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Cystoseira sensu lato (s.l.) species are very important components of coastal marine ecosystems. Despite their ecological importance, the taxonomy of these macroalgae has not been fully elucidated. In this study, Cystoseira s.l. collected from the Sinop coast were diagnosed molecularly and morphologically and and found to be represented by two species, Gongolaria barbata (Stackhouse) Kuntze and Ericaria bosphorica (Sauvageau) D.Serio & G. Furnari. In this study, Cr+6 removal performance in wastewater treatment of algal wastes was discussed and characterization, biosorption kinetics, and isotherms studies were performed. The effects of basic parameters such as initial concentration, pH, and contact time on biosorption capacity were studied and evaluated. The biosorption data were found to be in better agreement with the Freundlich isothermal model and the pseudo-second-order kinetic model. The correlation coefficients were above 0.99 for both congruent models, and the biosorption capacity under optimal conditions was found to be 41.23 mg g-1. According to the results of the study, waste algal biomass can be considered as an effective biosorbent for the removal of Cr+6 from wastewater. [ABSTRACT FROM AUTHOR]

The presence of dyes in the aquatic environment is a global problem because of the negative consequences on the ecosystem quality. Adsorption process is used as a low cost and effective method for removing hazardous dyes. This study investigated removal of Bromophenol Blue from aqueous solutions by Fomes fomentarius and Trametes versicolor. The statistical relationships of the parameters in the biosorption process by considering three controllable factors including initial pH value (2, 7, 12), initial dye concentration (25, 50, 75 mg L-1 ) and contact time (30, 150, 270 minutes) were investigated at three different levels and the biosorption process was optimized using Taguchi orthogonal array (L9 OA) experimental design. As a result of experimental studies, the optimal dye removal conditions were determined as the contact time of 270 minutes, pH: 2 and initial Bromophenol Blue concentration of 50 mg L-1 for F. fomentarius. The optimal dye removal conditions were determined as the contact time of 150 minutes, pH: 2 and initial Bromophenol Blue concentration of 50 mg L-1 for T. versicolor. For F. fomentarius and T. versicolor, the removal efficiencies at optimum conditions were 78.34% and 69.28%, respectively. Biosorption isotherms were modeled using the Langmuir and Freundlich models. The biosorption of Bromephenol Blue on F. fomentarius and T. versicolor fitted better in the Freundlich and Langmuir models by non-linearized equations, respectively. Both biosorbents can be promising for dyes removal from aqueous environment. [ABSTRACT FROM AUTHOR]

Heavy metal industries pose a serious threat to the environment. Conventional methods used for heavy metal removal are generally not always low-cost and environmentally friendly. So, researchers focused to investigate alternative biosorbents for the uptake of heavy metal. In this study, Laurus nobilis leaves (LNL) were used as a biosorbent for the uptake of toxic metals such as Pb2+ and Cd2+ from aqueous solutions. Batch biosorption experiments under varied conditions, such as biosorbent dosage, solution pH, heavy metal concentration, biosorption time, ionic strength, humic acid effect and competitive metal ions (Cd(II), Pb(II), Cu(II) and Zn(II)) were performed. The biomass was characterized using FT-IR spectra and SEM images. The nonlinearized and linearized isotherm models were compared and discussed. A single-stage batch bioreactor system for each heavy metal based on the best fit nonlinear isotherm model also has been presented. The biosorption of Pb(II) on LNL fitted better in the Langmuir model and Cd(II) biosorption fitted better in the Freundlich model by nonlinearized equations. The LNL exhibited the maximum monolayer biosorption capacities (qmax) of 7.1 and 32.5 mg/g for cadmium and lead, respectively. LNL showed great potential especially in Pb(II) uptake. LNL may be promising for heavy metal removal from aqueous environment. [ABSTRACT FROM AUTHOR]