我国叶蜡石的应用进展

PROGRESS ON UTILIZATION OF PYROPHYLLITE

叶蜡石是一种含水的铝硅酸盐,在加热过程中脱水,同时伴随体积膨胀,在高温下分解产生莫来石和石英。常常利用叶蜡石的体积膨胀,将其作为原料添加到制品中,抵消某些基体材料的收缩或者制品的烧成收缩,使制品具有良好的体积稳定性等特点。叶蜡石还具有熔点高,在高温下不收缩,化学性能稳定,无毒,耐腐,在水中无膨胀性和可塑性,良好的耐热隔热性、电绝缘性、传压性、机械加工性和密封性,具有低烧结温度、低电传导性、低膨胀系数等特点,是一种重要的电子、光学和结构材料,被广泛应用于冶金、建材、石油、化工、轻工等领域。将叶蜡石作为原料添加到耐火材料、陶瓷等制品中,一方面可以提高制品的使用性能,延长制品的使用寿命,另一方面也可以替代某些价格较高的原料,降低制品的成本,两者均可产生显著的经济效益。对叶蜡石的研究不但具有学术价值,而且还会带来经济价值。根据近年来叶蜡石在耐火材料、陶瓷、传压密封介质、玻璃纤维、橡胶、吸附剂、原料合成等领域应用的相关报道文献加以汇总,系统地总结了叶蜡石矿物材料的综合利用进展情况。

Pyrophyllite is a hydrous aluminum silicate and dehydrates during heating with volume expansion at the same time and it can be decomposed to 3A12O3 · 2SiO2 and SiO2 at high tem perature. Pyrophyllite with a certain volume expansion is usually used as a raw material added into products to offset the shrink caused by matrix or sintering, so the products with pyrophyllite have stable high volume. Pyrophyllite are also characterized by high melting point, no shrinkage at high temperature, chemical stability, non-toxic, crossion resistance, no swelling and plasticity in water, good heat insulation,good electrical insulation, good capability of passing pressure, good machin- ability and tightness,low sintering temperature, low electrical coductivity, low thermal expansion coefficient, etc. Also, pyrophyllite is an important electronic, optical and structural material, widely used in the field of metallurgy, building materials, petroleum, chemical, light industry, etc. The addition of pyrophyllite into refractories and ceramics as a raw material can improve the service life of products and reduce the prime cost. According to the newest investigation and study of pyrophyllite used in the aspects of refractories, ceramics, pressure and hermetical-medium, fiber glass, rubber, absorbent, synthesis of raw material, the progress on utilization of pyrophyllite is systematically introduced and reviewed in this paper.