摘要
为了确定尿素和氯化铵两种肥料形成加合物的条件和性质,采用等温法分别对25℃和35℃下NH4Cl-CO(NH2)2-H2O三元体系相平衡进行了研究,测定了溶解度数据,并绘制了完整的相图。得出实验条件下,氯化铵与尿素能形成摩尔比为1:1的加合物;该体系相图存在NH4Cl、CO(NH2)2、CO(NH2)2.NH4Cl三个纯固相结晶区,和NH4Cl与CO(NH2)2.NH4Cl及CO(NH2)2与CO(NH2)2.NH4Cl两个共结晶区。对氯化铵与尿素的加合物及其两者组成混合物进行红外、热稳定性、X衍射等分析表征可知,NH4Cl与CO(NH2)2形成的加合物没有产生新的共价健,但加合物的红外特征峰相对于纯物质发生小量的位移,加合物热稳定性比混合物稍低。
In order to determine the formation conditions and property of the adduct of NH4Cl and CO（NH2）2, the phase equilibriums of the NH4Cl-CO（NH2）2-H2O ternary system at 25℃and 35℃ were studied. The solubilities of NH4Cl-CO（NH2）2-H2O system at 25℃2 and 35℃ were determined, and the phase diagrams of the system were plotted. It was found that the adduct of NH4Cl and CO（NH2）2 can be formed in this system, and there are NH4Cl, CO（NH2）2 and CO（NH2）2＇NH4Cl three pure solid phase crystal regions, NH4Cl with CO（NH2）2＇NH4Cl and CO（NH2）2 with CO（NH2）2＇NH4Cl two solid mixture phase crystal regions in these phase diagrams. The CO（NH2）2＇NH4Cl adduct and mixture of NH4Cl and CO（NH2）2 were characterized by X-ray diffraction （XRD）, Fourier transform infrared spectroscopy （FT-IR） and thermogravimetric analysis （TGA）, respectively. The results show that the adduct has no new covalent bond formed between NH4Cl and CO（NH2）2, but the infrared peak positions of adduct shift a little comparing with those of pure substances NH4Cl and CO（NH2）2, and the thermal stability of adduct is a little smaller than that of the mixture of NH4Cl and CO（NH2）2.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2007年第5期864-868,共5页
Journal of Chemical Engineering of Chinese Universities
关键词
尿素
氯化铵
相平衡
溶解度
相图
加合物
urea
ammonium cholride
phase equilibrium
solubilities： phase diagram
adduct
