Category: Research

Mechanism of Humins Formation during Catalytic Conversion of Cellulose-Derived Carbohydrates

MSE SEMINAR
Friday, April 20, 2012
11:00 am – 12:00 pm
Room 610, M&M Building
Carl R. F. Lund
Dept. of Chemical and Biological Engineering
University at Buffalo, Buffalo, NY

John & Virginia Towers Distinguished Lecture Series

Abstract

Cellulosic biomass represents a potential resource for sustainable production of fuels and chemicals. When cellulose is hydrolyzed using mineral acids as catalysts, dark-colored, tarry solids known as humins form as undesirable by-products. The formation and growth of humins have been investigated using small batch reactors, and the resulting humins have been characterized, primarily using scanning electron microscopy and infrared spectroscopy. The aqueous phase free energies of proposed reaction intermediates have been computed using quantum chemistry. The experimental and computational results are consistent with a sequential pathway for the formation of humins. The primary reaction proceeds through the sequential conversions of cellulose to glucose (perhaps) to fructose to HMF to levulinic acid. The predominant pathway for the formation of humins involves the conversion to HMF to 2,5-dioxo- 6-hydroxyhexanal (DHH). DHH rapidly undergoes aldol addition/condensation with available aldehydes or ketones. The resulting adduct then polymerizes to form humins. The experimental studies have shown that humin morphology, size and size distribution are affected by solvent choice. It has also been established that chemical functional groups can be added to the humins during or after their formation. These finding might lead to ways to convert humins from a waste byproduct to a more valuable commodity.

Bio: Dr. Lund is a SUNY Distinguished Professor. He was a department chair from 1997 to 2006. He obtained his B. S. from Purdue University in 1976 and Ph. D. from University of Wisconsin–Madison in 1981. His research interests include heterogeneous catalysis for energy and environmental applications, reaction engineering of membrane reactors, and biomass conversion. He received many awards, including NSF Presidential Young Investigator, SUNY Chancellor’s Award for Excellence in Teaching, and Lilly Teaching Fellow. He published more than 70 peer-reviewed papers.

Characterization of Trap States in HfO2 with Atomic Scale Spatial Resolution Using Single Electron Tunneling Force Spectroscopy

MSE SEMINAR
Friday, April 13, 2012
3:00 pm – 4:00 pm
Room 610, M&M Building
Dustin Winslow
University of Utah
Abstract
The rapid advancement of technology has led to increasingly faster and smaller solid state devices. One reason for this rapid development is the dedicated effort to characterize the defects in the dielectric materials used in solid state electronics. While many techniques have been developed over the years to characterize trap states in dielectric materials no technique has allowed for characterization of localized electron and hole trap states, in completely nonconducting films, with atomic scale spatial resolution. This talk will focus on the force detected tunneling techniques developed in the Williams lab at the University of Utah over the last decade, with an emphasis on the recently developed single electron tunneling force spectroscopy (SETFS) technique. The apparent density of localized trap states in HfO2 measured using SETFS will be compared to experimental results and theoretically predicted values found in the literature. The convoluted nature of the apparent energy and physical depth information of the trap states will be discussed, and the methodology to separate this information will be explained. Finally, evidence of mobile charge in HfO2 will be presented and a possible mechanism proposed to explain the irreversible nature of the surface charging.

Hu Attends ACS Meeting

Associate Professor Yun Hang Hu (MSE) attended the 243rd meeting of the American Chemical Society (ACS) in San Diego in late March.

Hu was the program chair of the ACS fuel chemistry division, which featured 68 sessions and 607 papers (a record since 1961) presented by scientists worldwide.

With more than 164,000 members, the ACS is the world’s largest scientific society and one of the world’s leading sources of authoritative scientific information.

The fuel chemistry division (renamed energy and fuels division) is one of 32 technical divisions.

Read more at Tech Today.

MSE Entries in Expo 2012

Expo2012 Undergraduate Expo Entries

SENIOR DESIGN
Title and Representative

Economic Recovery of Alloying Elements from Grinding Swarf
Alicia Steele

Reduce Distortion in Ferritic Nitrocarburizing of Gray Iron
Carol Deming

Fatigue in Stainless Steel Components Produced by Powder Metallurgy & Hot Isostatic Pressing
Samantha Leonard

EZAC Creep Testing Team
Deane Kyle

Effects of Mn and Sn on Ductile Iron
Dale Goodloe

Residual Stress of Gray Iron Brake Rotors
Carol Dem

Waupaca FNC Case Depth
Ashwin, Vekaria

ENTERPRISE TEAMS

Advanced Metalworks Enterprise
Zac Dvorak