Abstract: The effects of different particle size purified tourmaline powder samples on the filtration performance of air filter materials from Xinjiang， Hebei and Guilin were studied. Electrode performance of various tourmaline powder samples was carried out by piezoelectric experiments and pyroelectric experiments to identify the preferred polarization characterization. The results show that the electrode of the 0.074mm pure grade tourmaline has the best performance. The highest grade of three tourmaline powders is attached to the filter surface for the whole dust efficiency experiment. The 0.074mm pure grade of tourmaline in Guilin has the highest filtration efficiency. The most significant improvement is obtained. Using the Rietveld method， the XRD pattern of tourmaline powder is refined to obtain the crystal structure. The calculation of the intrinsic electric dipole moment proves that the electrostatic adsorption caused by the spontaneous polarization of tourmaline is the main reason for improving the filtration performance of the filter material.

Key words: tourmaline, spontaneous polarization, filtration efficiency, electric dipole moment, identification