F SC 432 Midterm Key – Flashcards
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| T/F? crude oil contains olefins |
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| False |
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| T/F? crude oil contains heteroatoms like S, N, and O |
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| True |
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| T/F? crude oil contains inorganic gases |
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| True |
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| T/F? crude oil contains metals such as Ni and V |
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| True |
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| T/F? crude oil contains naphthenes |
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| True |
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| name two organic gases that are typically found in crude oil |
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| CH4 (methane) C2H6 (ethane) |
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| T/F? Iso-alkanes have higher boiling points than n-alkanes with the same carbon number |
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| False |
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| T/F? Organic sulfur compounds tend to concentrate in the higher boiling fractions of crude oil |
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| True |
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| T/F? Boiling point of hydrocarbons decreases with the increasing carbon number |
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| False |
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| T/F? Vapor pressure (RVP) is not an important property of gasoline |
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| False |
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| T/F? Naphthenes have lower densities than n-alkanes with the same carbon number |
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| False |
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| Crude oil is generally classified as heavy or light according to ___ |
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| API gravity |
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| Characterization factors are calculated using ___ of crude oil |
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| physical properties |
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| What is the octane number n-heptane? |
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| 0 |
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| ASTM distillation temperatures of a light gas oil (at 95%vol) and a heavy gas oil (at 5%vol) obtained in an atmospheric distillation column are 580°F (i.e.,95% vol of LGO distilled) and 585°F(i.e., 5%vol HGO distilled), respectively. Mark the correct statement below. |
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| 95% LGO at 580 F & 5% HGO at 585 F 5 F ASTM gap (gap because HGO BP range is above the LGO range, which is expected) |
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| T/F? Disproportionation in visbreaking does NOT involve Formation of coke on the surface of visbreaker coils |
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| False |
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| T/F? Disproportionation in visbreaking does NOT involve Formation of light distillates from VDR |
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| False |
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| T/F? Disproportionation in visbreaking does NOT involve Production of fuel oil with a lower pour point than that of VDR |
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| False |
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| T/F? Disproportionation in visbreaking does NOT involve breaking of C-H bonds |
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| True |
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| The two principal strategies used in upgrading heavy fractions of crude oil are ___ and ___ |
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| carbon rejection hydrogen addition |
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| T/F? Fluid coking can process VDR with higher sulfur contents |
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| True |
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| T/F? Fluid coking produces only fuel coke |
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| True |
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| T/F? Delayed coking is used more frequently than fluid coking in the US refineries. |
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| True |
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| T/F? Fluid coking is a semi-continuous process |
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| False |
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| T/F? Flexi-coking process is a variation of fluid coking |
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| True |
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| Thermal cracking is carried out in two different reactors because... A. the conversion in a single reactor is not sufficient. B. one reactor could have a fixed-bed configuration. C. thermal reactivity of n-paraffins depends on the chain length. D. it is a continuous process. E. It is a semi-continuous process. |
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| thermal reactivity of n-paraffins depends on the chain length |
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| T/F? Radical combination is a propagation step in free radical chain reactions |
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| False |
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| T/F? Hydrogen abstraction from hydrocarbons is favored over beta-scission at lower pressures |
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| False |
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| T/F? High pressures during thermal cracking favors the formation of n-alkanes |
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| True |
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| T/F? Low pressures during thermal cracking favors the formation of n-alkanes |
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| False |
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| T/F? Initiation of free radical chain reactions involves heterolytic bond cleavage |
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| False |
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| Thermal cracking processes in US refineries have been replaced by catalytic cracking processes because... |
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| the isomerization of free radicals is very slow |
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| A similar concept for providing heat for cracking reactions was used in what two processes? |
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| fluid coking FCC |
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| Which two processes used a similar concept (using multiple reactors) to provide continuity of feedstock flow round the clock. |
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| delayed coking fixed-bed catalytic cracking |
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| on a TBP plot (TBP vs. vol % distilled), the line for the crude with the largest light and middle distillate yield would be... |
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| lowest in the low BP range |
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| on a TBP plot (TBP vs. vol % distilled), the line for the crude with the most aromatic light and middle distillate yield would be... |
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| highest in the low BP range |
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| on a crude oil ternary diagram, the cheapest crude would be |
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| closest to the top point (most aromatic) |
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| on a crude oil ternary diagram, the most expensive crude would be |
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| closest to the bottom left point (most paraffinic) |
