Abstract

Catalytic wet peroxide oxidation (CWPO) of maleic acid using palm fruit shell, peach stone and cashew nut shell as catalysts was investigated. Physical activation of pyrolised char with carbon dioxide was done at 900°C, 30 min holding time and heating rate of 20°C/min under nitrogen flowrate of 150 cm³/min. The activated carbons had maximum Brunauer Emmett-Teller (BET) surface areas of 389, 428 and 692 m²/g for palm fruit shell, peach stone and cashew nut shell, respectively. The morphology structures of the samples were determined using a scanning electron microscopy (SEM), while thermal stabilities were determined using thermal gravimetric analysis (TGA). The CWPO reactions were performed in a stirred batch reactor at an atmospheric pressure in the presence of H₂O₂ as an oxidant. The results showed that peach stone and palm fruit shell catalysts are more effective for liquid phase oxidation of maleic acid than cashew nut shell and can be applied for catalytic wastewater treatment systems.

Key words: Activated carbon, catalytic wet peroxide oxidation, activation, surface areas.