METHOD FOR REMOVING AND RECOVERING METAL BY USING ROOT PART OF WATER HYACINTH

摘要

PURPOSE:To remove the metals in water efficiently and to recover the metals bringing drainage water, waste water and natural water contg. metals into contact with the root part of water hyacinth (eichhornia crassipes solms) then treating the root part of the water hyacinth with a dilute acid soln. CONSTITUTION:The root part of water hyacinth is used in the state of the selected moist root or after the root is thoroughly drained of water, the root is dried by ordinary natural drying or by drying with ventilated heating to form the dry root having about 10% moisture. A plastic net bag in which the root of the water hyacinth prepd. in the above-mentioned way is packed is charged into drainage water contg. metals. The bag is left to stand for a while and if necessary the water is stirred during this time to adsorb the metals in the water on the root part and thereafter the net bag packed therein with the root part is taken out. The root part is then washed with 0.1N hydrochloric acid soln. to liberate the adsorbed metals from the root part and to recover the same. The root part is washed to nearly neutral with water to regenerate the same and is reused for the adsorption and removal of the metals.