FCC油浆中饱和烃的抽提方法研究

STUDY ON THE EXTRACTION SEPARATION OF SATURATED HYDROCARBONS FROM FCC SLURRY

以糠醛为抽提溶剂、正辛烷为第二溶剂,采用双溶剂抽提法对中国石化九江分公司和广州分公司FCC油浆进行抽提分离,得到饱和烃和芳烃,考察双溶剂抽提的操作条件及抽余油(富含饱和烃)的组成和裂化性能。结果表明,最佳的抽提条件为:温度50～70℃;第一阶段剂油比m(糠醛)∶m(油浆)∶m(正辛烷)=2.0∶1.0∶1.5,第二阶段剂油比m(糠醛)∶m(抽余相)=0.67∶1.00,第三阶段剂油比m(糠醛)∶m(抽余相)=1.20∶1.00;抽提次数8次,第四次和第五次抽提之间进行一次抽余相溶剂提浓。在该条件下,九江分公司和广州分公司FCC油浆抽提分离得到的抽余油中饱和烃质量分数分别为77%和74%,饱和烃收率分别为95.23%和91.58%,分离效果良好,且得到的抽余油具有良好的裂化性能,是优质的催化裂化原料。

Dual-solvent extraction of FCC slurry oil was performed with furfural as main solvent,n-octane as second solvent,the operation conditions,components of raffinate and its cracking performance were investigated.The optimal operation conditions were obtained as follows： extraction temperature in the range of 50—70 ℃;using 1st stage material mass ratios of m（furfural）∶ m（slurry）∶m（n-octane）=2.0∶1.0∶1.5,2nd stage of m（furfural）∶m（raffinate phase）=0.67∶1.00,3rd stage of m（furfural）∶m（raffinate phase）=1.20∶1.00;the entire process involved 8 extraction steps（1st step as 1st stage,2nd—4th steps as 2nd stage,5th—8th steps as 3rd stage） with an additional solvent enrichment step added between the 4th and 5th step.Under such optimal extraction conditions,using FCC slurry oils from SINOPEC Jiujiang Petrochemical Company and SINOPEC Guangzhou Petrochemical Company as feed respectively,the mass fractions of saturated hydrocarbons in raffinates were 77% and 74%,respectively;the yields of saturated hydrocarbons reached 95.23% and 91.58%,respectively.The separation of saturated hydrocarbons from aromatics was successful,and the raffinate exhibited excellent cracking performance,it could be used as a high quality FCC feedstock.