**1. Introduction**

In the processing of coal and petroleum, there are many products produced such as gas and lighter liquid which is easy to use. At the same time, there is heavy material produced which is difficult to use. Such as, in crude oil refine processing, oil thermal cracking and catalytic cracking of petroleum, many residua oils, asphalts, and heaviest "waste" residual will be produced. The quantity of heavy oils is often large. So, it is important to study the property of heavy oils.

The column liquid chromatography (CLC) is an important and indispensable analysis method to study heavy oils. It is not only a separation means, but is also analysis means, especially for analysis of hydrocarbon group type.

Hydrocarbon group type analysis means the determination of the following classes of compounds:


Now analysis methods existed have some deficiencies. Such as GC method can not be used to analyze compounds having high boiling point. The application of high performance liquid chromatography (HPLC) to hydrocarbon group-type analysis is characteristic with its high efficiency, high speed, and high sensitivity. But HPLC is only suitable for analysis of substances soluble in *n*-pentane [1].

TLC-FID [2-3] method can be also used to analysis the THF-soluble party in asphalt-samples and show great advantages. But, the components were combusted during TLC-FID analysis

Column Liquid Chromatography 3

The amount of alumina was from 1.5 to 1.8 gram. Total sample used was about 0.1 gram. The solvent of heptanes, mixture of heptanes/ dichloromethane (1/2.5, V/V) and mixture of dichloromethane/ trichloromethane (1/3, V/V) were as elutes corresponding to saturated hydrocarbon, aromatic hydrocarbon and resin respectively. The amount of heptanes, heptanes/ dichloromethane, and dichloromethane/ trichloromethane was 20ml, 35ml and 30ml respectively. Each fraction collected was dried in vacuum under 60oC until the weight

Through above group analysis, the experimental deviation and recovery of CLC method are summarized in Table 1. From Table, it can be seen that the average of deviation and recover

Tetracosane 0.0547(g) 100 98.095 -1.905 98.095 1017 Tetracosane 0.0508 100 97.964 -2.036 97.964 1020 Tetracosane 0.0311 27.154 26.658 -0.496 98.173 1201 Tetracosane 0.0285 26.571 25.638 -0.933 96.489 1202 Average -1.343 97.680 Dibenz(ah)anthracen 0.042 100 98.095 -1.805 98.095 1030 Dibenz(ah)anthracen 0.0442 100 97.964 -2.036 97.964 1103 Dibenz(ah)anthracen 0.0259 22.629 20.909 -1.720 92.399 1201 Dibenz(ah)anthracen 0.0294 27.402 26.843 -0.559 97.960 1202 Average -1.530 96.605 Acetanilide 0.0875 100 97.600 -2.400 97.600 1024 Acetanilide 0.0247 23.024 22.642 -0.382 98.341 1202 Acetanilide 0.0365 100 96.438 -3.562 96.438 1222 Acetanilide 27.402 26.843 -0.559 97.853 1201 Average -1.726 97.558 Asphltene 0.0261 22.815 24.790 1.975 108.657 1201 Asphltene 0.0395 100 94.937 -5.063 94.937 1211 Asphltene 0.0387 100 98.450 -1.550 98.450 1301 Average -1.546 100.681

Determination W%

Deviation W%

Recover

% No.

Content W%

are -1.546% and 100.681% respectively; the results are good.

Weight of preparation

Table 1. Experimental deviation and recovery of model compound.

The result of CLC method was checked by Fourier transform infrared (FT-IR) method .The spectra IR were acquired in the transmission mode as 64 scan in the IR range from 4000 to 500cm-1 at a resolution of 4cm-1. KBr standard pellets were used, and the samples were dried

IR spectrums of pure reagents including tetracosane, dibenz(ah)anthracen and acetanilide were obtained and used for standards. The IR spectrums of different fractions collected from flow out separated of the mixture reagents, and spectrums were compared with above

**3.2 Check of chromatographic resolution rate by FT-IR** 

and then mixed with KBr, ground, and palletized.

standard spectrums. The results were shown in Figure 1.

keep constant.

Pure Reagents

process and this lack made it not suitable for other analysis with preparation fraction. It should be pointed that the conventional method such as ASTM method use amount of solvent is large and some solvents has high toxicity [4, 5]. Moreover, there are too troublesome for some operation in traditional method. Hence, the separation of products containing heavy components remains a difficult task up to now.

Refereeing the literatures [4-10], the authors of this paper establish an optimum CLC method to analyze group-type of heavy oils through a series of studies. This paper detail introduces this method and its many applications which include preparation of high-level road asphalt, the characterization of molecular weight distributions (MWDs) and analysis of heterocyclic aromatic components of heavy oils.
