RESUMO
Studies has been conducted to compare the sorption properties between raw carbons made from olive cake and commercial activated carbons to remove aquatic pollutant such as heavy metal (HM), phenol (Ph), dodecylbenzenesulfonic acid-sodium salt detergent (DBSNa) and methylene blue dye (MB). Effect of acidic treatments by H2SO4, HCl and HNO3 on the sorption properties of olive cake carbon (OCC) were studied by mass titration, SEM photographs, sorption isotherms. It is found that acidic treatment changes the surface properties of OCC but do not enhance its sorption capacity. Compared to commercial activated carbons the OCC derivatives generally are equally able to uptake HM and Ph from solution but MB and DBSNa are not. This different behaviour is to attribute to manufacturing and activation treatments so as surface groups of the precursor sorbent material. For the heavy metals, chromium and silver were removed effectively but to small extent cadmium. This may be because of the various charge densities of metal elements tested. The results of the multiple experiments indicate that sorption of cadmium ions can be significantly improved by the presence of complexing agents sorbed from the carbon. An empirical mathematical form is proposed to correlate experimental data and to compare the performance of the different sorbent materials.
Assuntos
Carbono/química , Óleos de Plantas , Resíduos , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Benzenossulfonatos/química , Benzenossulfonatos/isolamento & purificação , Corantes/química , Corantes/isolamento & purificação , Indústria de Processamento de Alimentos , Ácido Clorídrico/química , Metais Pesados/química , Metais Pesados/isolamento & purificação , Azul de Metileno/química , Azul de Metileno/isolamento & purificação , Microscopia Eletrônica de Varredura , Ácido Nítrico/química , Azeite de Oliva , Fenol/química , Fenol/isolamento & purificação , Porosidade , Ácidos Sulfúricos/química , Tensoativos/química , Tensoativos/isolamento & purificação , Eliminação de Resíduos LíquidosRESUMO
Flavanone glycosides (FGs) and polymethoxylated flavones (PMFs) have been studied in pigmented orange (Citrus sinensis) juices and second-pressure extracts (SPEs) by high-performance liquid chromatography and diode array detector. Detection was performed simultaneously at two different wavelengths: 278 nm (for determination of FGs) and 325 nm (for determination of PMFs). Qualitative distribution patterns of FGs and PMFs in juices and SPEs were similar, although the quantitative results are quite different. An increased narirutin/hesperidin ratio after centrifugation and the presence of high amounts of PMFs in SPEs, which remain unchanged after centrifugation, were observed. Therefore, a simple and affordable procedure to distinguish an orange juice from SPEs was proposed.