recovery of gold nanoparticles from electronic solid waste: an experimental design and mathematical approach

Due to the growing consumption of gold metal and its various applications, gold recovery is very important. the element gold is an electron-bearing particle that can be used in a variety of applications such as medicine, engineering, and biology by changing its surface activity and particle size. the purpose of this study is to recover gold metal in the form of gold nanoparticles from electronic solid waste. for this purpose and to better investigate the effect of factors affecting the extraction of gold nanoparticles, the response method has been used in the experimental design. the innovation is to make gold nanoparticles with the smallest particle size with the help of reducing materials and in a cost-effective way while saving energy and also the highest recovery rate. in order to make gold nanoparticles, there are different methods such as physical, chemical and biological methods. among these three methods, the use of the chemical method has been selected for this research. the material for extraction was royal acid, and parameters such as ph, the amount of royal acid and the temperature of the solution on the gold extraction efficiency were examined. the final nanoparticles were analyzed using xrd, fesem, edx and tem analyzes. in order to determine the effectiveness of each variable and to determine which of the studied variables has the greatest impact on the gold recovery process, statistical methods were used. the variables of ph, solution temperature and the amount of soltani acid had the greatest effect on the recovery of gold nanoparticles, respectively. according to the information obtained from design-expert software, at a temperature of 60°c and a ph of 8 and 200 ml of soltani acid solution, the recovery rate of gold nanoparticles was 97.3%.