WASTE FROM ORANGE JUICE INDUSTRIALIZATION AS POTENTIAL BIOSORBENT FOR WASTEWATER TREATMENT

M. E. FERNANDEZ; P. BONELLI; A. L. CUKIERMAN

Industrial Waste: Management, Assessment and Environmental Issues

Nova Science Publishers

Lugar: New York; Año: 2016; p. 83 - 108

Orange (Citrus sinensis)as the main citrus species is one of top-five fruit commodities that dominatethe global fruit market. Around 70 million tons of oranges are grown worldwideeach year, representing 8.5% of the total fruit production. Approximately,40?60% of oranges are processed for juice production, but only around a half ofevery orange is turned into juice. The rest remains as waste, which includesseed, peel, and segment membrane. Generation of these solid wastes is estimatedin the range of 14-21 million tons per year, being the peel the majorconstituent accounting for approximately 44% of the weight fruit mass.Different applications include production of pectin, flavonoid, fiber, pelletsfor animal feed, as well as simply spread onto soil near production units orburned. However, large amounts of orange wastes are still dumped every year,causing both economic and environmental problems such as high transportationcost, lack of dumping site, and accumulation of high organic content material.Therefore, other effective, sustainable alternatives for using the wastes arehighly desirable. With this end in view, the present chapter explores thefeasible utilization of orange peels arising from juice production asbiosorbent for removal of water pollutants. In this direction, washed peelssamples treated with ethanol solution are used. Physicochemicalcharacterization of the peels is carried out by proximate and ultimate analyses, Fourier-transformed infraredspectroscopy, N2 adsorption, and scanning electronic microscopy.Their effectiveness in the removal of methylene blue and rhodamine B, as modelorganic probes, is investigated from batch assays using dilute aqueoussolutions. The effects of the solution pH and sample?s dose are examined.Kinetics and equilibrium isotherms of biosorption for both probes are assessedand satisfactorily represented by conventional models. Comparison with other resultsreported for the removal of the same dyes using orange peels, either mildly treatedor carbonized, and of activated carbonsdeveloped from orange peels is conducted. Present results show that orangepeels subjected to a simple ethanol treatment exhibit a high capability inmethylene blue removal, similar or even superior to that of some activatedcarbons developed from this waste. Therefore, they could be effectivelyemployed as biosorbent for the removal of dyes of similar structure fromaquatic environments polluted with this kind of contaminant species.