a process for recovery of gold from an impure precious and base metal-bearing acidic chloride or mixed chloride/sulphate solution comprises the steps of contacting the acidic solution with a polymeric acrylic ester adsorbent ion exchange resin to selectively adsorb gold, and stripping the gold from the loaded resin by elution with water.
among the most effective processes for the recovery of precious metals, specifically, gold is the use of activated carbon. activated charcoal in gold recovery when gold is dissolved in a cyanide solution, the best way to recover it is through the use of activated carbon, which is a viable alternative to the use of zinc.
the amount of gold adsorbed on ac increased as the adsorbent dosage concentration was increased from 1 to 4 g in all the samples. as the ac dose was increased, free sorption surface and adsorption sites also increased leading to greater adsorption of gold ions on the surface liu et al., 2010 .
gold-only removal without copper adsorption is obtained using oms-nh 2 adsorbent. more than 90 % of the gold is adsorbed from the solution as shown fig. 1e, and the removal efficiency reaches 100 % for solutions with dilute gold concentration making it an attractive adsorbent for gold recovery from dilute mining and recycling wastes. the
azerbaijan. in most cases, the choice of adsorbent was forced by the complex nature of the ore which made the use of activated carbon uneconomical. the main advantages of using resin over carbon are: improved gold recoveries from preg-robbing ores; better selectivity for gold over base metals, including copper;
pristine macadamia nutshell-based activated carbons were chemically oxidized with different concentrations of h 3 po 4 and hno 3 to increase their surface adsorption properties and further explore if they could be an attractive alternative low-cost adsorbent for gold recovery from cyanide-leached liquors. the modified activated carbons were labeled macn 20, macn 40 and macn 55 to signify the
gold recovery activated carbon has long been used as an adsorbent in the gold processing industry to recover gold from mining operations. due to its high surface area and exceptional hardness, coconut shell gac granulated activated carbon is the main product used in carbon-in-leach cil , carbon-in-pulp cip , and carbon-in-column cic operating systems.
3.3. gold recovery from 0.1 and 1 ppm and 1 ppt seawater. for the seawater sample with 0.1 and 1 ppm added gold, we find that the adsorbent was equally effective over 95% recovery rate with the exception that up to 18 h of suspension was required for full recovery of the gold.
gold 1 100 mg/l in the lixiviant means that an adsorbent, particularly nanomaterials at the atomic level with higher surface area, need to be further developed in order to enhance the recovery of chemicals or contaminants in aqueous phases by adsorption processes 8,9 .
recovery of gold from aqueous solution containing au iii by silicon organic polymer 16 the main objective of this work was to evaluate the au adsorption capacity of synthesized psot-3 from aqueous solution with au iii depending on varying concentration of hydrochloric acid solution, agitation time, initial concentration of au iii and temperature.
activated carbon has been proven to be an effective adsorbent for the recovery of a wide variety of metal ions from aqueous solutions. in this research, the activated hard shell of iranian apricot stones was used for gold recovery from electro-plating wastewater.
the fine adsorbent which is recovered contains some gold that was loaded in the adsorption circuit. carbon losses can vary from 10 to 60 g/t of processed ore. this carbon can contain from 100 g to 1500 g of gold per ton. gold recovery from carbon fines is normally done by combustion followed by cyanidation of the ash.
the gold recovery efficiency for all adsorbent weights used and this is in line with previous observations for other modified cellulose adsorbents for au iii adsorption available in the
experimental studies indicated high maximum adsorptions of gold as high as 99.9% recovery. another promising attribute of these materials is their favourable adsorption kinetics. the mp-hms reaches equilibrium saturation in less than 1 minute of exposure in gold bromide and less than 10 minutes in gold chloride.
activated carbon has been the preferred adsorbent for gold recovery in the western world for the past few decades. contrastingly, former soviet union fsu countries have always preferred ion exchange resins, mainly employing resin-in-pulp rip technology 1 . ion exchange resins have
gold recovery via conventional processes, but it appeared that a degree of preg-robbing occurred during repulping and that some gold was lost. in order to prevent these gold losses, it was proposed that an adsorbent-in-solution process be employed to recover the gold from the milling-in-cyanide solution prior to using it for repulping.
chitosan-coated magnetic nano-adsorbent was prepared according to our previous work 22 . fe 3 o 4 nanoparticles were prepared by co-precipitation method and chitosan was carboxymethylated. for the binding of carboxymethyl chitosan, 100 mg of fe 3 o 4 nanoparticles were first added to 2 recovery of gold iii ions by a chitosan-coated magnetic nano-adsorbent