جستجوی مقالات مرتبط با کلیدواژه "color removal" در نشریات گروه "شیمی"

Vinasse is a well-known associate of sugar cane/beet ethanol production wastewater. In the present work, the electrocoagulation technique at a constant current intensity combined with circulation flow introduces as a new and economic method for the treatment of vinasse effluent using iron and/or aluminum without changing the initial conditions of sample solution. Spectrophotometric determination was used to quantify the COD and turbidity in effluents as the most regarded vinasse footprints. The proposed CCD method was used as an experimental design, having as independent variables, applied current, pH, electrode material, and the reaction time, evaluated for highest COD, turbidity, and color removal. The optimum conditions for removal of COD, color and turbidity determined by response surface modeling (RSM) showed that the proposed circulating electrocoagulation (CEC) method using aluminum-graphite electrodes at 1 A current, pH 7 and reaction time of 45 min is able to be used with high efficiency for the treatment of vinasse wastewater in ethanol production industry. The proposed method is very simple, cheap and fast and can be used as a pilot system in alcohol factories to recover the water which can, in turn, be utilized for agricultural purposes and other industries.

The removal of basic dyestuffs (Basic Red 46 and Basic Blue 41) from synthetic dye solutions was examined by using perfluorosulfonic acid-based polymer for the first time in the present study. The effects of four different variables, such as pHs (3.0, 5.0, 7.0, 9.0, and 11.0), temperature (25 °C, 35 °C, 45 °C, 55 °C, and 65 °C), initial dyestuffs concentration (20, 40, 60, 80 and 100 mg L-1) and treatment time (20, 40, 60, 80 and 100 min.) on the removal performance were investigated. The optimum conditions were determined for R46 as pH: 6.5; temperature: 54.1 °C; concentration: 97.4 mg L-1; time: 60.8 min. and for B41 as pH: 7.5; temperature: 54.6 °C; concentration: 67.1 mg L-1; time: 69.5 min. by using Response Surface Methodology. Removal performance values for R46 and B41 were determined respectively 99.9% and 99.5% at the optimum conditions. Also, perfluorosulfonic acid-based polymer was able to regenerate up to 20 cycles without significant performance change for the dyestuff removal process.

The color removal of three reactive dyes in an aquatic system without priortreatment was studied. Selected commercial dyes were treated with NaC102 andUV as oxidation agents. Effects of nature of oxidant, temperature, pH ofsolutions, concentration of C107—, contact time of C102— and UV irradiation wereinvestigated. Optimal C102— concentration for color removal in the absence of UVirradiation was found to be 20 mg I for all dyes studied. Combination of UVirradiation and C102— was found to be more effective. C102— dosage between 20mg I and UV irradiation (15 watts) for color removal than individual oxidantwith contact time of 30 minutes was required. The accuracy of method waschecked by measuring the COD of the samples. For determination of colorremoval of samples, Spectrophotometery method was used for measurement ofabsorbance changes of the samples (AA).