Design and development of potassium formate based atmospheric water harvester

Abstract

Potassium formate, the potassium salt of formic acid, is an inexpensive, non-corrosive, non-toxic, and bio-degradable desiccant that has not been considered thus far in atmospheric water harvesting applications.ster is proposed that utilizes an aqueous solution of potassium formate as the medium for moisture absorption during the night when the ambient relative humidity is high, and desorption of absorbed moisture from the desiccant solution during the day using solar energy. A simple prototype was constructed that was able to extract 1.9 L of water∙m−2 of solar area∙day−1 with a moisture uptake of 0.34 kgwater∙kgsalt−1at 25 °C and 79% RH and 0.29 kgwater∙kgsalt−1 at 25 °C and 65% RH.