Page 249 - Principles of Catalyst Development

GLOSSARY OF COMMON TERMS 239
Dehydrogenation The reverse of hydrogenation, involving the splitting off of
hydrogen to give a less saturated compound and the rupture of a C-H bond.
Demetallization Removal of metal (iron, nickel, and vanadium) porphorins by
a combination of hydro treating and adsorption.
Desulfurization Same as hydrodesulfurization.
Dinuclear Aromatics Fusion of two benzene rings with two common carbon
atoms.
Dismutation The same as disproportionation.
Disproportionation Splitting of a hydrocarbon into two different hydrocarbons,
with one a lower and the other a higher carbon number and no gain or loss of
hydrogen.
Distillation A mechanical process for the separation, under atmospheric pressure
or vacuum, of crude oil into various boiling point fractions.
Doctor Test A test for mercaptain sulfur in petroleum products.
DualOxygenolysis Rupture ofC-C and C-H bonds to give both H 20 and CO 2 •

Fischer- Tropsch Reactions Reaction of CO and H2 to produce paraffins, olefins,
alcohols, aldehydes, ketones, and fatty acids.
Fixed Carbon The organic portion of residual coke obtained on evaporation to
dryness of hydrocarbon products in the absence of air.
Free Carbon Organic matter in tars that is insoluable in carbon disulfide.
Formulation Production of an aldehyde or ketone from a hydrocarbon and
carbon monoxide without using hydrogen.
Gas Hourly Space Velocity (GHSV) Volume of gas (STP) per volume of catalyst
per hour.
Gas Oil Petroleum fractions boiling in the ranges 200-350°C (light), 325-400°C
(medium), and 380-575°C (vacuum).
Halogenation Addition of a halogen atom (F, CI, 8r, and I) to a molecule.
Heat Transfer Limited Reaction An endothermic reaction whose rate is deter-
mined by the rate of heat transfer to the reactor.
Hydration Addition of H 20 or a compound containing active hydrogen, such
as NH 3 •
Hydrocarboxylation Formation of an acid from an alkene, CO, and H2 0.
Hydrocracking A dual-type reaction of cracking and hydrogenation to produce
saturates of high octane value from heavier compounds. It is accompanied by
the hydrogenolysis of C-S, C-N, and C -0.
Hydrodealkylation Removal of an alkyl side chain from an alkyl aromatic by
substituting hydrogen.
Hydrodenitrogenation Removal of nitrogen as NH3 by the addition of hydrogen.
Hydrodesulfurization Removal of sulfur as H2 S by the addition of hydrogen.