Moisture Sorption Isotherms of Leather

Leather is produced by an industry with high economic and industrial importance and is one of the most expensive products in the world. Owing to its important production, moisture characterization of leather has become a topic of extended and varied research works. The goal of this work is to determine sorption isotherms of leather as the impact of climate-controlled sorption isotherms of the leather moisture is still not clear, this property is absolutely necessary, especially in regard to leather drying and storage in order to guarantee its quality prior to its industrial use. The sorption isotherms were determined at different levels of temperature 30 degrees C, 40 degrees C, 50 degrees C and 60 degrees C and the equilibrium moisture content of leather samples was measured within the range of 5 to 90% relative humidity, using the static gravimetric method based on saturated salt solutions. The equilibrium water content decreases with increasing temperature. The isotherms are of type II, according to the classification of Brunauer (1938). Furthermore, the Dent model is found to be the most appropriate for describing the relationship between the equilibrium moisture content, water activity and temperature.