有机酸结构对α半水脱硫石膏晶体形貌的影响及其调晶机理  

Influnce of Organic Acid Structure on Crystal Morphology of α-hemihydrate Desulfurization Gypsum and Its Crystal Modification Mechanism

作　　者：彭家惠[1] 陈明凤[1] 张建新[1] 瞿金东[2] 邹辰阳[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400045 [2]重庆大学城市建设与环境工程学院,重庆400045

出　　处：《四川大学学报（工程科学版）》2012年第1期166-172,共7页Journal of Sichuan University (Engineering Science Edition)

基　　金：国家自然科学基金资助项目(50872160)

摘　　要：研究了有机酸羧基数量、羧基间距、羟基等辅助基团、双键及其顺反构造对α半水脱硫石膏晶体形貌的影响,从吸附和晶体生长角度分析了有机酸调晶机理。结果表明,一元有机酸没有调晶效果;羧基间距3个C原子的二元或多元有机酸是高效调晶剂,如丁二酸、柠檬酸等;邻位羟基有助调作用,使有机酸调节效果更好;顺式结构有机酸调晶作用略有增强,反式结构破坏羧基的协同作用,调晶能力基本丧失。有机酸2个羧基同时与Ca2+络合,选择吸附在α半水脱硫石膏(111)面,形成环状络合物,阻碍Ca2+扩散和晶面生长,削弱(111)面c轴生长速率的比较优势,改变α半水石膏晶体生长习性和形貌。The influence of carboxyl number,carboxyl distance,and other auxiliary groups such as hydroxyl,double bond and its cis/trans-structure of organic acid on the crystal morphology of α-hemihydrate desulfurization gypsum were studied.The crystal modification mechanism of organic acids was analyzed from the point of adsorption and crystal growth.The results showed that monoacid has no crystal modifying effect,while dibasic acid or polybasic acid with carboxyl distance of three C atoms such as succinic acid and citric acid are highly efficient crystal modifying agents.Adjacent hydroxyl groups have aid-modifying function to organic acids.Cis-structure could slightly enhance the crystal modifying effects of organic acids,while the trans-structure damages synergy reaction among carboxyl groups,leading to the ability lose of its crystal modification.Two carboxylic of organic acid complexs with Ca2＋,selectively adsorbed on the（111） face of α-hemihydrate desulfurization gypsum,formating ring-shaped complex compound,which hinder Ca2＋ diffusion and crystal growth,weakens the rative advantage of growth rate on（111） face in c-axis directions,and thereby changes the crystal growth habit and morphology of α-hemihydrate desulfurization gypsum.

关 键 词：Α半水石膏 有机酸 晶体形貌 调晶机理 

分 类 号：TQ177.3[化学工程—硅酸盐工业]