FERNANDEZ Maria Emilia
capítulos de libros
Waste from Orange Juice Industrialization as Potencial Biosorbent for Wastewater Treatment
Industrial Waste: Management, Assessment and Environmental Issues
Nova Science Publishers Inc.
Lugar: New York; Año: 2016; p. 83 - 108
Orange (Citrus sinensis) as the main citrus species is one of top-five fruit commodities that dominate the global fruit market. Around 70 million tons of oranges are grown worldwide each year, representing 8.5% of the total fruit production. Approximately, 40-60% of oranges are processed for juice production, but only around a half of every orange is turned into juice. The rest remains as waste, which includes seed, peel, and segment membrane. Generation of these solid wastes is estimated in the range of 14-21 million tons per year, being the peel the major constituent accounting for approximately 44% of the weight fruit mass. Different applications include production of pectin, flavonoid, fiber, pellets for animal feed, as well as simply spread onto soil near production units or burned. However, large amounts of orange wastes are still dumped every year, causing both economic and environmental problems such as high transportation cost, lack of dumping site, and accumulation of high organic content material. Therefore, other effective, sustainable alternatives for using the wastes are highly desirable. With this end in view, the present chapter explores the feasible utilization of orange peels arising from juice production as biosorbent for removal of water pollutants. In this direction, washed peels samples treated with ethanol solution are used. Physicochemical characterization of the peels is carried out by proximate and elemental analyses, Fourier-transformed infrared spectroscopy, N2 adsorption, and scanning electronic microscopy. Their effectiveness in the removal of methylene blue and rhodamine B, as model organic probes, is investigated from batch assays using dilute aqueous solutions. The effects of the solution pH and sample?s dose are examined. Kinetics and equilibrium isotherms of biosorption for both probes are assessed and satisfactorily represented by conventional models. Comparison with other results reported for the removal of the same dyes using orange peels, either mildly treated or carbonized, and of activated carbons developed from orange peels is conducted. Present results show that orange peels subjected to a simple ethanol treatment exhibit a high capability in methylene blue removal, similar or even superior to that of some activated carbons developed from this waste. Therefore, they could be effectively employed as biosorbent for the removal of dyes of similar structure from aquatic environments polluted with this kind of contaminant species.