超临界流体色谱法分离柴油中的芳烃

石油燃料如汽油、天然气等中含有如脂肪烃、芳烃、烯烃等许多成分。分析这些成分是非常重要的，因为这些成分极大地影响了燃料的效率和发动机燃烧后排放的环境污染物的量。高效液相色谱（HPLC）、气相色谱（GC）或超临界流体色谱（SFC）被广泛应用于石油燃料的分析。在这些方法中，超临界流体色谱被用于得出ASTM（美国测试和材料学会）方法，因为石油燃料中的成分可以高分辨率分离，可以在短时间内进行高稳定性分析。本文根据ASTM D5186所报道的超临界流体色谱系统对柴油中的多环芳烃成分进行了分析。Application Note 2/3Application NoteSeparation of Aromatics in Diesel Fuel Separation of Aromatics in Diesel Fuel by Supercritical Fluid Chromatography [ASTM D5186] Many components i ncludi n g aliphat i c hydrocarbons an d aromatic hydrocarbons such as paraff i ns and olefins are contained i n petroleum fuel such as gasoline ， gas oil， etc. Analyz i ng these components is very important because these components greatly affect the ef f iciency of the fuel and the amount of environmental pollutant which is discharged from engine after burning.Separation analysis methods such as High Performance Liquid Chromatography (HPLC)，Gas Chromatography (GC) or Supercritical Fluid Chromatography (SFC) are w i dely used for analyzi n g petroleum fuel. Among those methods， Supercritical F l uid Chromatography has been used to der i ve an ASTM (T he American Society for Test i ng and Material) method because the components in pet r oleum f uel ca n be separated with high resolution and can be analyzed in a short ti me with high stability. This t ime po l ycyclic aromatic components i n diesel fuel were analyzed using Supercritical Fluid Chromatography system in accorda n ce with ASTM D5186 as reported be l ow. Keyword： SFC， 5 um， Diesel fuel ， ASTM 5186，Hexadecane， Toluene， Tetralin， Naphthalene Experimental Equipment： Conditions： CO2 Delivery PU-2080-CO2 Pump Reagent pump： X-LC 3159AS (4.6 mml.D. x 250 mmL， 5 um) (0.5 uL injection model)*1 Column Oven： CO-2060 Detector： FID (GC-390B) Back Pressure BP-2080 Regulator： Column： FCpak SIL-PA (4.6 mml.D. x250 mmL， 5 um) Eluent： Carbon dioxide Flow rate： 2.0 mL/min Column 35°C Temperature： Back Pressure： 20 MPa Injection Volume： 0.5uL Standard Sample： Hexadecane=75 mass%， Toluene=20 mass%， Tetraline=3 mass%，Naphthalene=2 mass% Oven： 200°℃， FID； 350°℃ Re sul t s O v er l a p p ed ch rom at ogr a ms (n = 10) of s t a n da rd m i x tu re is s h o w n i n f i gur e 1， an d t h e r e su l t of r et e nt io n ti m e r epeatab i l ity is s h own a s i n T a ble 1. Th e r epe a tabi l i t y o b tain e d w a s less tha n 0.2% a nd t h e r e s o l u t io n of H e x ad e c a n e a n d T ol u e n e was 11.2， and th e r esol u ti o n o f T e t r al in a n d Na p h t h a l e ne， 4.9. Figure 1 Chromatogram of t he S t and a rd M i xt u re 1.Hexad e cane， 2.To l uene， 3.T et r a l in，4.N ap htha l e n e T a b l e 1 Ret e n t i o n Ti m e R ep e a t abili t y o f St an d a r d Mi x tu r e (n=10) Hexadecane Toluene Tetraline Naphthalene 1 1.362 2.293 2.908 3.602 2 1.363 2.295 2.910 3.603 3 1.363 2.295 2.912 3.602 4 1.363 2.295 2.912 3.607 5 1.367 2.298 2.915 3.608 6 1.363 2.293 2.908 3.602 7 1.360 2.290 2.905 3.597 8 1.363 2.293 2.908 3.598 9 1.360 2.290 2.903 3.597 10 1.358 2.287 2.902 3.590 Sum 13.623 22.930 29.083 36.005 Average 1.362 2.293 2.908 3.601 S.D. 0.0024 0.0033 0.0041 0.0053 CV% 0.175 0.145 0.141 0.148 Th e c h r o m a t ogra m o f com me r ci a l l y av a ilabl e g as oi l i s s hown as i n f i gur e 2. T h e ar e a pe r c en t o f e ac h c omp o n en t w a s ： n on -a r oma t i c s ： 71.8%， a nd ar omat ic s ： 28.2%. F igure 2 C h r o ma t ogram o f G as O i l A p plicat i o n L i br a r y ： htt p ：//www.j as co i n c .c o m /ap p l i c a ti o n s