Muthanna Journal of Pure Sciences
MJPS
Volume 3 issue 1, 2016
Abstract
This research is including of a new polymer from reaction between poly vinyl alcohol and acryl amide then study some of it's physical properties also study thermodynamic adsorption for aniline blue dye on polymer surface. The raw materials used in our experiments are available as commercial products. PVA, AM ,benzoyl peroxide, potassium persulfate, ferrous sulfate and ethylene glycol were used without further purification. The synthesis of polymer was done in aqueous solution and in ethylene glycol /water mixture (70/30). To determine the synthesis condition, took gravimetric ratio PVA, AM and benzoyl peroxide or redox system (potassium persulfate /ferrous sulfate as initiators were used. PVA was dissolved in water or ethylene glycol/ water mixture at (60-70)C°, solution were obtained, then the adequate quantity of acryl amide and initiator were introduced under continuous stirring in reaction vessel. Further, the temperature was raised and maintained at 85-90C° for 5 hours. The obtained products were dried at 60C° for 72hours to avoid hydration. The evidence of grafting was obtained by comparing FTIR spectra analysis of PVA, AM and grafted polymer as shown in section three . Adsorption studies were carried out to investigate the effect of different parameters such as: (contact time, adsorbent weight, pH, initial dye concentration and temperature effects). The results showed that the adsorption of anilin blue dye at initial concentration (30 ppm) was rapid at the first minutes of contact time until reached to the equilibrium time at (30)min for polymer. This percent removal (20ml) of anilin blue was at the equilibrium time for all the adsorbent also at the optimum weigh which were (0.9)g for polymer. The equilibrium adsorption isotherm has been examined by applying the Langmuir and Frendlich isotherms. The optimum experimental results were described by the frendlich isotherm. Thermodynamic parameters such as the change of free energy, enthalpy and entropy were also evaluated. The results indicated that the adsorption of the anilin blue dye onto the polymer was an endothermic, decrease disorder and spontaneity of the adsorption process.
Keywords: Poly vinyl alcohol, Thermodynamic adsorption, PVA