Application of Carbon-loaded Polyurethane Foam Produced by Ethanol Media in Determination of Gold in Geological Samples

Abstract

BACKGROUND Compared with unloaded polyurethane foam, carbon-loaded polyurethane foam can effectively increase the adsorption capacity of gold, but the existing preparation method of carbon-loaded polyurethane foam is not efficient. OBJECTIVES To shorten the preparation time of carbon-loaded polyurethane foam, improve the preparation efficiency, and optimize experimental conditions. METHODS Activated carbon-ethanol solution was used to prepare carbon-loaded polyurethane foam. By optimizing conditions such as the load medium type, reagent concentration, and soaking time, the time for preparing 100 carbon-loaded polyurethane foams can be reduced to under 30 min. A method for the determination of gold in geological samples by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) combined with carbon-loaded polyurethane foam is described. RESULTS The experimental results show that the oscillation time can be shortened to 20 min. The mass concentration of gold has a good linear relationship with the spectral intensity in the range of 0-100 μg/mL with the correlation coefficient of 0.9997. The detection limit (3σ) is 0.0066 μg/g, and the relative standard deviations of the results are 0.81%-2.11% (n=10). CONCLUSIONS Four certified reference materials of gold ore are used to evaluate the method. The results show good accuracy and precision, and the method meets the requirements of geological sample analysis.

Keywords

• geochemical samples
• gold
• carbon-loaded polyurethane foam
• the preparation efficiency
• inductively coupled plasma-optical emission spectrometry