Abstract
In the preceding paper12), a new modified method was proposed to analyze such structural factors as the number of naphthene rings and ring compactness of petroleum heavy ends and coal tar pitches by using model compounds. But, the method12) was not applicable to the structural analysis of insoluble materials such as coal in organic solvent. An attempt has been made to develop an analytical method applicable to insoluble materials.
In this paper, a new approach is proposed by which the structural analysis of such materials mentioned above, could be performed. This method utilizes elementary analysis (C, H, N, S), IR, density and molar refraction together with a modified Montgomery's molar refraction equation10).
For developing a calculation system, the following assumption were made for the analytical calculation of average chemical structure based on the experience gained over a long period of time in the structure analysis of coal extract and pitches.
1) Absence of quaternary carbon atoms.
2) Absence of double bonds without the aromatic rings.
3) Each condensed ring system is bonded by a paraffinic chain, and the paraffinic chain number is the number of condensed ring systems in a molecule minus 1.0.
4) The structure may contain no naphthene rings. When naphthene rings are present, one or more naphthene rings must be contained in each ring system of the molecule.
Also, three "floating paramctcrs", Φ, FB, and FC, are used.
The valid ranges of these parameters are;
0_??_Φ_??_1
0_??_FB_??_1
0<FC_??_1
The calculated structural factors of pitchlike materials by using this method agreed with those from the previous method12) (Tables 4, 5).
Thus, the structural analysis of solid-carbonaceous materials such as coal became possible based on the analytical data. Unit structures are obtained from calculations by this method, because molecular weights of solid-carbonaceous materials are not measured.
The chemical structural transformation studies of aromatic heavy oil ends in carbonization become possible using this analytical method. Besides, characterizations of solid-carbonaceous materials such as coal will become attainable using the structural factors obtained by this analytical method.
