Abstract: The effect of surface active agent to bacterial leaching and the adsorption law leaching chalcopyrite under different pulp density, particles, primary pH value were studied. The results show that in the initial phase, the bacterial adsorption quantity increases along with time, in the stationary phase, over 90% bacteria are adsorbed on the surface of ores. When the leaching time is extended, the bacterial adsorbance will decrease. The surface active agent tween-20 can accelerate the oxidative dissolution of chalcopyrite, promote the leaching speed, but can't promote the leaching rate, tween-20 also can inhibit the leaching process and baleful to the growth of bacteria when above the critical value.

Key words: Bio-leaching, Chalcopyrite, Bacteria adsorption, Surface active agent