Spicing up CO2
Post by Frank Kvietok - Director of Application Development
Carbon dioxide is pretty amazing stuff. Physical properties stemming from its unusual quadrupole moment and its well-studied phase behavior lead to an incredible number of applications from champagne to dry ice. As a liquid, its non-polar and very low viscosity nature allow it to penetrate deeply into complex structures, like fabrics, while being very gentle in comparison to water. Garments as different as silk blouses to oil-field coveralls love a bath in liquid CO2!
With the addition of chemistries to broaden the cleaning profile or to apply a treatment, CO2 can do even more. So, where do these technologies come from? The textile industry has been thinking ‘water’ for centuries. Plus, it’s not easy to do classic bench-top experimentation. Given that carbon dioxide is a gas at normal atmospheric conditions, a beaker full of liquid CO2 isn’t very well-behaved, to say the least!
We have found a variety of approaches to be helpful. They’re all based on two tenets:
- Understand what you’re trying to accomplish clearly enough to be able to explain to others or to be able to ‘think like a molecule’.
- Be flexible, creative, and humble as you search for solutions!
Partnering is huge, there’s a lot to learn from others. We focus on both the chemical supplier industry and end-users (mills, commercial cleaners, brands,… - our end customer). With chemical providers, a key strategy has been engaging with the developers, asking for their help in order to identify technologies already developed and getting them intellectually engaged. While not directly textile related, a lot of work that has gone into fields such as oil recovery and and ‘hi-tech’ cleaning (electronics, mechanical), can translate very well to a liquid CO2 environment.
In our experience, chemistry developers get super excited about thinking ‘in CO2’, for a change! In addition to defining our challenge, it really helps to highlight the differences our system has versus traditional, such as its closed-loop nature, which allows great flexibility in terms of what chemistry can be used. Since we can easily reclaim and reuse most added chemistries, expense can be thought of very differently. It’s not a ‘one and done’ situation! Similarly, as there’s literally no wastewater discharge, materials that would be very problematic to recover from traditional water systems are easily collected and disposed of in our system.
From our potential customers comes help in defining the challenge, both from an end result or benefit point of view, but also from the position of financial economics and deployment ease. This input is, of course, crucial so we can develop comprehensive solutions. Sometimes these solutions are better approaches to what’s being done in water today, sometimes they are options made possible only through the use of CO2.