Method for preparing mullite crystal whisker by non-hydrolytic sol-gel process

The invention discloses a method of preparing porzite whiskers by a non-hydrolyzed sol-gel technology. The method comprises the following steps: using an anhydrous aluminum source and an anhydrous silicon source as precursors and using low-carbon alcohol or ether as an oxygen donor to prepare porzite xerogel powder; then adding a certain amount of fluoride as a whisker catalyst and calcining a closed crucible to prepare the high-purity and white porzite whiskers which have the diameter of 0.2 micron to 2 micron, a slenderness ratio up to 60 to 70 and do not comprise mingled particles. Compared with the prior art, the invention has the advantages of simple technology, convenient operation, low whisker preparation temperature and high whisker yield.