Observation of enhanced heat dissipation in columns packed with superficially porous particles.

At high flow rates and pressures, columns packed with sub-2 μm particles suffer from efficiency losses due to frictional heating. The thermal environment of the column (insulated or isothermal) can decrease or magnify these losses. While a number of studies have been conducted demonstrating the improved performance (partially due to the benefits of enhanced thermal conductivity) of columns packed with superficially porous particles, none have made a comparison between sub-2 μm fully and superficially porous particles in an isothermal environment where radial thermal gradients are maximized and thermal broadening is amplified. Here we show that when such columns are characterized in a recirculating water jacket (providing an isothermal environment), efficiency loss and changes in retention and mobile phase temperature are reduced for sub-2 μm superficially porous particles compared to sub-2 μm fully porous particles.