@misc{UtgenanntHansenKlepeletal., author = {Utgenannt, Stephan and Hansen, Felix and Klepel, Olaf and Jarczewski, Sebastian and Wach, Anna and Kuśtrowski, Piotr}, title = {Control of porosity and composition of carbon based catalysts prepared by template assisted routes}, series = {Catalysis Today}, volume = {Vol. 249}, journal = {Catalysis Today}, issn = {0920-5861}, doi = {10.1016/j.cattod.2014.10.036}, pages = {38 -- 44}, language = {en} } @misc{KlepelErlitzScholzetal., author = {Klepel, Olaf and Erlitz, Marcel and Scholz, Kerstin and Suckow, Matthias and Taubert, Michael and Utgenannt, Stephan and Garsuch, Arnd}, title = {Template assisted synthesis of porous carbons revisited - where does the porosity come from?}, series = {Microporous and Mesoporous Materials}, journal = {Microporous and Mesoporous Materials}, number = {vol. 224}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2015.11.047}, pages = {163 -- 167}, language = {en} } @misc{ReichardtUtgenanntStahmannetal., author = {Reichardt, Christina and Utgenannt, Stephan and Stahmann, Klaus-Peter and Klepel, Olaf and Barig, Susann}, title = {Highly stable adsorptive and covalent immobilization of Thermomyces lanuginosus lipase on tailor-made porous carbon material}, series = {Biochemical Engineering Journal}, journal = {Biochemical Engineering Journal}, number = {138}, issn = {1873-295X}, doi = {10.1016/j.bej.2018.07.003}, pages = {63 -- 73}, abstract = {Hierarchically structured, porous carbon materials (PCM) were synthesized by sucrose infiltration into template material and subsequent carbonization. Three porous carbon materials were prepared using porous concrete (PCM-01) or silica gel (PCM-02 and 03) as template. Carbon particles from 125 to 200 μm were generated. Surface carboxylic group density was determined with 1.1 mmol/g dry material for each variant. Firstly, tailor-made PCM was evaluated as suitable support for lipase immobilization. Recombinant produced lipase of Thermomyces lanuginosus (TLL) was used as model enzyme. Two independent crude immobilization strategies were applied. Residual activities of up to 8.6 U/g and 31 U/g dry material for adsorptive and covalent immobilization (linkage via EDC) were achieved, respectively. Additionally, TLL was immobilized on commercially available polymethacrylate support showing similar residual lipase activities. Secondly, covalent immobilization was optimized to generate reproducible, highly stable and active immobilizates. Optimized covalent immobilizates showed residual activities of up to 10 U∙g⁻¹ dry carbon material using p-nitrophenyl-palmitate assay and protein loads of up to 45 mg g⁻¹dry carbon material. Covalent bound TLL-PCM showed storage stability for 12 months, remaining 100\% of the initial activity. Operational stability resulted in stable and 100\% active immobilizates over five consecutive cycles of use. Experiments showed that tailor-made porous carbon material is a promising support for lipase immobilization, which is adaptable in shape and dimension.}, language = {en} } @misc{KlepelLangeUtgenannt, author = {Klepel, Olaf and Lange, Felix and Utgenannt, Stephan}, title = {Oxidation of sulfurous acid on carbon catalysts as a test reaction revisited: potential and limitations}, series = {Chemical engineering \& technology}, volume = {41}, journal = {Chemical engineering \& technology}, number = {10}, issn = {1521-4125}, doi = {10.1002/ceat.201800227}, pages = {2087 -- 2092}, language = {en} } @inproceedings{BarigUtgenanntHeineetal., author = {Barig, Susann and Utgenannt, Stephan and Heine, Alexander and Reichardt, Christina and Klepel, Olaf and Schnitzlein, Klaus and Stahmann, Klaus-Peter}, title = {Por{\"o}ses Kohlenstoffmaterial zur Immobilisierung von Lipase-Vergleichende Messungen mit Methacryl-Beads}, series = {Chemie Ingenieur Technik}, volume = {88}, booktitle = {Chemie Ingenieur Technik}, number = {9}, issn = {1522-2640}, doi = {10.1002/cite.201650097}, pages = {S. 1243}, abstract = {Zur Immobilisierung von Enzymen kann man Tr{\"a}ger kaufen oder diese selbst herstellen. In fr{\"u}heren Arbeiten wurde ein Verfahren entwickelt, um hochpor{\"o}se Kohlenstoffmaterialien in beliebigen Dimensionen herzustellen. Als Modell-Enzym zur Immobilisierung wurde die Thermomyces lanuginosus Lipase (TLL) gew{\"a}hlt, die adsorptiv und kovalent an das Material sowie an zwei k{\"a}ufliche Tr{\"a}germaterialien auf Polymethacryl-Basis (Funktionalit{\"a}ten: Ethylendiamin- bzw. Diolgruppen)gebunden werden sollten. Es wurden Kohlenstoffgranulat (d = 125 -200 mm) und zylindrische Monolithe (h = 4 cm; d = 1 cm) synthetisiert. Die adsorptive Immobilisierung ergab am Kohlenstoffgranulat Aktivit{\"a}ten von bis zu 2,5Ug⁻¹ gegen{\"u}ber p-Nitrophenyl Palmitat (pNPP). Bei den zwei k{\"a}uflichen Materialien wurden Aktivit{\"a}ten von bis zu 1,8Ug⁻¹ erreicht. Mit der kovalenten Immobilisierung konnten Aktivit{\"a}ten von bis zu 10Ug⁻¹ am Kohlenstoffmaterial sowie dem Polymethacryl-Material (-OH funktionalisiert) gegen{\"u}ber pNPP erreicht werden. Das Kohlenstoffmaterial ist ein geeigneter Tr{\"a}ger f{\"u}r die TLL, der im Vergleich mit g{\"a}ngigen Materialien Aktivit{\"a}ten in der gleichen Gr{\"o}ßenordnung zul{\"a}sst. Das Porenvolumen des Materials sowie die Makroporosit{\"a}t k{\"o}nnten erh{\"o}ht werden, um Diffusions- und Durchstr{\"o}mungsbarrieren im Monolithen abzubauen.}, language = {de} } @inproceedings{UtgenanntHansenKlepeletal., author = {Utgenannt, Stephan and Hansen, Felix and Klepel, Olaf and Jarczewski, Sebastian and Wach, Anna and Kustrowski, Piotr and Erler, Thomas and Bron, Michael}, title = {A modular concept for the preparation of carbon based catalysts}, series = {Carbon 2015 : innovation with carbon materials; the Annual World Conference on Carbon, Dresden, Germany, July 12 - 17, 2015}, booktitle = {Carbon 2015 : innovation with carbon materials; the Annual World Conference on Carbon, Dresden, Germany, July 12 - 17, 2015}, publisher = {Deutsche Keramische Gesellschaft e.V.}, address = {K{\"o}ln}, pages = {S. 294}, language = {en} } @inproceedings{UtgenanntVormelchertKlepeletal., author = {Utgenannt, Stephan and Vormelchert, Carolin and Klepel, Olaf and Jarczewski, Sebastian and Drozdek, Michal and Kustrowski, Piotr and Erler, Thomas and R{\"u}mmler, Stephan and Bron, Michael}, title = {Template assisted synthesis of porous carbon catalysts with systematically varied properties}, series = {The zeolites : materials with engineered properties : book of abstracts / 7th FEZA Conference, July 3-7, 2017, Sofia, Bulgaria}, booktitle = {The zeolites : materials with engineered properties : book of abstracts / 7th FEZA Conference, July 3-7, 2017, Sofia, Bulgaria}, address = {Sofia}, pages = {S. 199}, language = {en} } @inproceedings{BoelteUtgenanntKlepeletal., author = {B{\"o}lte, Jens-Henning Ingo Holger and Utgenannt, Stephan and Klepel, Olaf and Erler, Thomas and R{\"u}mmler, Stephan and Bron, Michael}, title = {Heteroatom doped porous carbon catalysts with systematically varied properties obtained by template assisted synthesis}, series = {Book of abstracts, 8th International Symposium on Carbon for Catalysis, CarboCat-VIII, 26. - 29.06. 2018, Porto}, booktitle = {Book of abstracts, 8th International Symposium on Carbon for Catalysis, CarboCat-VIII, 26. - 29.06. 2018, Porto}, publisher = {Sociedade Portuguesa de Qu{\´i}mica}, address = {Porto}, isbn = {978-989-8124-22-7}, pages = {S. 69}, language = {en} } @misc{KlepelUtgenanntVormelchertetal., author = {Klepel, Olaf and Utgenannt, Stephan and Vormelchert, Carolin and K{\"o}nig, Mark and Meißner, Andr{\´e} and Hansen, Felix and B{\"o}lte, Jens-Henning Ingo Holger and Sieber, Tim and Heinemann, Robert and Bron, Michael and Rokicinska, Anna and Jarczewski, Sebastian and Kustrowski, Piotr}, title = {Redox catalysts based on amorphous porous carbons}, series = {Microporous Mesoporous Materials}, volume = {323}, journal = {Microporous Mesoporous Materials}, issn = {1387-1811}, doi = {10.1016/j.micromeso.2021.111257}, pages = {12}, language = {en} } @phdthesis{Utgenannt, author = {Utgenannt, Stephan}, title = {Templatgest{\"u}tzte Synthese por{\"o}ser Kohlenstoffmaterialien mit systematisch variierten Eigenschaften f{\"u}r Redox-Reaktionen mit Sauerstoff}, address = {Cottbus ; Senftenberg}, pages = {IV, 206}, language = {de} } @misc{BoelteUtgenanntSchmidtetal., author = {B{\"o}lte, Jens-Henning and Utgenannt, Stephan and Schmidt, Max and Klepel, Olaf and Bron, Michael and Rokicińska, Anna and Jarczewski, Sebastian and Kuśtrowski, Piotr}, title = {S-doped and N+S-co-doped carbon catalysts in redox reactions}, series = {Microporous and mesoporous materials}, volume = {407}, journal = {Microporous and mesoporous materials}, publisher = {Elsevier BV}, address = {Amsterdam}, issn = {1873-3093}, doi = {10.1016/j.micromeso.2026.114129}, pages = {1 -- 11}, abstract = {In this contribution, the effects of heteroatom doping of porous carbon materials with S and N on their ability to catalyze redox-reactions involving the activation of molecular oxygen were investigated. For this purpose, a library of in total 54 undoped, S-doped and N + S-co-doped porous carbons was obtained via a template-based synthesis procedure using mesoporous silica gel as the template. To understand the influence of S on the properties of the doped carbons three different S-containing precursors, namely dimethyl sulfoxide (DMSO), p-toluene sulfonic acid and thiophene, were used. In order to investigate possible synergistic effects of S- and N-co-doping, urea was employed as the sole N-containing precursor. The obtained carbon catalysts were characterized by selected methods such as N2-physisorption at 77 K, X-ray diffraction (XRD), Raman spectroscopy, elemental analysis and X-ray photoelectron spectroscopy (XPS). Each carbon catalyst was tested in the oxidation of sulfurous acid (OSA) to sulfuric acid, the electrochemical oxygen reduction (ORR) and the oxidative dehydrogenation (ODH) of ethylbenzene. Owing to the similar textural and structural properties achieved through template-based synthesis of the carbon catalyst library, the results of the catalytic redox-reactions could directly be related to the respective heteroatom dopant. The observed trends indicate that in these redox-reactions S-species behave somewhat similar to O-species bound on the carbon surface. Furthermore, it can be shown that N + S co-doping rather combines the positive and negative effects of the individual dopants on the activity, than creating a synergistic effect that surpasses the individual contribution.}, language = {en} }