Tar From pyrolyzed bagasse was characterized according to its main structural features. Its solubility in NaOH solutions results in an alkaline tar solution (ATS) that exhibits surface active properties. The prepared ATS was successfully used as a foam flotation agent in copper mining, as a foaming agent in foam concrete formation, and as a fluidization agent for Portland cement manufacture. The potentialities of by-products of conventional pyrolysis and carbonization processed are stressed. (C) 1997 Elsevier Science Ltd.