超临界异丁烷萃取分馏微晶蜡的研究

Supercritical Isobutane Fractionation of Microcrystalline Wax

微晶蜡在许多领域获得了广泛的应用,微晶蜡的许多高附加值的应用与其熔点及精制程度关联,微晶蜡的性能,尤其是熔点主要取决于原料减压渣油,传统的分离技术(如蒸馏)不适合于微晶蜡的进一步分离,研究微晶蜡的进一步切割分离技术,对于由低熔点微晶蜡原料制备附加值更高的高熔点微晶蜡具有重要意义。超临界流体分离技术具有的特性使之尤其适合低挥发性物系的分离切割,本研究对超临界异丁烷萃取分馏微晶蜡进行了研究,考察了各种工艺参数的影响。结果表明:分馏塔内形成一定的温度梯度和程序升压速度是最关键的影响参数。超临界异丁烷萃取分离技术可以按熔点高低的顺序将微晶蜡分成熔点不同的系列馏分,同时,分离出的馏分的色度有较大改观,表明超临界异丁烷萃取分离技术分离微晶蜡在分离的同时具有一定的脱杂质能力。

Microcrystalline wax has been widely used in many fields.Many high value-added applications of microcrystalline wax are related to its melting point and degree of refining.The performance of microcrystalline wax,especially the melting point,mainly depends on the raw material vacuum residue.The traditional separation technology(such as distillation)is not suitable for the further separation of microcrystalline wax.The further cutting and separation technology of microcrystalline wax is of great significance for preparing high-melting microcrystalline wax with higher added value from low melting point microcrystalline wax raw materials.The characteristics of supercritical fluid separation technology make it especially suitable for the separation and cutting of low-volume systems.In this study,extraction and fractionation of microcrystalline wax in supercritical isobutane was studied,and the influence of various process parameters was investigated.The results show that the formation of a certain temperature gradient and the program pressure increase rate in the fractionation column are the most critical influence parameters.The supercritical isobutane extraction and separation technology can separate the microcrystalline wax into a series of fractions with different melting points.At the same time,the chroma of the separated fractions is greatly improved,indicating that the supercritical isobutane extraction and separation technology has a certain ability to remove impurities.