Effects of Solvents on Synthesis and Dispersion of Zircon Powder via Non-hydrolytic Sol-gel Route

摘要

Zircon nano-powder has been synthesized via the non-hydrolytic sol-gel route, using industral zirconium tetrachloride (ZrCl_4) and tetraethoxysilane (TEOS) as precursors, lithium fluoride (LiF) as mineralizer, PEG 1000 as dispersant. The effects of solvents on the synthesis and dispersion of zircon nano-powder were investigated by means of XRD and TEM. The results indicate that the aprotic solvent N, N-dimethyl formamide (DMF) is not conducive to the nucleophilic substitution reaction, which directly affect the zircon synthesis, and the particles are easy to agglomerate due to the large surface tension; the powder with size of 30nm and good dispersion can be obtained using dichloromethane (CH_2Cl_2) as solvent; different anhydrous alcohols as solvents influence zircon synthesis, the order of the yield is listed as EtOH>propanol (PrOH)>isopropanol (Pr~iOH). Powder particles are larger than 50nm with wide distribution and serious agglomeration when taking PrOH and Pr'OH as solvents. Nano-zircon with good dispersion and yield up to 94.5% can be obtained via using ethanol as solvent.