高校化学工程学报
高校化學工程學報
고교화학공정학보
JOURNAL OF CHEMICAL ENGINEERING OF CHINESE UNIVERSITIES
2013年
6期
980-984
,共5页
于秋硕%马晓迅%徐龙
于鞦碩%馬曉迅%徐龍
우추석%마효신%서룡
丁二酸%结晶动力学%表面活性剂%模型
丁二痠%結晶動力學%錶麵活性劑%模型
정이산%결정동역학%표면활성제%모형
succinic acid%crystallization kinetics%surfactants%model
杂质可以影响结晶过程中晶体的成核与生长,其影响一般由杂质在晶面上的吸附而导致的溶质固液界面能改变引起。本文基于表面活性剂双亲结构所具有的界面效应,以丁二酸冷却结晶体系作为研究对象,考察了表面活性剂对晶体生长过程的影响。发现表面活性剂可以明显地抑制晶体的生长速率;运用Malkin提出的描述过饱和度和晶体生长速率关系的理论模型对表面活性剂的影响过程进行分析,发现在表面活性剂存在下晶体表面被吸附的溶质分子的密度要明显小于纯水体系。
雜質可以影響結晶過程中晶體的成覈與生長,其影響一般由雜質在晶麵上的吸附而導緻的溶質固液界麵能改變引起。本文基于錶麵活性劑雙親結構所具有的界麵效應,以丁二痠冷卻結晶體繫作為研究對象,攷察瞭錶麵活性劑對晶體生長過程的影響。髮現錶麵活性劑可以明顯地抑製晶體的生長速率;運用Malkin提齣的描述過飽和度和晶體生長速率關繫的理論模型對錶麵活性劑的影響過程進行分析,髮現在錶麵活性劑存在下晶體錶麵被吸附的溶質分子的密度要明顯小于純水體繫。
잡질가이영향결정과정중정체적성핵여생장,기영향일반유잡질재정면상적흡부이도치적용질고액계면능개변인기。본문기우표면활성제쌍친결구소구유적계면효응,이정이산냉각결정체계작위연구대상,고찰료표면활성제대정체생장과정적영향。발현표면활성제가이명현지억제정체적생장속솔;운용Malkin제출적묘술과포화도화정체생장속솔관계적이론모형대표면활성제적영향과정진행분석,발현재표면활성제존재하정체표면피흡부적용질분자적밀도요명현소우순수체계。
Impurity can influence the crystal nucleation and growth progress. The influence usually attributed to the adsorption of impurity on face of crystal, which is the key factor to change solid-liquid interface energy. In this work succinic acid was selected as model system and the surfactants was used as the impurity due to its interfacial effect which is caused by its amphiphilic structure. The cooling crystallizations were conducted in the presence of three surfactants separately, and the crystal growth rates were measured respectively in the presence of different surfactants. Results show that the presence of surfactants inhibits the crystal growth obviously. The mechanism underlying the effect of three surfactants on crystal growth was further studied with the theoretical model proposed by Malkin which describes the relation between the face growth rate and the degree of supersaturation in the surface integration step. It shows that the three surfactants decrease the density of adsorbed molecules of the crystallizing solute on the surface of the crystal.