nanovlákna --- nanotechnologie --- elektrostatické zvlákňování --- spektrofotometrie --- textilní chemie

The release of dyes into the environment only contributes a small proportion of water pollution but due to dye brilliance, they are visible even in very small quantities such that the control of water pollution has become of high importance nowadays. Government legislations are therefore forcing dye using industries to treat their effluent to high standards. Colour removal by conventional treatment methods such as ozonation, bleaching, hydrogen peroxide/UV, electrochemical techniques are not adequate due to the fact that most textile dyes have complex aromatic molecular structures that resist degradation. The research has shown that the use of membrane filtration can be an alternative for low cost treatment methods. In this study membrane made of electrospun polyamide 6 nanofibres is used in order to investigate the effects of increasing temperature on dye removal (sorption) using sorption filtration method. C.I Acid blue 41, C.I Acid yellow 42 and C.I Acid blue 78 were used to determine the accumulated mass of each on the electrospun polyamide 6 nanofibre membrane, using the temperatures of between 20 °C and 60 °C. The accumulated mass could decrease with the increase in temperature till the glass transition temperature of the membrane such that above this temperature the accumulation of dye was increased. All the results were based on spectrophotometric analysis and also the SEM was used for image analysis in order to analyze the effects of increasing temperature on the surface of the membrane. All the dyes tested could follow the Langmuir isotherm such that the curves for the experiments and the ones for Langmuir isotherm were comparable with very small differences. The results also show that C.I Acid Blue 41 had the highest values of sorption capacity compared to Acid Blue 78 and Acid Yellow 42, this was because of the highest saturation value (S) compared to the other two. Determination of sorption capacity at equilibrium was tested after a period of 10 days with increasing mass of fibre from 1 piece up to 10 pieces of 30mm x 30mm nanofibrous membrane with constant concentration and volume of solutions used.

Effects of temperature on sorption process using nanofibrous membrane