การควบคุมขนาดผลึกของผงเงินโดยกรรมวิธีรีดักชันโดยใช้กลีเซอรอลผสมโซดาไฟ

• Main Author: โกเมน หมายมั่น
• Other Authors: เอกสิทธิ์ นิสารัตนพร
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2007
• Subjects: ผลึก; เงิน > การควบคุมการผลิต; กลีเซอรีน; โซเดียมไฮดรอกไซด์; Crystals; Silver > Production control; Glycerin; Sodium hydroxide
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:44685
• Institution: Chulalongkorn University

This research was to study the particle size of silver powder by reducing with glycerol from AgNO[subscript 3] 10, 20, 30 and 40g. Testing started at room temperature and increase temperature to 190 degrees celsius. The effect of adding sodium hydroxide was observed, the solution mol ratio between silver nitrate and sodium hydroxide is 1:2, 1:1, 1:0.5, 1:0.25 and 1:0.1. The temperature was varied between 30, 80, 100, 120 and 140 degrees celsius and the solution was stirred at 1000 rpm, The holding times of reduction were 30, 60, 90 and 120 minutes. The average particle size of silver powder using only glycerol is 0.5-5 [mu]m. Therefore the silver powders are large size and the powder shape is polygonal. In addition, the silver powder was agglomerate. This process a difficulty to control particle. By the usage of NaOH, NaOH affected to a decrease the reducing temperature as low as 30 degrees celsius. The silver powders are more spherical shape and has average size at 0.175 [mu]m. In creasing in temperature in the range of 80, 100, 120 and 140 degrees celsius decreased the particle size to 0.259, 0.212, 0.193 and 0.132 [m]m. respectively. However at silver particle has small size with 0.175 [mu]m. due to glycerol viscosity. Temperature afferted in size distribution of NaOH reduced silver particles, at 30 degrees celsius resulted in small silver particles size and low size distribution compared with the temperature of 80 degrees celsius. At highest temperaure, Ie.140 degrees celsius gives narrowest particles size distribution and also the smallest silver particle which is 0.132 micron.