ALTERNATIVES FOR THE REDUCTION OF CU(II) ION LEVELS IN HEMODIALYSIS MEMBRANES PRODUCED FROM SUGARCANE BAGASSE

The objective of the present study was to seek alternatives for the re duction of Cu(II) ion levels in hemodialysis membranes produced by the cuprammonium process. The alternatives used were: (a) replacement of the solvent Cu(NH3)(4)(OH)(2), used in the original process, with Cu(E DA)(2)(OH)(2), and (b) increasing the reflux time of the bagasse purif ication process from 1.5 to 3.0 h. The experimental results were obtai ned by analysis of Cu(II) content in the membranes by atomic absorptio n, by complexometry via UV/Vis spectroscopy of the solutions of filter paper, bagasse and lignin, and by monitoring the various stages of th e purification process (by FTIR and by loss of mass), i.e. pretreatmen t with 0.25 M NaOH followed by treatment with 4.2 M EDA and reflux wit h EtOH/HNO3 (20%, v/v). The results showed that the Cu(II) content in the membranes decreased with the use of the Cu(EDA)(2)(OH)(2) solvent, that the purification process could not be improved further since cel lulose degradation was observed, and that the Cu(II) content in the me mbranes produced was still to high for their use for hemodialysis trea tment.