PEAT AS AN ADSORBENT FOR DYESTUFFS AND METALS IN WASTE-WATER

The ability of peat to adsorb dyestuffs and metals from wastewaters was investigated. Equilibrium isotherms were determined in order to assess the maximum adsorption capacity of some basic and acidic dyestuffs, and metal ions onto peat, lignite and other adsorbents. Economic evaluations indicated that peat was a particularly attractive adsorbent. Kinetic studies for the adsorption of basic dyes onto peat were undertaken in agitated batch and fixed bed adsorbers. Mass transport models detailed elsewhere were tested and used to predict (a) the concentration decay curve for batch adsorption and (b) the breakthrough curves in fixed bed adsorption. The models tested were single-resistance models and included an estimation of the external mass transfer coefficients.