Liquid Phase Pulsed Discharge as a Chemical-Free Green Method for [alpha]-Alumina Synthesis

• Published in: Plasma processes and polymers Vol. 13; no. 11; p. 1061
• Main Authors: Yang, Jason Hsiao Chun, Liao, Guan-Yu, Fujiyama, Hiroshi, Wu, Shinn-Dar, Yang, Chao-Chen
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 01.11.2016
• Subjects: Alumina; Aluminum; Chemical industry
• ISSN: 1612-8850; 1612-8869
• DOI: 10.1002/ppap.201600028

Green synthesis is a substantial method that meets today's industrial standard of lessened chemicals in the synthesis process. In the present study, submicron aluminum hydroxide (Al(OH)3) powders were synthesized from high purity aluminum rods (5N) and high purity aluminum flakes (4N) in an ultrapure water bath with a controllable duty cycle ([theta]) and pulse period (τ) discharge apparatus. The obtained aluminum hydroxide was then thermally decomposed to form [alpha]-alumina. Results show that high-yield production of aluminum hydroxide with larger crystalline size can be obtained by increasing duty cycle and pulse period. Similar outcome can also be achieved by increasing the weight of the aluminum flakes or extending the distance between the aluminum electrodes. In addition, [alpha]-alumina can be obtained at higher calcining temperature of 1200°C with extended holding time of 1h.