Characterization of mango pit as raw material in the preparation of activated carbon for wastewater treatment

Utilization of wastes as adsorbents or as raw materials in the preparation of activated carbon for environmental applications is an interesting alternative to commercial activated carbon commonly used for pollutants removal. Physical and chemical characteristics of the raw material play an important role in the properties of the carbonized waste. In this work two components of mango pit (the outer husk: SEMAVE-H and the inner seed: SEMAVE-S) were studied. The materials without carbonization were characterized by ultimate and proximate analysis. Cellulose, hemicellulose and lignin were quantified by the Crampton-Maynard, neutral detergent fiber (NDF) and acid detergent fiber (ADF) methods. The thermal behavior was studied by thermogravimetry and adsorption isotherms of water vapor, methylene blue and nitrogen were measured. Optic microscopy, Boehm's titration and IR spectroscopy were also used. SEMAVE-H contained more cellulose (39.4%) than hemicellulose (15.6%) and the inverse was revealed in SEMAVE-S. The thermal behavior of SEMAVE-S was complex; four peaks appeared in the DTG curves being the more intensive at 234 and 348 degrees C. For the husk and the seed S-sp <= 100 m(2) g(-1) and the acid groups were the most abundant in both materials. (C) 2007 Elsevier B.V. All rights reserved.