A new microwave cavity reactor, with the loading capacity of 1 m(3) and microwave injected power up to 6 kW, specially designed and built for cleanly neutralizing paper-based waste, like disposable diapers, is presented. The constructive details of this new system are given and the thermal properties of the materials used to construct the cavity walls are analyzed. The microwave field inside the cavity is also discussed. Moreover, the preliminary experimental results obtained with this reactor, with and without load are presented and examined. They prove that this new device is capable of effective paper-based waste neutralization using microwave power. (c) 2007 Elsevier B.V. All rights reserved.