Researcher's use of crystal X-ray diffraction could change wastewater treatment

A 2019 study in Environmental Science and Technology found traces of pharmaceuticals and hormones in six per cent of groundwater aquifers serving public water supplies across the United States. Contaminants ranged from cancer treatments to immunosuppressants to antibiotics.

While the rates detected were not deemed to pose immediate threats to human health, they do point to the increasing importance of effective wastewater management in the long term.

Victor Quezada is a master’s student in Concordia’s Department of Chemistry and Biochemistry in the Faculty of Arts and Science. His research focuses on metal-organic frameworks that, with proper synthesis, could act as absorbents that remove the low-level contaminants missed by traditional treatment programs.

If my material performs well as an absorbent, it has the potential to revolutionize water treatment processes

How does this specific image relate to your research at Concordia?

Victor Quezada: My work is based on the synthesis of metal-organic frameworks — novel porous crystalline materials — for applications in wastewater treatment. The image shows one of my materials under 10-times magnification using an optical microscope.

Here we can see that the crystallites are between 0.2 and 0.5 millimetres long, which means we can use single crystal X-ray diffraction to determine the spatial arrangement of atoms in the structure. This is one of the many characterization techniques that I use to confirm that the structure of my material is what I predicted it to be.

What is the hoped-for result of your project?

VQ: This crystalline solid, even though it may look dense under the microscope, has open channels with diameters of 13 to 15 angstroms (one angstrom equals one ten-billionth of a metre). These channels, or pores, can be chemically tuned to trap molecules, allowing my material to act as an absorbent for the removal of specific contaminants in industrial and/or domestic waste.

What impact could you see it having on people’s lives?

VQ: If my material performs well as an absorbent, it has the potential to revolutionize water treatment processes. The contaminants we are targeting, which include pharmaceuticals and personal-care products, do not pose an immediate threat. But the constant, long-term exposure of humans and ecosystems to these contaminants can lead to the evolution of multidrug-resistant organisms, reduced fertility in humans and animals and abrupt ecosystem changes, among other issues.

What are some of the major challenges you face in your research?

VQ: For now, the major challenge is to discover the best synthetic conditions to obtain my crystalline porous material in a high yield and with the specific structure that I am targeting. Although I can look to the scientific literature for help, and as a chemist I can make educated decisions based on fundamental understanding, making new materials can still require a lot of trial and error.

The real challenge is when it becomes hard to rationalize my synthetic results based on what is already known in the scientific literature. But this is part of the excitement of being at the forefront of materials discovery.

What first inspired you to study this subject?

VQ: Ever since I was young, I have been aware of the increasing contamination of our environment and the threat it poses to human health and wildlife. I learned about environmental pollution from the news and school talks, and at a specific point in my life I made the decision to combine my love for science with trying to tackle environmental challenges.

What advice would you give interested STEM students to get involved in this line of research?

VQ: Inorganic materials chemistry has a wide breadth of potential applications waiting to be discovered. These can be relevant to industry, human health, energy, the environment and more. It is up to STEM students to choose or discover a target application that they are passionate about.

What do you like best about being at Concordia?

VQ: I like that graduate students get hands-on experience with lab equipment and that we have easy access to it. I believe this improves scientific learning and also speeds up my ability to obtain results and progress my research.

Also, professors at Concordia are so friendly and easy to reach, facilitating scientific discussions and fostering a positive work environment. It has also been great to meet other graduate students from Canada and around the world, and to share ideas and experiences.

In addition, I have the opportunity to be a teaching assistant, which is helping me improve my teaching and communication skills.

Are there any partners, agencies or other funding/support attached to your research?

VQ: The agencies that support my project are the Fonds de Recherche du Québec – Nature et technologies, the Natural Sciences and Engineering Research Council of Canada and the Faculty of Arts and Science. I was also granted the Anne Allen Entrance Scholarship, which has made it possible for me to carry on my studies at Concordia.

Find out more about Concordia’s Department of Chemistry and Biochemistry.