| The high pressure hydrogenation of naphthalene in mineral oil and cyclohexane solvents was studied in tubing bomb microreactors, trickle flow and vapor-phase continuous reactors, respectively, with unsupported iron catalysts, including the original iron oxide, hydrogen pre-reduced and in-situ sulfided forms. The order of decreasing hydrogenation activity was Fe {dollar}> >{dollar} FeS{dollar}rmsb{lcub}x{rcub}{dollar} or Fe{dollar}rmsb2Osb3{dollar}. The secondary hydrogenation reaction to form decalins from tetralin occurred only with the hydrogen reduced iron. Trickle bed experiments showed the iron oxide catalyst to be much more rapidly deactivated than the baseline NiMo/Al{dollar}rmsb2Osb3{dollar}. In vapor-phase operation using reduced iron as catalyst, rapid deactivation occurred with a 2.0 wt% naphthalene feed, whereas little deactivation was found with a 0.2% feed. Transport limitations found with NiMo/Al{dollar}rmsb2Osb3{dollar} catalyst extrudates were consistent with estimated effectiveness factors, and were eliminated by crushing the extrudates to 40-50 mesh. A proposed Langmuir-Hinshelwood rate expression was found to satisfactorily fit the data.; The surface area maintenance of the nanoscale Mach-I iron catalyst was studied with several different pretreatments. The introduction of sulfate ion to the catalyst surface by impregnation prevented the iron particles from agglomeration to certain degree. There appears an optimal surface area maintenance at 0.3-0.6 M ammonium sulfate promotion.; Direct coal liquefaction was conducted using Blind Canyon DECS-17 coal with Mach-I iron oxyhydroxide catalyst, its hydrogen reduced forms, and SO{dollar}sb4sp{lcub}2-{rcub}{dollar}, Mo, W, and Pt doped forms. All of the catalysts increased both pentane solubles (PS) and tetrahydrofuran solubles (THFS). However, catalysts impregnated with a second metal (or ion) showed approximately the same activity for PS and THFS.; A coal derived middle distillate was hydrotreated using three alumina supported commercial hydrotreating catalysts, NiMo, CoMo, and NiW, and their Pt promoted forms. The catalysts showed essentially the same activity in molecular type liquid product distribution, but the activity for product specific gravity reduction was approximately in the order of PtCoMo {dollar}>{dollar} PtNiMo {dollar}approx{dollar} NiMo {dollar}approx{dollar} CoMo {dollar}>{dollar} NiW. Catalyst deactivation for nitrogen removal was observed with NiMo and NiW catalysts. Promotion with Pt improved the HDN activity significantly. For the hydrocracking of hydrotreated coal liquid, the gas oil cut ({dollar}+205 spcircrm C{dollar}) conversion to naphtha cut ({dollar}rm -205spcirc C{dollar}) can be described using first order kinetics at conditions used in this study. The reaction rate was approximately inversely proportional to the feed nitrogen content. |
