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Exploring Large Pore Size Alumina And Silica-Alumina Based Catalysts For Decomposition Of Lignin, Sara Pourjafar, Jasmine Kreft, Honza Bilek, Evguenii Kozliak, Wayne Seames Dec 2018

Exploring Large Pore Size Alumina And Silica-Alumina Based Catalysts For Decomposition Of Lignin, Sara Pourjafar, Jasmine Kreft, Honza Bilek, Evguenii Kozliak, Wayne Seames

Chemical Engineering Faculty Publications

Evaluation of copper doped silica-alumina and γ-alumina catalysts for lignin decomposition was conducted using a suite of chemical analysis protocols that enabled a comprehensive characterization of the reaction product. X-ray diffraction analysis was used to verify the concentration of doped copper on catalyst supports. Then, batch experiments were performed to study the significance of catalyst support type, catalyst dopant concentration, lignin concentration, catalyst-to-lignin ratio, reactor stirring rate and reaction time. Aqueous products were extracted with dichloromethane and analyzed using a detailed gas chromatography-mass spectrophotometry analytical protocol, allowing for quantification of over 20 compounds. Solid residues were analyzed by thermogravimetric analysis …


Foam Materials With Controllable Pore Structure Prepared From Nanofibrillated Cellulose With Addition Of Alcohols, Jinbao Li, Te Song, Huijuan Xiu, Meiyun Zhang, Rui Cheng, Qiang Liu, Xuefei Zhang, Evguenii Kozliak, Yun Ji Dec 2018

Foam Materials With Controllable Pore Structure Prepared From Nanofibrillated Cellulose With Addition Of Alcohols, Jinbao Li, Te Song, Huijuan Xiu, Meiyun Zhang, Rui Cheng, Qiang Liu, Xuefei Zhang, Evguenii Kozliak, Yun Ji

Chemical Engineering Faculty Publications

Low-density foams based on nanofibrillated cellulose (NFC) made from Pinus massonianesoftwood pulp were prepared from NFC aqueous suspensions containing one of four C2–C4alcohols followed by freeze-drying, with the goal of controlling their pore structure and reducing the shrink rate. The foams prepared from NFC suspensions containing ethanol, isopropanol and n-butanol exhibited highly porous structures with a honeycomb-like cellular texture featuring well-defined “cell walls” between the layers. By contrast, the tert-butanol/NFC foam featured a higher number of smaller size pores with irregular shape. The foams prepared by freezing at −196 °C with ethanol also revealed small size pores, with no layered …


An Initial Study Of The Catalytic Reforming Of Crop Oil‐Derived 1‐Alkenes With Hzsm‐5 To Aromatic Hydrocarbons, Shelby Amsley‐Benzie, Swapnil Fegade, Brian Tande, Alena Kubotava, Evguenii Kozliak, Wayne Seames Aug 2018

An Initial Study Of The Catalytic Reforming Of Crop Oil‐Derived 1‐Alkenes With Hzsm‐5 To Aromatic Hydrocarbons, Shelby Amsley‐Benzie, Swapnil Fegade, Brian Tande, Alena Kubotava, Evguenii Kozliak, Wayne Seames

Chemical Engineering Faculty Publications

This study explored the production of aromatic hydrocarbons from the longer‐chain alkenes produced by the pyrolysis/cracking of crop oils. 1‐Tetradecene, serving as a model compound for these alkenes, was reformed in a batch reactor with a HZSM‐5 catalyst to produce a liquid hydrocarbon mixture with a high‐aromatic content. These reactions resulted in a >99% conversion of the 1‐tetradecene feedstock with a yield of up to 22 wt% of aromatic hydrocarbons. Surprisingly, isomers of C3‐substituted benzenes along with xylenes and diaromatics (lower homologs of alkyl‐substituted indanes and naphthalenes) were the main aromatic products rather than their lower‐molecular‐weight (MW) homologs, benzene, toluene, …


Kinetic Modelling And Experimental Studies For The Effects Of Fe2+ Ions On Xylan Hydrolysis With Dilute-Acid Pretreatment And Subsequent Enzymatic Hydrolysis, Hui Wei, Xiaowen Chen, Joseph Shekiro, Erik Kuhn, Wei Wang, Yun Ji, Evguenii Kozliak, Michael E. Himmel, Melvin P. Tucker Jan 2018

Kinetic Modelling And Experimental Studies For The Effects Of Fe2+ Ions On Xylan Hydrolysis With Dilute-Acid Pretreatment And Subsequent Enzymatic Hydrolysis, Hui Wei, Xiaowen Chen, Joseph Shekiro, Erik Kuhn, Wei Wang, Yun Ji, Evguenii Kozliak, Michael E. Himmel, Melvin P. Tucker

Chemical Engineering Faculty Publications

High-temperature (150–170 °C) pretreatment of lignocellulosic biomass with mineral acids is well established for xylan breakdown. Fe2+ is known to be a cocatalyst of this process although kinetics of its action remains unknown. The present work addresses the effect of ferrous ion concentration on sugar yield and degradation product formation from corn stover for the entire two-step treatment, including the subsequent enzymatic cellulose hydrolysis. The feedstock was impregnated with 0.5% acid and 0.75 mM iron cocatalyst, which was found to be optimal in preliminary experiments. The detailed kinetic data of acid pretreatment, with and without iron, was satisfactorily modelled …


Dna Sequence Mediates Apparent Length Distribution In Single-Walled Carbon Nanotubes, Mohammad Moein Safaee, Mitchell Gravely, Caroline Rocchio, Matthew Simmeth, Daniel E. Roxbury Jan 2018

Dna Sequence Mediates Apparent Length Distribution In Single-Walled Carbon Nanotubes, Mohammad Moein Safaee, Mitchell Gravely, Caroline Rocchio, Matthew Simmeth, Daniel E. Roxbury

Chemical Engineering Faculty Publications

Single-walled carbon nanotubes (SWCNTs) functionalized with short single-stranded DNA have been extensively studied within the last decade for biomedical applications due to the high dispersion efficiency and intrinsic biocompatibility of DNA as well as the photostable and tunable fluorescence of SWCNTs. Characterization of their physical properties, particularly their length distribution, is of great importance regarding their application as a bioengineered research tool and clinical diagnostic agent. Conventionally, atomic force microscopy (AFM) has been used to quantify the length of DNA-SWCNTs by depositing the hybrids onto an electrostatically charged flat surface. Here, we demonstrate that hybrids of DNA-SWCNTs with different oligomeric …


Fiber Evolution During Alkaline Treatment And Its Impact On Handsheet Properties, Yun Ji, Yangyang Peng, Anders Strand, Shiyu Fu, Anna Sundberg, Elias Antero Retulainen Jan 2018

Fiber Evolution During Alkaline Treatment And Its Impact On Handsheet Properties, Yun Ji, Yangyang Peng, Anders Strand, Shiyu Fu, Anna Sundberg, Elias Antero Retulainen

Chemical Engineering Faculty Publications

To understand the swelling effects of alkaline treatment on the morphological properties of fibers and physical properties of handsheets, bleached softwood kraft pulp was treated with NaOH at different concentrations. The results showed that the fiber swelling increased, but the shrinkage and elongation of the paper at a NaOH concentration of 6% or higher did not improve. Dissolution of amorphous material occurred during the treatment together with peeling reactions. The fiber length and shape factor decreased and the fines content increased with an increasing alkali concentration. The cellulose crystallinity decreased with an increasing NaOH concentration. This was confirmed by X-ray …


A Magnetically Responsive Biomaterial System For Flexibly Regulating The Duration Between Pro- And Anti-Inflammatory Cytokine Deliveries, Anita E. Tolouei, Nihan Dügler, Rosa Ghatee, Stephen Kennedy Jan 2018

A Magnetically Responsive Biomaterial System For Flexibly Regulating The Duration Between Pro- And Anti-Inflammatory Cytokine Deliveries, Anita E. Tolouei, Nihan Dügler, Rosa Ghatee, Stephen Kennedy

Chemical Engineering Faculty Publications

While inflammation can be problematic, it is nonetheless necessary for proper tissue regeneration. However, it remains unclear how the magnitude and duration of the inflammatory response impacts regenerative outcome. This is partially due to the difficulty in temporally regulating macrophage phenotype at wound sites. Here, a magnetically responsive biomaterial system potentially capable of temporally regulating macrophage phenotypes through sequential, on‐demand cytokine deliveries is presented. This material system is designed to (i) rapidly recruit proinflammatory macrophages (M1) through initial cytokine deliveries and (ii) subsequently transition macrophages toward anti‐inflammatory phenotypes (M2s) through delayed, magnetically triggered cytokine release. Here, the ability of this …