Adsorption of Hexyl Mercaptan on Sphalerite

CIM Bulletin, 1966

T. Salman and R. F. Robertson Dept. of Metallurgy and Chemistry, McGill University, Montreal, Que.

Adsorption isotherms of hexyl mercaptan vapour on synthetic sphalerite, zinc sulphide and zinc oxide were determined with a gravimetric McBain-Baker micro balance incorporated in the B.E.T. apparatus. Isotherms are given for hexyl mercaptan on synthetic sphalerite at 25 °C, 0.5 °C and 50°C; on zinc sulphide at 25 °C and 1.5 °C; and on zinc oxide at 25°C. All these isotherms are sigmoidal, with a definite change in slope at or close to the monolayer. The amount of mercaptan adsorbed below the monolayer increases almost linearly with relative pressure to P / P0 = 0.8. Above this value, the amount adsorbed increases very rapidly with relative pressure. Hysteresis loops appear in the isotherms for all adsorption-desorption cycles. These loops are completely reversible. It is not possible to desorb the mercaptan monolayer from any of the adsorbents, even at elevated temperatures.
Keywords: Adsorption, Adsorption of Hexyl Mercaptan, Hexyl Mercaptan, hysteresis, sphalerite, zinc oxide, Desorption, Pressure, sphalerite, sulphide, Systems, Temperature, zinc