Invited for this month′s cover is the group of Philip Jessop in collaboration with Hugh Horton at Queen’s University, Kingston. The image shows how “switchable water”, an aqueous solution of switchable ionic strength, can be used to make clay settle out of suspension while still allowing the water to be recyclable. Read the full text of the article at
What prompted you to investigate this topic/problem?
One might imagine that water is the greenest solvent available, but it has one giant flaw: once it has been used, it is contaminated. If one had an easy way to decontaminate water, a method that allows the water to be recycled without expensive purification steps, then water might really live up to its green potential. We designed switchable water solutions to meet that need. We think of it as water with a built-in separation trigger. In this paper, we show that the separation of fine particles can be triggered when needed.
What new scientific questions/problems does this work raise?
Our switchable water contains an amine additive that makes it switchable. Now the challenge is to make that additive as green as possible to protect the environment, while making it as economical as possible so it will be used industrially.
Who designed the cover?
The authors thank the National Science and Engineering Council of Canada, the Canada Research Chairs program, the Ontario Ministry of Training, Colleges, and Universities and the Walter C. Sumner Foundation for funding. PGJ also thanks the Killam Foundation/Canada Council for the Arts for a Killam Fellowship.