Physical and chemical characteristics of wood ash

Published Date
Bioresource Technology
1991, Vol.37(2):173–178, doi:10.1016/0960-8524(91)90207-Z

• Author 

• L. Etiégni
• A.G. Campbell 

• Department of Forest Products, University of Idaho, Moscow, Idaho 83843, USA

Received 20 July 1990. Revised 10 October 1990. Accepted 16 October 1990. Available online 25 June 2003. 

Abstract

Chemical and physical properties are important in the development of processes for the disposal and utilization of wood ash. Ash yield was seen to decrease by approximately 45% as the combustion temperature increased from 538 to 1093°C. Potassium, sodium, zinc and carbonate content decreased with temperature, whereas other metal ions remained constant or increased. Wood ash leachate contained 92% hydroxide and 8% carbonate. The rate of ash leaching was rapid in an orbital shaker, and approximately 60% of the total potassium and sodium dissolved. The total dissolved solids increased by 500% as the pH decreased from 13 to 5. The ash had an average particle size of 230 μm. Scanning electron micrographs showed large porous carbon particles and inorganic particles which reacted with water to form clusters of rosettes. X-ray diffraction patterns suggested that calcium silicate hydrate may be responsible for some of the swelling that occurs when ash and water react.

Keywords

• Composition
• leaching
• SEM
• X-ray diffraction
• wood ash

---

• ☆
  Contribution from the University of Idaho Forestry, Wildlife and Range Experimental Station Paper No. 551

• ‡
  To whom correspondence should be addressed

For further details log on website :

http://www.sciencedirect.com/science/article/pii/096085249190207Z