Reactivity of carbonaceous materials modified by copper chloride addition. A thermogravimetric study

The reactivity in air of several carbonaceous materials has been investigated in a thermobalance. The materials studied comprise an activated carbon and different chars formed by pyrolysis of tires, almond shells and sewage sludges. The addition of CuCl2. 2H(2)O to some of these sample chars increases the rate of decomposition or reaction with the oxygen from the air. The main goal of this paper is to deduce when and why the rate increase takes place. For the activated carbon, the temperature value of the maximum weight loss rate changes from about 575 to 350 degreesC when mixed with the copper chloride. Other runs were performed washing the chloride salts after a first stage of decomposition, checking that part of the catalytic effect is maintained. This would prove that the copper chloride is chemically bonded to the structure of some of the chars. (C) 2001 Elsevier Science B.V. All rights reserved.