The study of recovery silver Nano-particles from the scrap with conductive silver paste

• Main Authors: Ming-Yu Han, 韓鳴宇
• Other Authors: Wen-Ching Say
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/n5yrcp

碩士 === 國立臺北科技大學 === 材料科學與工程研究所 === 101 === According to the lack of noble metal resource becomes a serious problem now; recycle is a good way to get noble metal such as gold, silver, platinum and etc. In this study, we recycle silver resource from conductive silver paste which is the main conductor of electricity in the membrane of keyboard. In this research, we want to get silver nanoparticles from this membrane; chemical reduction is a cheap and easy method to get silver Nano-particles. After thermal treatment at 600℃, almost all polymers are removed. Add nitrate into the silver crap then the solution becomes silver nitrate. By using chemical precipitation method, this research can get the silver chloride precipitation from the reactant including silver nitrate and chloride. This study uses different molar concentration of Ag(NH3)2+, NaBH4 and CTAB to find a proper proportion preparing silver nanoparticles. This study analyses the final product by using XRD, SEM, UV-Vis, EDS, and ICP-AES. The XRD result shows that this research can successfully get silver nanoparticles with crystal structure from conductive silver paste. The result of UV-visible spectrometer shows that a characteristic absorbance peak around 400 nm in wavelength can be found. The particle size is around 70nm when the molar ratio of NaBH4 / Ag is 1.5 and the molar concentration of CTAB is 20mM. The conversion rate is above 99%.