11:00 am - 12:00 pm
318J Agriculture/Forestry Centre (AgFor), Agriculture/Forestry Centre, Edmonton AB
A graduate exam seminar is a presentation of the student’s final research project for their degree.
This is an ALES MSc Final Exam Seminar by Jesse Yuzik. This seminar is open to the general public to attend.
Thesis Topic: Flocculation of a Kaolin Clay Slurry by Utilizing Specified Risk Material
MSc with Dr. David Bressler.
The oil sands are a vital part of the provincial economy in Alberta and oil production in this sector produces large amounts of waste called tailings. The tailings consist of a slurry of clay suspended in process water with residual bitumen present. Reclamation of the land that the tailings ponds occupy is of great concern to the province and the oil producers. One strategy to consolidate this material is to facilitate separation of the solids from the liquid phase using a chemical called a flocculant. Traditional flocculants may not be environmentally sustainable and other alternatives have been sought after. To this end, a waste resource of biological origin called specified risk materials (SRM) has the potential for use in this application.
Specified risk materials are waste proteins from the rendering of cattle that have the potential to contain prion diseases, such as Bovine Spongiform Encephalopathy (mad cow disease). Currently, this material is being land-filled or incinerated and is an economic burden to the industry as well as a liability to the local environment. To first make this material safe to use, it must first be hydrolyzed into its molecular components; peptides. These peptides can then be used in various applications and can also be chemically modified to alter its properties.
In this work, peptides derived from hydrolyzed SRM were tested as a flocculant in a model kaolin clay system. The peptides were then chemically modified using two different approaches. The first modification was an esterification reaction with methanol to modify the functional groups of the peptides. The second modification was a crosslinking reaction with glutaraldehyde to increase the molecular weight of the peptides. The flocculation performance of the modified peptides was tested in flocculation experiments and were compared to the unmodified version. Characterization analyses were also conducted on the various peptide products including Fourier transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), carboxylic acid titration, sodium dodecyl sulphate gel electrophoresis (SDS-PAGE), high performance liquid chromatography (HPLC) and elemental analysis.
To summarize, hydrolyzed SRM peptides can act as a flocculant in this model system. Modification of this material by crosslinking with glutaraldehyde improves the flocculation performance of the peptides in this system and is recommended for future use in real world tailing consolidation applications. The characterization tests confirmed that the crosslinking reaction was occurring as theoretically expected. The use of this material could provide a biodegradable alternative to the synthetic polymers used in the industry, while also providing a source of nitrogen for plant growth during reclamation. This has the potential to convert an economic and environmental burden into a material that could benefit the environment by aiding in the reclamation of oil sand tailing ponds.