Recovery of cutting liquid by membrane filtration and separation of silicon and silicon carbide using a modified settling unit

• Main Authors: Sheng-Yang Ho, 何昇陽
• Other Authors: 蔡子萱
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/v3n3sh

碩士 === 國立臺北科技大學 === 資源工程研究所 === 100 === In silicon wafer manufacturing, a large amount of slurry waste is produced and feedstock is wasted during cutting process. Recovery of silicon carbide, cutting liquid and kerf silicon will be a good solution to reduce waste and costs. This study investigated recovery of cutting liquid from the silicon slurry waste by membrane filtration, and separation of silicon and silicon carbide using a modified settling unit. The experimental results show that the solid content in the feed is the most important factor for increase the filtration flux. It was found the input rate 134ml/min for slurry waste with 50wt%water at 105KPa resulted in good separation performance. Its recovery yield reached 81.69%. In addition, the important properties of the recovered liquid are similar as the original cutting liquid. The experimental results for the separation of silicon and silicon carbide show at pH 7 and the ionic strength 0.01M, the SiC content of the recovered silicon carbide could increase to 95wt.% using settling unit CM-U, the SiC content of the recovered silicon decreased to 9wt.％, and the metal content of the recovered silicon decreased to 2636ppm. Moreover, the recovery of silicon and silicon carbide with our modified settling unit (C) can save time, and iron were removed 52.07% at the same time.