Study of the Agitation Effect on Optimizing the Scale-up Production of Nanosized Silver Particles

• Main Authors: Wen-Nung Lu, 呂文濃
• Other Authors: Jyh-Shyong Chang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/zb39hd

碩士 === 大同大學 === 化學工程學系(所) === 95 === Optimization on the synthesis of nanosized silver particles (Chang et al. 2007) by chemical reduction using formaldehyde in aqueous solution was carried out based on the laboratory experimental data (loading 100 cc reacting mixtures in a 250 cc beaker and shaking in an isothermal shaker). Effects of the possible processing variables such as the reaction temperature T, the mole ratios of [Formaldehyde]/[AgNO3] and [NaOH]/[AgNO3], PVP/AgNO3, and the molecular weight of protective agent PVP (polyvinyl-pyrrolidone) were considered. The colloid dispersion products were mainly characterized for its mean particle size and conversion of silver nitrate. The identified model based on the 44 designed experiments can provide us the optimal conditions for achieving different targets (Chang et al. 2007). In this study, we evaluated the feasibility of achieving the same targets by applying the optimal conditions cited by Chang et al. (2007) to the scale-up production (2 liters or more) of nanosized silver particles but varying the rotational speed of the impeller. From the seven experiments carried out, the particle diameter size 30.96 nm with conversion 38.4% was achieved at the rotational speed of the impeller 616 rpm (adopting the optimal conditions for achieving the minimum mean particle size 28.63nm with conversion 47.94% cited in Chang et al. (2007)). Similarly, the particle diameter size 35.69 nm with conversion 85.3% was achieved at the rotational speed of the impeller 616 rpm (adopting the optimal conditions for achieving mean particle size, 32.66nm with a desired conversion, 85% cited in Chang et al. (2007)). In this case study, by an increased rotational speed of the impeller (700rpm), a higher conversion can be achieved without sacrificing the mean particle size of the product.