Research Interests

Research Interests

Process development for waste stream remediation based on physico-chemical principles
Environmental Modeling

Current Research

Adsorption of metals by bioadsorbents and organics using surface modified petroleum coke.

Use of biology based technologies, such as biosorption, is an attractive method for heavy metal removal from metal-laden effluents due to low cost and high efficiency of the biosorption process. The main objective of this work is to examine the ability of yeast cells to be produced and utilized in a continuous fashion for removing metal ions in water. The yeast cells produced in the continuous bioreactor system provided continuously fresh surface for adsorption of the metals without the need for costly pretreatment steps, such as harvesting, separating, heat-killing, drying, and storage of biomass.

Oil sands industry extracts bitumen from mixed sands and clay by steam water. In order to produce each volume unit of bitumen, three to four volume units of fresh water are needed. At present, there are two different techniques for extraction of bitumen from oil sands, the first one is open pit mining and the second one is in situ extraction technique. The biggest issue for this industry is recycling and recovery of water from tailing water in order to reduce the needs for freshwater. The overall objective of this project is to develop cost-effective adsorption technologies to reduce fresh water consumption and to enable the recovery of residual organics from oil sands process water and tailings, turning residue petroleum coke into highly active adsorbents, while reducing the need for disposal.

Fate and transport of quaternary ammonium compounds in soil amended with biosolids.

Quaternary ammonium compounds (QACs), are cationic surfactants, enhance the bactericidal properties of commercial products and these compounds are resistant to microbial biodegradation, and are used in large quantities. Benzalkonium chlorides are genotoxic in eukaryotic cells in the range between 1.0 to 10 mg L–1, and their release into the environment may cause genetic damage in exposed organisms. In this research, we are characterizing the environmental fate such as adsorption, biodegradation, and transport in soil media of selected QACs.

Bioassays for whole effluent analysis

Microalgae communities are crucial members of a functioning wetland ecosystem. In recent years, the toxicity of industrial chemicals on algae has received extensive attention. In this research we are developing an algal bioassay based on the community level physiological profiling (CLPP) using model pollutants.

Removal of Micropollutants from water

The ubiquitous presence of trace concentrations of numerous organic compounds (micropollutants) such as pharmaceuticals and active ingredients in personal care products in various water streams is of serious concern. We are evaluating various treatment processes such as coagulation, advanced oxidation, and membrane extraction for removal of micropollutants from various water effluents.

Development and application of nanomaterials for water and air purification and hydrogen production

Solar photocatalytic processes are gaining attention for their potential in energy production using water splitting and sacrificial agents. Nano-sized TiO2 is the most widely examined photocatalyst for this purpose. However, the main barriers of implementing TiO2 are the rapid recombination of photo-generated electron/hole pairs and the poor activation of TiO2 by visible light. Doping TiO2 using various noble and transition metals reduces the possibility of electron-hole recombination. Sacrificial reagents also can inhibit rapid recombination of electron/hole pairs as well as recombination of hydrogen and oxygen. These two concepts are being used in this research.

Extraction of organics using super critical CO2

Supercritical carbon dioxide extraction is a promising technology due to the following advantages: carbon dioxide is a ubiquitous compound in nature, it yields zero contamination of analytes in the extract as well as it accommodates extraction of thermally labile compounds. We are using this extraction process to recover valuables from various feedstock. Thermodynamic modeling is employed to simulate the phase equilibria of the systems to determine the solubility of the analytes in CO2 for process optimization.

Application of CFD for jet mixing in wastewater tank

With rising energy costs and a growing focus on energy conservation and carbon footprint reduction, there is increasing demand for energy-efficient aeration technologies. Vertical jet streams introduced from the top of the aeration reactor concurrently mix and aerate while supplying tiny bubbles, resulting in improved performance and energy efficiency of the reactor. Computational fluid dynamics (CFD) is being conducted for process optimization of this type of important reactors.