CATALYTIC HYDROPROCESSING OF THE NEUTRAL-OILS, BASIC, AND NEUTRAL-RESINS FRACTIONS OBTAINED FROM HYDROLIQUEFIED COAL

Hydroprocessing of coal liquid fractions (neutral oils, strong and very weak bases, and neutral resins), separated by preparative liquid chromatography from SRC-II heavy distillate, was carried out at 325-400(DEGREES)C and 120-142 atm with sulfided Ni-Mo/(gamma)-Al(,2)O(,3) catalyst in isothermal plug-flow microreactors and a batch reactor. The relative simplicity of the fractions, each consisting of chemically similar compounds, allowed quantitative determination of reactivities of representative groups in the fractions as well as of individual compounds. The reactivities determined from group-type analyses (high- and low-resolution mass spectrometry, proton NMR, etc.) are in good agreement with reactivities of individual compounds determined by gas chromatography/mass spectrometry.;In batch hydroprocessing of the neutral oils at 355(DEGREES)C and 36 atm, the rate constants for hydrodesulfurization, hydrogenation, and hydrodeoxygenation were of the order of 10('-6), 10('-7), and 10('-7), L/(g of catalyst(.)s), respectively. There was little evidence of cracking during the 25-hr reaction time. The neutral oils fraction appears to be a promising feedstock.;The major constituents of the strongly basic fraction were determined by GC and GC/MS to be benzoquinolines, naphth(2,1,8-def)-isoquinoline, biphenylamine, and their methyl substituted derivatives. The total nitrogen removal data obtained at 400(DEGREES)C indicated the following order for the hydrodenitrogenation reactivities: neutral resins > very weak bases >> strong bases. Increasing temperature or hydrogen concentration increased the rate of hydrodenitrogenation of these fractions. GC and GC/MS of the products indicated that hydroprocessing had markedly increased the compositional complexity. The products indicated the occurrence of hydrogenation and hydrogenolysis.;The pseudo-first-order rate constants for removal of dibenzothiophene, 4-methyldibenzothiophene, and methyldibenzothiophene (an unknown isomer) in the neutral oils were determined to be 5.8 x 10('-5), 1.8 x 10('-5), and 10.7 x 10('-5) L/(g of catalyst(.)s), respectively, at 355(DEGREES)C and 120 atm. The rate constant for dibenzothiophene is in agreement with the value obtained by extrapolation of published data for dibenzothiophene in n-hexadecane. There was negligible inhibition of hydrodesulfurization reactions by aromatic hydrocarbons in the neutral oils.