induction times in both the cases decreased with increasing supercooling and mixer speed. On the other hand, the high linoleic fatty acid mixture required much higher supercooling (4.4K to 5.4K) than the high oleic mixture (2.2K to 3.2K) for favorable induction times. References [1] S. Dasgupta, N. Dreiack, P. Ay, presented at the 5th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry (Eds: J.O. Metzger, M.A.R. Meier), Karlsruhe 2012 [2] G.F. Arkenbout, Melt Crystallization Technology, Technomic Publishing Company Inc., Pennsylvania 1995 [3] S. Xu, Master thesis, Chair of Mineral Processing, Processing of Biogenous Resources, Brandenburg University of Technology, Cottbus 2010 KW - Linseed oil, melt crystallization, unsaturated fatty acids, differential scanning caloriemetry Y1 - 2012 UR - http://conferences.abiosus.org/abstract/show/391 SP - S. 93 ER - TY - GEN A1 - Dasgupta, Sunanda A1 - Rettig, Florian A1 - Ay, Peter T1 - Nucleation kinetics during melt crystallization of plant based high oleic and linoleic polyunsaturated fatty acid mixtures T2 - Crystal Growth & Design N2 - Nucleation kinetics of high linoleic and high oleic polyunsaturated fatty acid (PUFA) mixtures were investigated during melt crystallization by means of an Focused beam reflectance measurement (FBRM) sensor. Samples were analyzed thermally and chemically in the Differential Scanning Calorimeter (DSC) and Gas Chromatograph (GC) respectively. Investigations showed that a high oleic content in the PUFA mixtures lead to higher induction times, τi. Unlike previous investigations, a clear relation between τi and cooling rates was established. τi increases with increasing cooling rates and decreasing supercooling. Activation energies of nucleation, ∆Gc' were determined by means of the Fisher Turnbull equation wherein ∆Gc' decreases exponentially with increasing supercooling. Investigations and further evaluations conclude that while the plot establishes the effect of supercooling on ∆Gc' , it does not incorporate the effects of molecular diffusion or the cooling rate. Hence, 3D modeling was performed to visualize the combined effects of cooling rate and supercooling on induction time. KW - Melt crystallization, Focused beam reflectance method, Differential Scanning Calorimeter, Fatty Acids, Induction time, Gibbs free enthalpy of crystallization, Fisher Turnbull equation, Supercooling, Activation barrier Y1 - 2015 UR - http://pubs.acs.org/doi/abs/10.1021/acs.cgd.5b01432 U6 - https://doi.org/10.1021/acs.cgd.5b01432 SN - 1528-7505 VL - 16 IS - 2 SP - 861 EP - 866 ER - TY - GEN A1 - Oyegbile, Benjamin A1 - Ay, Peter A1 - Narra, Satyanarayana T1 - Optimisation of micro-processes for shear-assisted solid-liquid separation in a rotatory batch flow vortex reactor T2 - Journal of Water Reuse and Desalination N2 - This paper reports the study of micro-processes in a novel pre-treatment technique using a pellet forming batch flow vortex reactor of cylindrical shape that consists of axially revolving rotor plates between fixed stator plates. The suspension was first mixed with high molecular weight synthetic polymers by stirring for approximately 50 seconds and then agitated for 20 minutes. The process was optimised for a number of operating conditions including polymer type and dosing regimen, rotation speed, wall-plate gap distance, residence time and suspension filling method. The results of the investigation show that optimising a number of process variables that influence floc formation and growth, along with specific apparatus construction and geometry, help to maintain the suspension in a metastable state that is crucial for the formation of pellet-like compact agglomerates with better dewaterability and uniform aggregate size. A maximum dry solids content of 28.3% after gravity dewatering through a 0.5 mm sieve was recorded during the investigation, with a maximum particle removal efficiency of 97.5%. KW - floc stability, hydrodynamics, pelleting flocculation, sludge, turbulence Y1 - 2015 UR - www.iwaponline.com/jwrd/up/jwrd2015057.htm U6 - https://doi.org/10.2166/wrd.2015.057 VL - 6 IS - 1 SP - 125 EP - 136 ER - TY - GEN A1 - Eckert, Karl-Andreas A1 - Dasgupta, Sunanda A1 - Selge, Benjamin A1 - Ay, Peter T1 - Solid liquid phase diagrams of binary fatty acid mixtures - Palmitic/stearic with oleic/linoleic/linolenic acid mixture T2 - Thermochimica Acta N2 - The solid liquid phase diagrams of binary mixtures of the five main saturated and unsaturated fatty acids present in most edible plant oils have been determined in this paper. These binary mixtures comprise of a saturated fatty acid, either palmitic (C16:0) or stearic (C18:0) and an unsaturated one, oleic (C18:1), linoleic (C18:2) or linolenic (C18:3) acid. Differential scanning calorimetry (DSC) was used to obtain an overview of the solid liquid transition behaviour including the metastable ranges of these mixtures. In order to describe all the phase transformations in these systems, the boundary functions have been determined and compared. Phase diagrams determined, illustrate characteristic behaviour in accordance to literature. This work specifically focuses on to describe the solid liquid transitions of the mixtures and not on every single transition or reaction. This paper contributes to the elucidation of the phase behaviour of these important mixtures which are applied in diverse industries. KW - Binary mixtures; Solid liquid equilibrium; Saturated and unsaturated fatty acids; Phase diagram; DSC Y1 - 2016 UR - http://www.sciencedirect.com/science/article/pii/S0040603116300193 U6 - https://doi.org/10.1016/j.tca.2016.02.008 SN - 0040-6031 VL - Vol. 630 SP - 50 EP - 63 ER - TY - GEN A1 - Dasgupta, Sunanda A1 - Dreiack, Nadine A1 - Ay, Peter T1 - Melt crystallization kinetics for enrichment of highly unsaturated fatty acid fractions based on Linseed oil T2 - Journal of Environmental Research And Development N2 - Naturally occurring plant based fats and oils have a huge potential as renewable resources to synthesize chemically new products apart from being widely used as ingredients in various kind of food and cosmetics. Oils are triglycerides which are basically tri-esters made of glycerol and three fatty acids. The latter finds application on one hand as raw material for the polymerization of epoxy resins whereas on the other in the manufacturing of biodiesel amongst others. Melt crystallization as a method to enrich a fatty acid mixture with higher unsaturated fractions is becoming increasingly established. A polyunsaturated fatty acid mixture with high concentration of linolenic acid (C 18:3) was chosen for this work. This linolenic oil fatty acid rich mixture was subjected to different temperature profiles in order to optimize maximum yield of unsaturated fatty acid in the mother liquor post isothermal centrifugal separation. The influence of the temperature profile on the quality of the desired product was thereby investigated. To examine the exact composition of the resulting product several analytical methods like Differential Scanning Calorimetry (DSC) and Gas Chromatography (GC) were developed and performed. Product compositions with a total saturated content (C16:0 - palmitic acid and C18:0 - stearic acid) of below 3% was achieved successfully. KW - melt crystallization KW - linseed oil KW - poly-unsaturated fatty acid mixture KW - differential scanning calorimetry KW - gas chromatography Y1 - 2016 UR - http://www.jerad.org/ppapers/dnload.php?vl=11&is=1&st=1 SN - 0973-6921 SN - 2319-5983 VL - 11 IS - 1 SP - 1 EP - 6 ER - TY - CHAP A1 - Ay, Peter A1 - Glaser, Claudia A1 - Logsch, Florian A1 - Narra, Satyanarayana A1 - Gemende, Bernhard A1 - Gerbeth, Anja A1 - Riedel, Tobias A1 - Pausch, Nicole A1 - Leiker, Matthias A1 - Bäde, Bianka A1 - Heiduschke, Rene T1 - Micro-structured Iron (III) hydroxide agglomerates with high porosity as adsorbents T2 - Proceedings of the XXVIII International Mineral Processing Congress (IMPC 2016), September 11-15, 2016, Québec City, Canadian Institute of Mining, Metallurgy and Petroleum N2 - This study focusses on the production of micro-structured agglomerates with high porosity from iron (III)-hydroxide-containing materials as adsorbent. A fractal structure of the agglomerates was created through a two-stage agglomeration process. Developing porous structures was necessary to increase the adsorption capacity. Various materials were used for the agglomeration experiments: i) filter cake (dry matter content 23 to 27 wt.-%); ii) FerroSorp®DGμ, a product which is already being used commercially for various applications in water cleaning. These materials in the pristine state have different characteristics such as dry matter content and particle size distribution. The desired optimised agglomerates can be achieved with the help of additives or binders, respectively. Additionally, the agglomeration process parameters play a vital role. In order to produce agglomerates with high porosity, the process was carried out in two steps. Firstly, FerroSorp®DGμ (d90 < 30 µm) was agglomerated jointly with the aforementioned filter cake in an Eirich intensive mixer (particle size range 125 µm < d90 < 500 µm). The second agglomeration step post drying was carried out in a pelletisation disc or in an Eirich intensive mixer with the addition of polymeric binders (up to particle sizes ranging from 2 to 4 mm). Agglomerates were characterised both in short and long term loading tests using phosphate as model ion. Contact times were less than 10 min, similar to practical application in percolation columns, or more than 7 days, respectively. The results show that the agglomerates produced in the two-stage pelletisation process have more advantageous properties like better accessibility of the active sites obtained by specificly influencing the particle size distribution during the two-stage pelletisation process. KW - Microstructured agglomerate KW - Iron(III)-hydoxide-containing material KW - adsorption capacity Y1 - 2016 SN - 978-1-926872-29-2 ER - TY - CHAP A1 - Markowski, Jens A1 - Ay, Peter A1 - Pempel, Harry A1 - Logsch, Florian T1 - Recycling of metal-coated plastic parts from end-of-life-vehicles (ELV) with biotechnological methods T2 - Proceedings of the XXVIII International Mineral Processing Congress (IMPC 2016), September 11-15, 2016, Québec City, Canadian Institute of Mining, Metallurgy and Petroleum N2 - Due to the European Directive 2000/53/EC on end-of-life-vehicles, from 2015 on more than 95% of car materials have to be recycled. In order to recycle the materials back into the economic cycle, it is necessary to produce products with high quality and purity. Plastic components in cars, which are coated with metals by vapour deposition or electroplating, have a wide circulation (e.g., as cladding panel or trim strip for interiors and exteriors). In the end-of-life-vehicle recycling process, these plastic-metal composites are not considered in usual technologies (car shredder) and are not separated from Automotive Shredder Residue. These parts can be separated by optical or HF-detection sorting and then introduced to a specific treatment. Experiments with a specially developed bioleaching configuration showed that the thin coatings, which consist mainly of copper, nickel and chromium, can be removed efficiently from the polymer base materials by a bioleaching solution with Acidothiobacillus ferrooxidans as a leaching agent. The solution used was produced in special fermenters with a 9K-nutrient salt media. During the bioleaching process at 35°C maximum temperature, most of the copper is dissolved and the other metals accumulate as metal sludge. The bacterial cultures based on A. ferrooxidans are robust and resilient. After a 48-hour bioleaching period while the composites were stirred regularly with ventilation, the plastic particles were completely free from metallic coatings. The metal components are separated for further use: undissolved components (mainly Ni and Cr) are separated by decantation of the solution; dissolved copper recovey is carried out by cementation of copper. The cementated solid contains ~98% Cu, along with small amounts of other metals. With the bioleaching process, good separation and re-utilization of the metallic coatings is possible. The cleaned plastic parts were prepared by compounding for new applications with injection-moulding. KW - Bioleaching, Recycling, Plastic-Metal-Composites, End-of-life-vehicles Y1 - 2016 SN - 978-1-926872-29-2 ER - TY - GEN A1 - Eckert, Karl-Andreas A1 - Dasgupta, Sunanda A1 - Selge, Benjamin A1 - Ay, Peter T1 - Construction and comparison of solid liquid phase diagrams of binary sat-sat and unsat-unsat fatty acid mixtures comprising two of palmitic/stearic/oleic/linoleic/linolenic acid T2 - Journal of Environmental Research And Development N2 - In this paper, binary phase diagrams of the five main fatty acids present in edible oil based mixtures are shown. While previously the binary systems of one saturated and one unsaturated acid were investigated, in this work the binary mixtures comprise of palmitic (C16:0) and stearic acid (C18:0) or a binary mixture of oleic (C18:1), linoleic (C18:2) or linolenic acid (C18:3). In order to obtain the phase diagrams with all the solid liquid and solid phase transitions, the mixtures were analyzed by means of Differential Scanning Calorimetry (DSC). Phase change boundary functions based on thermodynamic models and experimental values were fitted and compared. The phase diagrams obtained show behaviors in good agreement to literature. The paper contributes to the deeper understanding of the essential phase change effects during industrial crystallization processes. KW - Binary mixtures KW - Solid liquid equilibrium KW - Saturated and unsaturated fatty acids KW - Phase diagram KW - DSC Y1 - 2016 UR - http://www.jerad.org/ppapers/dnload.php?vl=10&is=4&st=612 SN - 0973-6921 SN - 2319-5983 VL - 10 IS - 4 ER - TY - GEN A1 - Klose, Markus A1 - Reinhold, Romy A1 - Logsch, Florian A1 - Wolke, Florian A1 - Linnemann, Julia A1 - Stoeck, Ulrich A1 - Oswald, Steffen A1 - Uhlemann, Martin A1 - Ballach, Juan A1 - Markowski, Jens A1 - Ay, Peter A1 - Giebeler, Lars T1 - Softwood lignin as a sustainable feedstock for porous carbons as active material for supercapacitors using an ionic liquid electrolyte T2 - ACS Sustainable Chemistry & Engineering KW - porous carbons KW - lignin KW - supercapacitors Y1 - 2017 VL - 5 IS - 5 SP - 4095 EP - 4102 ER - TY - CHAP A1 - Markowski, Jens A1 - Pempel, Harry A1 - Ay, Peter T1 - Recovery of nickel-containing coatings with hydro-biotechnological methods T2 - COM 2017, Conference of Metallurgists (MetSoc), The 56th Annual Conference of Metallurgists, hosting World Gold and Nickel-Cobalt, August 27-30, 2017, Hyatt Regency Vancouver, British Columbia, Canada N2 - Metal-coated thermoplastic parts find more and more functional and aesthetic applications in the interior and exterior of cars. The vapor-deposited or electroplated coatings are usually composed of a plurality of nickel- and chromium-containing layers, which are applied to copper-containing carrier layers on the polymers. Previously, recycling processes are mainly focussed at the recovery or thermal utilization of the plastics. Targeted and selective recycling of the metallic coatings is usually not carried out. Together with several SME, BTU developed a process, in which a complete and separate recovery of all components in high purity is possible with biotechnological methods. The bioleaching is carried out with iron and sulfur-oxidizing bacteria, esp. Acidithiobacillus ferrooxidans. The copper-containing layers are dissolved in the solution; chromium- and nickel-containing particles are precipitated as solids. After the bioleaching, a mechanical separation of the individual metal-containing components and their separate workup are carried out. End-products are metallic copper, a nickel- and chromium-containing solid and the cleaned plastics. The bioleaching ensures a high purity of the end products. Through the use of bacteria, which are also found in nature, the process is environmentally friendly. Compared to chemical leaching using inorganic acids, considerably shorter leaching times can be achieved. In addition to the optimization of the leaching process, the R/D-project also includes the development and testing of the apparatus technology. KW - Bioleaching KW - End-of-life-vehicles KW - electroplated plastics KW - Recycling Y1 - 2017 SN - 978-1-926872-36-0 PB - Canadian Institute of Mining, Metallurgy and Petroleum CY - Vancouver ER - TY - GEN A1 - Eckert, Karl-Andreas A1 - Dasgupta, Sunanda A1 - Selge, Benjamin A1 - Ay, Peter T1 - Novel model for the prediction of SSLE temperatures and crystallization paths of any mixture containing palmitic, stearic, oleic, linoleic and linolenic acid T2 - Thermochimica Acta N2 - A mathematical model for the prediction of phase change temperatures and crystallization paths for mixtures consisting of palmitic (P), stearic (S), oleic (O), linoleic (L) and linolenic acid (Ll) in any distribution is presented in this paper. This model is based on the information gathered from modeled ternary phase diagrams, namely PSO, PSL, PSLl and OLLl, that were based on experimental binary phase diagrams of all possible combinations of these fatty acids. These experimental binary phase diagrams were obtained by means of differential scanning calorimetry and mathematical function fitting, within which the eutectic region of binary palmitic/stearic with oleic/linoleic/linolenic acid was investigated in detail. The basic mathematical model used was previously shown in literature which delivered good results for such systems. The importance of the developed model was then justified by investigations on real and composed synthetic fatty acid mixtures, where a high accuracy of the predicted temperatures could be shown for the technically relevant liquidus and solidus temperatures. A satisfying prediction for thermal events below the first solidus line could be reached as well. This work directly contributes to an enhanced understanding of the thermodynamic and kinetic background of such important mixtures applied in diverse products and industries, thereby showing a large optimization potential for crystallization technologies. KW - Binary mixtures KW - Ternary mixtures KW - Solid liquid equilibrium KW - Saturated and unsaturated fatty acids KW - Phase diagram KW - DSC KW - Modeling Y1 - 2017 U6 - https://doi.org/10.1016/j.tca.2017.03.015 SN - 0040-6031 VL - 652 SP - 126 EP - 140 ER - TY - CHAP A1 - Dasgupta, Sunanda A1 - Glaser, Claudia A1 - Ay, Peter T1 - SLE diagram for a high oleic palm oil based fatty acid mixture at low saturated content T2 - 9th Workshop on Fats and Oils as Renewable Feedstock for the Chemical Industry, March 19-21, 2017, Karlsruhe, Germany N2 - Vegetable oils and their derivatives are increasingly replacing mineral oils in their applications.[1,2] Among other constituents in vegetable oil, both saturated and unsaturated fractions are important raw materials. The latter possesses double bonds which can provide as substrates or raw materials for various chemical industries.[3] Fractionation of these oils or as in our case the Poly-Unsaturated Fatty Acid (PUFA) mixture is required so as to generate favorable compositions according to applications. Generation of Solid Liquid Equilibrium (SLE) phase diagrams for real mixtures is extremely important to enable a thorough understanding of the thermodynamics of the fractionation process of crystallization. The PUFA mixture was fractionated in a multistage scrubbing layer crystallizer. The product was put into a decanter centrifuge so as to fractionate them into mother liqor and crystal fraction. The temperature in the jacket was maintained such that △T< 5K from the liquidus point obtained from the Differential Scanning Calorimeter (DSC) thermal analyses. Each crystallizer was also maintained at a temperature 5K below the previous one. This way a slow and successive cooling of the PUFA was achieved such that probes from different fraction could be obtained. They were analyzed thermally and chemically in the DSC and Gas Chromatography – Flame Ionization Detector (GC-FID) setup respectively.[4] Similar to previous literature as in [5], technically relevant partial SLE diagrams for high oleic palm oil was created by fractionating the mixture in a scrubbed layer crystallizer along with their metastable range were determined.[6] Y1 - 2017 PB - Abiosus e.V. CY - Oldenburg ER - TY - CHAP A1 - Logsch, Florian A1 - Glaser, Claudia A1 - Balz, Jessica A1 - Ay, Peter A1 - Leiker, Matthias A1 - Heiduschke, Rene T1 - Experimental studies of the pelletizing-flocculation process of ironhydroxide containing suspensions in a Taylor-Couette-Reactor T2 - Abstracts of the XXIX International Mineral Processing Congress : 17-21 september, 2018 N2 - The treatment of iron-hydroxide-containing water from ground water and surface water is achieved by a combination of the process steps of flocculation and subsequent mechanical dewatering. The aim is to create solid pellet structures by extending the structure forming flocculation process with a build-up pelletizing process which can be transferred directly into a drying unit. A Taylor-Couette-reactor (diameter of the inner cylinder – 40 mm, gap width – 5 mm) was used for these experimental studies. To produce the necessary flow profile the inner cylinder was rotated at a speed of 230 rpm. The iron hydroxide-containing suspension (dry matter content: 2 mass %) was added simultaneously with the addition of a cationic high-molecular flocculant in various flocculant dosages and residence times of 5 to 15 min. The pellets were examined for parameters such as geometric dimensions, dry substance content and dewatering behaviour. As the results show, there is a direct relationship between the residence time and the geometric dimensions of the pellets. After a residence time of 5 min, round pellets with an average diameter of 6 mm were formed. With an increase in the residence time up to 15 min, a compaction of the pellets could be observed, which resulted in an increase in the dry substance content of 8.0 to 11.2 mass % on average. After completion of the pelletizing process, the pellets were mechanically dewatered by filtration. By applying this innovative wet pelletizing of iron-hydroxide containing suspensions in a Taylor-Couette-reactor, it is possible to carry out the process of flocculation combined with the pellet formation with simultaneous pellet compaction in a single process step. The resulting pellet structures are distinguished from conventional floc structures by an improved water discharge capacity. After classification the pellets can be marked directly as easy-to-handle bulk material, suitable as feedstock in percolation columns for the purification of contaminated fluid streams KW - Flocculation, wet-pelletizing, Taylor-Couette-reactor, water purification, Iron(III)-hydroxide-containing material, pelletizing-flocculation Y1 - 2018 SN - 978-5-98191-086-9 SP - 189 PB - Ore and Metals, Publishing House, Moscow CY - Moscow ET - 1. Auflage ER -