Spectrophotometric Determination Of Trace Copper And Gold In Ore Samples After Separation Preconcentration With Ion Exchange Resin

The optimization of the condition of mineral processing production and floating agent, flotation effect can be realized by way of analysis and testing. During the flotation of copper and gold molybdenum, the content of trace copper and gold in molybdenumconcntrate, milltailings and gold ore must be exactly understood. Adsorption and desorption properties were investigated with Cu2+ and Au3+ on 732 cation exchange resin and 717 anion exchange resin respectively. The influence of adsorption and desorption properties for PH value, flow rate, eluent, and coexisting ions et al was analyzed.The method of ion exchange resin separation and enrichment-spectrophotometry to measure trace copper of molybdenum concertrate and tailings of copper and trace gold of gold mine was established. The concrete research methods and results are as follows:1. Trace copper of molybdenum concertrate and tailings analysis1) The adsorption and desorption of copper was determined by spectrophotometry:neocuproine was deoxidated by hydroxylamine hydrochloride to analyse copper by spectrophotometry, the maximum absorption wavelength is 457nm, standard working curve equation is A=0.1186C+0.0016, correlation coefficient is r=0.9996.2) 732 cation exchange resin was been pretreated and determinated the parameter to get resin all exchange capacity:3.52 mmol/g; the adsorption capacity on copper is 207.9 mg/g.3) Static adsorption optimal conditions:adsorption time 60 min, PH=54)Dynamic adsorption and elutionrequirement:upper prop solution PH=4-7, flow rate of upper prop solution is 1mL/min, eluent is 3mol/L(HCL), flow rate of eluent is 0.33mL/min, 10mL HCL solution can achieve quantitative elution effect.5) In the best dynamic separation and enrichment experimental conditions, the incoming sample volume is 300 mL, enrichment multiples is 30; spike recovery, precision testing and detection limit determination result pointed out:recovery of this method is 95-108%, precision RSD%=4.5%(n=7), LOD=0.75μg/L.The results of this method for determining trace copper of molybdenum concertrate and tailings are compared with the results of atomic absorption spectrum method, and the results are basically the same. The results show that the mentioned method which possesses high sensitivity, good selectivity and repeatability can meet the practical ore samples analysis.2. Trace gold of gold ore analysis1) The adsorption and desorption of gold was determined by spectrophotometry: gold was determined by crystal violet color development spectrophotometry, the maximum absorption wavelength is 600nm, in the best color development conditions experiment, the adsorption influence of extraction time and PH were investigated, optimal conditions:extraction time is 1.5min,PH=1.4 and standard working curve equation is A=3.9786C+0.0199, correlation coefficient is r=0.9961.2) 717 anion exchange resin was been pretreated and determinated the parameter to get resin all exchange capacity:2.16 mmol/g; the adsorption capacity on gold is 178.6mg/g.3) In the static adsorption experiment, the adsorption influence of extraction time and PH were investigated, optimal conditions:extraction time is 60 min,10% hydrochloric acid solution4) Dynamic adsorption and elutionrequirement:upper prop solution 10% hydrochloric acid, flow rate of upper prop solution is 1mL/min, eluent is 6% sulfourea solution, flow rate of eluent is 0.4 mL/min,10 mL sulfourea solution can achieve quantitative elution effect.5) In the best dynamic separation and enrichment experimental conditions, the incoming sample volume is 300mL, enrichment multiples is 30; spike recovery, precision testing and detection limit determination result pointed out:recovery of this method is 95-109%, precision RSD%=3.6%(n=7), LOD=0.43μg/L.The results of this method for determining trace copper of molybdenum concertrate and tailings are compared with the results of activated carbon adsorption method, and the results are basically the same. The results show that the mentioned method which possesses high sensitivity, good selectivity and repeatability can meet the practical ore samples analysis.