Assessment of the banana pseudostem as a low-cost biosorbent for the removal of reactive blue 5G dye.

In this work, the removal of reactive blue 5G (RB5G) dye using the drying biomass of banana pseudostem (BPS) was investigated. The characterization of BPS particles was performed. Improvement in the RB5G dye removal performance at the following sorption conditions was evidenced: pH 1, 30°C sorption temperature and 40 rpm shaking, regardless of the particle size range. Kinetic RB5G dye sorption data obtained at better conditions fit well in an Elovich model. A combined Langmuir-BET isotherm model provides a good representation of the RB5G dye equilibrium sorption data, which shows the evidence of a physical sorption process on the BPS surface. Based on the results, the removal of RB5G dye molecules by BPS is based on a physical sorption process.

Electrocoagulation efficiency of the tannery effluent treatment using aluminium electrodes.

An electro-coagulation laboratory scale system using aluminium plates electrodes was studied for the removal of organic and inorganic pollutants as a by-product from leather finishing industrial process. A fractional factorial 2(3) experimental design was applied in order to obtain optimal values of the system state variables. The electro-coagulation (EC) process efficiency was based on the chemical oxygen demand (COD), turbidity, total suspended solid, total fixed solid, total volatile solid, and chemical element concentration values. Analysis of variance (ANOVA) for final pH, total fixed solid (TFS), turbidity and Ca concentration have confirmed the predicted models by the experimental design within a 95% confidence level. The reactor working conditions close to real effluent pH (7.6) and electrolysis time in the range 30-45 min were enough to achieve the cost effective reduction factors of organic and inorganic pollutants' concentrations. An appreciable improvement in COD removal efficiency was obtained for electro-coagulation treatment. Finally, the technical-economical analysis results have clearly shown that the electro-coagulation method is very promising for industrial application.