应用化工
應用化工
응용화공
APPLIED CHEMICAL INDUSTRY
2014年
7期
1276-1281
,共6页
王玉雪%谢放华%李妲丽%陈春燕%吕宪伟%陈掌%宁文博
王玉雪%謝放華%李妲麗%陳春燕%呂憲偉%陳掌%寧文博
왕옥설%사방화%리달려%진춘연%려헌위%진장%저문박
双乙酸钠%结晶%溶解度%介稳区%改进Jouyban-Acree模型
雙乙痠鈉%結晶%溶解度%介穩區%改進Jouyban-Acree模型
쌍을산납%결정%용해도%개은구%개진Jouyban-Acree모형
sodium diacetate%crystallization%solubility%metastable zone%the modified Jouyban-Acree model
为提高双乙酸钠( SDA)的产品质量,考察了温度、溶剂组成、乙酸钠含量等条件对SDA溶解性的影响,采用动态法测定了SDA在不同质量分数乙醇-水、乙酸钠-水混合溶剂中的溶解度,并测定了SDA在纯水和质量分数为0.7996(w1=0.7996)的乙醇溶液中的介稳区。结果表明,SDA易溶于水,微溶于乙醇,随乙醇质量分数增加,SDA溶解度降低愈加显著,且在w1=0.7996的乙醇溶液中降低最为明显;随产物中乙酸钠含量增加,SDA溶解度逐渐减小,且在质量分数为0.0832乙酸钠溶液中降低幅度最大;在300~315 K范围内,w1=0.7996的乙醇溶液对SDA和乙酸钠有明显的分离效果;SDA的介稳区宽度在纯水中随温度升高逐渐变窄,而在w1=0.7996的乙醇溶液中受温度影响变化小,且介稳区宽度较纯水中窄。因此,在SDA结晶中,可采用w1=0.7996的乙醇溶液结晶分离SDA,且过饱和浓度需控制在介稳区内。
為提高雙乙痠鈉( SDA)的產品質量,攷察瞭溫度、溶劑組成、乙痠鈉含量等條件對SDA溶解性的影響,採用動態法測定瞭SDA在不同質量分數乙醇-水、乙痠鈉-水混閤溶劑中的溶解度,併測定瞭SDA在純水和質量分數為0.7996(w1=0.7996)的乙醇溶液中的介穩區。結果錶明,SDA易溶于水,微溶于乙醇,隨乙醇質量分數增加,SDA溶解度降低愈加顯著,且在w1=0.7996的乙醇溶液中降低最為明顯;隨產物中乙痠鈉含量增加,SDA溶解度逐漸減小,且在質量分數為0.0832乙痠鈉溶液中降低幅度最大;在300~315 K範圍內,w1=0.7996的乙醇溶液對SDA和乙痠鈉有明顯的分離效果;SDA的介穩區寬度在純水中隨溫度升高逐漸變窄,而在w1=0.7996的乙醇溶液中受溫度影響變化小,且介穩區寬度較純水中窄。因此,在SDA結晶中,可採用w1=0.7996的乙醇溶液結晶分離SDA,且過飽和濃度需控製在介穩區內。
위제고쌍을산납( SDA)적산품질량,고찰료온도、용제조성、을산납함량등조건대SDA용해성적영향,채용동태법측정료SDA재불동질량분수을순-수、을산납-수혼합용제중적용해도,병측정료SDA재순수화질량분수위0.7996(w1=0.7996)적을순용액중적개은구。결과표명,SDA역용우수,미용우을순,수을순질량분수증가,SDA용해도강저유가현저,차재w1=0.7996적을순용액중강저최위명현;수산물중을산납함량증가,SDA용해도축점감소,차재질량분수위0.0832을산납용액중강저폭도최대;재300~315 K범위내,w1=0.7996적을순용액대SDA화을산납유명현적분리효과;SDA적개은구관도재순수중수온도승고축점변착,이재w1=0.7996적을순용액중수온도영향변화소,차개은구관도교순수중착。인차,재SDA결정중,가채용w1=0.7996적을순용액결정분리SDA,차과포화농도수공제재개은구내。
In order to imProve the quality of SDA,the effect of temPerature,solvent comPosition and NaAc content on the solubility of SDA in water were exPlored,the solubilities of SDA in ethanol and NaAc solu-tions were determined by dynamic method. In addition,the metastable zone of SDA in water and ethanol solution(w1 =0. 799 6)were obtained. The results showed that SDA was soluble in water,while slightly soluble in ethanol,and with the increase of ethanol in solvent mixtures,the solubilities decreased obvious-ly,esPecially the mass fraction of ethanol was 0. 799 6. Also,the solubilities of SDA decreased with the in-crease of NaAc in solvent mixtures,esPecially the mass fraction of NaAc was 0. 083 2. What’s more,etha-nol solution(w1 =0. 799 6)had Played an active role for the seParation of SDA and sodium acetate in the range of 300~315 K. The metastable zone of SDA in water gradually narrowed with the increase of tem-Perature,while in ethanol solution(w1 =0. 799 6)was little influenced by temPerature changes and was narrower. Therefore,ethanol solution(w1 =0. 799 6)can be used as mixed solvent for crystallization and seParation of SDA,and the suPersaturated concentration should be controlled in the metastable zone.