New absorbing products were prepared by reacting tetraethylenepentamine (TEPA) with formaldehyde (CH2O) and different amounts of phenol (TEPA : CH2O : phenol = 1:1:X in moles, where X was 0.2, 0.4, 0.6). The products, called polyalkylenepolyaminophenols (PAP.X), were chemically and physically characterized. Tests with CO2, H2S, and SO2 in different conditions were carried out with different aqueous solutions of PAP.X products. The solution containing 25 g of PAP.4/100 cm(3) was the most advantageous for both the absorption and desorption of CO2, the 10 g/cm(3) of the same PAP.4 for H2S and SO2. The PAP.X products showed to be better than the alkanolamines both in absorption (total capacity, heat, and speed of reaction) and in desorption (faster regeneration at the same temperatures).