安徽明光凹凸棒土盐酸改性前后的矿物学特征及其孔结构

MINERALOGICAL CHARACTERISTICS AND PORE STRUCTURE OF PALYGORSKITE PRE-AND POST-HYDROCHLORIC ACID MODIFICATION FROM MINGGUANG,ANHUI

为改善凹凸棒土的表面性能,提高其实用价值,采用6 mol/L的盐酸溶液对安徽明光凹凸棒土进行浸渍和离子交换处理。通过扫描电镜(SEM)、透射电镜(TEM)、傅立叶变换红外光谱(FT-IR)、X荧光光谱(XRF)、BET-比表面积分析(BET-SSA)及全孔分布等研究手段来观察凹凸棒土的改性效果,结果表明:盐酸改性处理可使凹凸棒土内部细长而致密有序的晶束被打断、破碎和分散,微晶表面粗糙度增大;杂质如钙、镁、锰被大量去除,这可能与这些杂质在凹土矿物中的存在形态有关;凹凸棒土的比表面积和总孔容积分别增至原来的2倍多和近2倍,中孔容积从0.092 cm3/g增加到0.148 cm3/g,而平均孔径从19.29 nm减小到16.46 nm。由此认为,经过6 mol/L的盐酸处理,改性凹凸棒土的性能得到了改善。

In order to amend the superficial performance of palygorskite and improve its applied value, natural palygorskite （NP） was treated in the dipping and ionic exchanging experiments using 6 mol/L hydrochloric acid in this paper. And the performance of the modified palygorskite（MP） was investigated by scanning and transmission electron microscopic, Fourier transform infrared, X-ray fluorescent, BET-specific surface area and full hole distribution analyses. The results showed that hydrochloric acid treatment can make the gracile and aggregating compact crystal bundles inside palygorskite clay broken and dispersed, and the roughness degree of microcrystalline surface increase; some impurities like Ca, Mg, Mn have been removed greatly, which may be related with the existential form of these impurities in palygorskite mineral; the specific surface area and the total pore volume（Vtotal） in MP are more than and close to twice the size of that in NP, respectively. The mesopore volume （Vmeso） increased from 0. 092 cm^3/g to 0. 148 cm^3/g, while the mean pore size decreased from 19.29 nm to 16.46 nm. It is indicated that the performance of MP has been improved a lot after 6 mol/L hydrochloric acid treatment.