Removal of chromium ions (VI) from underground water in the hybrid complexation-ultrafiltration process

Transport and separation properties of ultrafiltration membranes made from polyacrylonitrile have been characterized and their suitability for chromiu m ion (VI) removal from underground water by means of complexed hexadecylpy ridine chloride has been evaluated. It has been found that membranes of a 1 7.5% polymer content retain 98% of the chromium complex (VI) while the rema ining ions present in water pass to the permeate. Tests which aimed at dete rmining the most favourable amount of a complexing substance in relation to the amount of chromium ions (VI) and the optimum pH of the solution for wh ich a retention coefficient of the chromium complex (VI) was the highest ha ve been conducted. The results obtained confirmed that the complexation-ult rafiltration system presents an effective method for chromium ion (VI) remo val from abyssal water.