Please join us for our next Virtual Bioenergy Symposium on July 22 from 12:00-1:00pm MDT. This session features two HQP from the University of Alberta.
For information on past sessions, visit our symposium archive page.
Dr. Yeling Zhu
Department of Agricultural, Food and Nutritional Science
University of Alberta
“Bioconversion of specified risk materials for torrefied wood bio-binder application”
As an inedible by-product from the animal rendering industry, ~300,000 tonnes of specified risk materials (SRM) are disinfected each year in Canada, primarily by landfill or incineration. Instead of this costly methods, thermal or alkaline hydrolysis represents a viable technical alternative to valorize SRM. By applying this Canadian Food Inspection Agency-certified strategy, SRM can be processed to produce safe-to-use peptides, which carry various functional groups and can be used as the molecule platform to develop functional biomaterials. One of these value-added applications is the peptide-based bio-binder (or bio-glue) for torrefied wood applications, a renewable solid fuel used for power generation. Bench-scale tests have showed that incorporating bio-binder at a low dosage (≤ 5%) improved the density and mechanical robustness of the made pellets, both of which are of great interest to government and shareholders in terms of reducing transportation cost and improving operation safety. Overall, bio-binder derived from SRM features a great potential in torrefied wood pelleting application.
Dr. Yeling Zhu is a postdoc fellow in Dr. Bressler’s lab. He is working closely with researchers from Northern Alberta Institute of Technology (NAIT) and industrial leaders to valorize specified waste materials, a low-value protein waste stream from the animal rendering industry, into value-added functional materials. Potential applications of SRM-derived materials include biosurfactant, bio-adhesives, and plastic fillers.
Dr. Zhu received his PhD in August 2019 from the Department of Chemical & Materials Engineering, University of Alberta. His PhD study focused on fundamental investigation in the interfacial and colloidal phenomena of multi-phase systems and developing green and low-energy separation techniques, with applications including but not limited to wastewater treatment, crude/heavy oil production, and mineral processing. His expertise also covers designing and synthesizing multifunctional nanomaterials for electrochemical energy storage applications.
Link to presentation (via YouTube)
Arul Mozhi Devan Padmanathan
Department of Chemical and Materials Engineering
University of Alberta
“Investigating primary decomposition pathways of cellulose during the pyrolysis process using first principles methods”
Advances in agriculture and biotechnology has made the production of biomass significantly less expensive than crude oil. Pyrolysis of lignocellulosic biomass is a promising method involving burning at high temperatures (400°C-800°C) in the absence of oxygen to produce a corrosive liquid called bio-oil which can potentially be upgraded to transport fuel. However, development of the pyrolysis process to improve the quality and yield of bio-oil is hindered by the limited knowledge of the underlying chemistry and transport. Though experimental studies can explain the overall kinetics of biomass decomposition during pyrolysis, they fail to provide the fundamental understanding of reaction mechanisms, pathways and energetics. This is crucial to create a ‘building up’ eﬀect, enabling the integration of chemical mechanisms in particle level models and engineering the interplay between chemistry and transport to optimize the product, bio-oil. Hence in this study, the temperature-variant decomposition of cellobiose, a model compound for cellulose, during pyrolysis is investigated using a novel condensed phase transition state (TS) search method (ConTS), benchmarked with Car-Parrinello-molecular-dynamics-Metadynamics. ConTS integrates force-field molecular dynamics with Density-Functional-Theory (DFT) TS-search calculations to include the effect of condensed phase and largely reduces the computational cost. Two primary cellobiose decomposition pathways were hypothesized – at temperatures < 470°C, crystalline cellobiose undergoes an amorphous phase transformation before decomposition; while at higher temperatures, it undergoes direct decomposition. Free-energy analysis of these two pathways was performed using thermodynamic integration method algorithms. In addition, ConTS calculations revealed that the increased inter-sheet hydrogen bonding in the “amorphous” phase stabilizes the transition state and thereby decreasing the activation barrier for the cleavage of the glycosidic bond. This established relationship between the increased hydrogen bonding and the reduction in activation barrier was previously unexplored. The temperature-dependent decomposition pathways and corresponding energetics arises as a result of the change in the molecular arrangement in the condensed phase pyrolysis environment.
Arul Mozhi Devan Padmanathan is a PhD candidate working with Dr. Samir H. Mushrif in the Department of Chemical and Materials Engineering at the University of Alberta. He received his undergraduate degree in Chemical engineering with honors from the Indian Institute of Technology Gandhinagar in 2018. Previously, he worked in the production of ethanol through fermentation of biomass using a carboxylate platform at the Mix-Alco laboratory in Texas A&M University. His current research mainly focuses on delineating the reaction mechanisms of biomass primary decomposition during pyrolysis and in turn enabling efficient downstream processes.
Link to presentation (via YouTube)