摘要
实验研究改进了测定矿物颗粒表面积的酸—碱滴定法，即应用改进ＢＥＴ方程求矿物颗粒的最大表面酸量（｛Ｍ＋｝Ｔ）和碱量（｛Ｍ－｝Ｔ），并分别用改进酸—碱滴定法和Ｎ２—ＢＥＴ方法测定了１２种矿物颗粒（３种粘土，８种氧化物和１种碳酸钙）的比表面积。结果表明，应用酸—碱滴定法不仅可得到合理的｛Ｍ＋｝Ｔ和｛Ｍ－｝Ｔ值，而且提高了测定表面积和相应酸度常数的准确性，由改进酸—碱滴定法得到的表面积平均比用Ｎ２－ＢＥＴ方法测得的表面积大一个数量级，且二者有显著的相关性。
The acid-base titration method for determining the surface area of mineral particulates is improved, where the modified BET equation is applied to estimate the maximum surface acid/base amount ({M+}/{M-}) by fitting the surface acid/base amount to /. Specific surface areas of 12 mineral particulates are determined by the improved method and by the N2-BET method. It is not only reasonable and accurate to obtain {M+}T or {M-}T by the modified BET equation, but also favourable to improve the accuracy of specific surface area and acidity constant. Specific surface areas determined by the improved acid-base method, SAB, are about one magnitude of order larger than those by the N2-BET method, SBET, and the relationship between SAB and SBET can be expressed satisfactorily by the equation: SAB=13.1SBET. The results show that SAB may reasonably reflect the specific surface area of mineral particulats in aqueous solutions, especially for marine sediments.
基金
国家自然科学基金
关键词
矿物颗粒
表面积
酸
碱
滴定法
mineral particulate
surface area
acid-base titration method
