THE AIM OF THE PRESENT PROPOSAL IS TO DEVELOP NEW RECOVERY METHODS OF PRECIOUS METALS (MAINLY AG, AU, HG, PD, PT) FROM SOLUTIONS BY FIXATION ON INORGANIC SOLIDS (INORGANIC FIXATORS). THE PARTICLES OF THE SOLID MAY BE PLACED IN THE SOLUTION AND FILTERED AFTER THE FIXATION OR THEY MAY BE PLACED IN A COLUMN THROUGH WHICH THE SOLUTION IS POURED. TESTS ON INDUSTRIAL WASTES BY THE DEVELOPED METHOD MAY PROVE THE PRACTICAL APPLICABILITY.
Precious metals can be recovered from industrial waste solutions by pouring the solution through a column of a selected inorganic solid.
Investigations performed have included:
a systematic study of the rate of fixation of precious metals on precipitated solids (cyanocomplexes and sulphides);
determination of sorption parameters in batch and column experiments;
preparation of column packings using an inert carrier material impregnated with the inorganic sorbent;
development of techniques to produce sorbents of controlled grain size which can be used in columns without a carrier;
study of the mechanisms of fixation;
study of the influence of other elements on fixation (a situation which would be found in real waste solutions).
Inorganic sorbents have been selected for each of the metals silver, palladium, gold, mercury and platinum, and a mixture of sorbents can be used to collect several noble metals simultaneously.
1. EVALUATION OF TYPICAL INDUSTRIAL WATERS : NOT ONLY THE PRECIOUS METALS WILL BE DETERMINED BUT ALSO OTHER ELEMENTS COULD INTERFERE IN THE SEPARATION.
2. DEVELOPMENT OF ANALYTICAL METHODS : ANALYTICAL METHODS WILL BE ADAPTED OR DEVELOPED FOR THE EVALUATION OF WASTES AND FOR THE DETERMINATION OF FIXATION RATE ON INORGANIC FIXATORS. THE MAIN METHODS WILL BE ATOMIC ABSORPTION SPECTROMETRY IN RUB AND CECM, ACTIVATION ANALYSIS AND RADIOACTIVE TRACERS IN CECM, INDUCTIVELY COUPLED PLASMA ATOMIC EMISSION SPECTROMETRY (ICP/AES) IN RUB.
3. SEPARATION OF SILVER AND PALLADIUM ON A COLUMN OF FERRO OR FERRICYANIDES.
4. FORMATION OF FERRO OR FERRICYANIDES IN SITU WITH FIXATION OF SILVER AND PALLADIUM.
5. PREPARATION AND STUDY OF INSOLUBLE CYANIDES AND SULPHIDES USED AS INORGANIC FIXATORS.
6. PREPARATION OF POROUS CARRIERS.
7. SEARCH OF OTHER INORGANIC FIXATORS.
8. OPTIMIZATION OF PROCEDURES.
Funding SchemeCSC - Cost-sharing contracts