FACTORS INFLUENCING GOLD ADSORPTION ONTO ACTIVATED CARBON

The adsorption of gold is affected by a number of external factors that affect both equilibrium and kinetic adsorption. The design and operation of an adsorption circuit will be governed by these factors:  Mixing efficiency.  Pulp density.  Particle size of carbon.  Temperature.  Cyanide concentration.  pH.  Ionic strength.  Gold tenor.  Contact time.  Organic poisons.  Inorganic poisons.  Quality of activated carbon - Carbon activity. - Elution grade. activated carbon for gold

An increase in mixing efficiency increases the turbulence of liquid around the carbon granules. This reduces the liquid boundary layer surrounding the carbon granules and allows for faster adsorption. In order to maximize gold adsorption, the carbon must be evenly distributed throughout the concentrate. This is achieved by controlling pulp density. The density of wet carbon is in the region of 1.3 to 1.5 t/m³, thus the density of the pulp must be similar in order to suspend and distribute the carbon evenly. If the pulp density is too low, then the carbon will sink to the bottom of the contactor, if the pulp density of the pulp is too high, the carbon will float. In both cases insufficient mixing will occur, resulting in a lower gold recovery. Activated carbon has a bulk density of 0.500 g/ml and a pore volume of 0.8 ml/g. If the pore volume is filled with water having a density of 1 g/ml and add the two values, the density of wet carbon is typically 1.3 g/ml. coconutactivatedcarbon.com