Study on Influencing Factors of Swelling Properties of Bentonite

The basic physical and chemical properties of bentonite from Xiazijie,Xinjiang;Siping,Jilin;Anji,Si'an and Changshan,Zhejiang were tested,and their montmorillonite structures were analyzed.Based on the above,the authors discussed the relation between the montmorillonite content,the exchangeable cationic type between layer and its amount,the montmorillonite structure and the swelling performance of bentonite.The results indicated that:(1) the better swelling performance the higher montmorillonite content;(2) the exchangeable cationic type between layer has a great influence on the swelling performance of Na-bentonite strongly,and the swelling performance of Na-bentonite is superior to the Ca-bentonite;(3) the better swelling performance the lower layer charge of Na-bentonite,however the Ca-bentonite is reversed;(4) As to Na-bentonite,the swelling performance decreasing with the montmorillonite structure ordering,but to Ca-bentonite,the relation between the two is not obvious.