钠硼解石——水体系溶解和相平衡的研究(英文)  

Study on Dissolution and Phase Equilibrium in Ulexite-water System

作　　者：陈若愚[1] 高世扬[2] 冯守华[3] 夏树屏[2] 陈正隆[4] 

机构地区：[1]江苏工业学院化学工程系,常州213016 [2]中科院盐湖所西安二部,西安710043 [3]吉林大学水热合成实验室,长春130023 [4]台湾中山大学化学系,高雄80424

出　　处：《无机化学学报》2004年第7期812-818,共7页Chinese Journal of Inorganic Chemistry

基　　金：国家自然科学基金资助项目(No.29971032)。

摘　　要：Ulexite dissolution in water has been studied in the wide temperature range from 10℃ to 93 ℃ and two higher temperatures at 120 ℃ and 240 ℃. The analytical results showed that ulexite dissolved congruently from 10 ℃ to 35 ℃ and incongruently from 40 to 68 ℃. The solid component of ulexite, NaCaB5O6(OH)6·5H2O was dehydrated to form NaCaB5O6(OH)6·H2O from 50 to 68 ℃ and finally amorphous solid at 68 ℃. This amorphous solid converted into priceite at 71 ℃ and then converted completely to priceite at the boiling point(93 ℃) of the solution. At both 120 and 240 ℃, the dissolution of ulexite was an incongruent process. Above 120 ℃, ulexite became amorphous solid and then transformed into priceite. In addition to the solid to solid transformation, crystallization of priceite from the solution has also been observed. Based on our experimental results, mechanisms of dissolution, transformation, and crystallization of borate in ulexite-water system are discussed.Ulexite dissolution in water has been studied in the wide temperature range from 10℃ to 93 ℃ and two higher temperatures at 120 ℃ and 240 ℃. The analytical results showed that ulexite dissolved congruently from 10 ℃ to 35 ℃ and incongruently from 40 to 68 ℃. The solid component of ulexite, NaCaB5O6(OH)6·5H2O was dehydrated to form NaCaB5O6(OH)6·H2O from 50 to 68 ℃ and finally amorphous solid at 68 ℃. This amorphous solid converted into priceite at 71 ℃ and then converted completely to priceite at the boiling point(93 ℃) of the solution. At both 120 and 240 ℃, the dissolution of ulexite was an incongruent process. Above 120 ℃, ulexite became amorphous solid and then transformed into priceite. In addition to the solid to solid transformation, crystallization of priceite from the solution has also been observed. Based on our experimental results, mechanisms of dissolution, transformation, and crystallization of borate in ulexite-water system are discussed.

关 键 词：钠硼解石 水体系 溶解 相平衡 相转化 

分 类 号：O614.112[理学—无机化学] O613.81[理学—化学]