摘要
本文采用溶剂结晶法工艺，用乙醇作溶剂，对本钢焦化厂工业萘的精制进行了较为系统的研究。测定了乙醇－萘体系的介稳区宽度及超溶解度曲线；考察了溶剂比，降温速度等因素对产品质量的影响；对产品萘中的主要杂质苯并噻吩的含量进行了考察；提出了溶剂循环二次结晶法的工艺流程。此外，还对该法的放大实验进行了初步探讨。实验结果表明，乙醇作溶剂一次结晶的萘产品结晶点为７９．５℃，对苯并噻吩的脱除率为５０％左右；二次结晶萘产品的结晶点达７９．８７℃，对苯并噻吩的脱除率达７３．２％，产品萘完全符合国家一级精萘的标准。放大实验表明，溶剂结晶法易于实现工业化。
Purification of Benxi distillate naphthalene are studied by crys- tallization from its EtOH solution in a batch stirring-tank crystallizer in this paper.The metastable zone width and supersolubility of naphthalene-ethanol system are determined.The effects of solvent/crude naphthalene(wt/wt)and cooling rate on the of products are investigated.The relationship between content of major impurity benzothiophene in product and solvent/crude naphthlene and cooling rate are discussed.Furthermore,a new technique called“Two Steps Solvent Circulating Crystallization”is put forward.The results show that the solidification point of one step crystallization product is about 79.5℃ and half of the benzothiophene in crude naphthalene is removed. The solidification point of two steps crystallization pro- ducts all exceed 79.6℃ and meet the first grade pure naphthalene of national stan- dards.
出处
《煤炭转化》
CAS
CSCD
北大核心
1995年第4期90-95,共6页
Coal Conversion
关键词
萘
乙醇
结晶
精制
焦油
naphthalene,Et al,crystallization,purification
