week 3

Question 1

also known as ____, are saturated compounds that have the general
formula CnH2n+2

, where n is the number of carbon atoms.

Answer 1

Paraffins

Question 2

are* branched-type* hydrocarbons that exhibit structural
isomerization.

Answer 2

Isoparaffins (or isoalkanes)

Question 3

also known as ________, are unsaturated hydrocarbons containing
carbon–carbon double bonds.

Answer 3

olefins

Question 4

also known as ____________, are saturated hydrocarbons that have at
least one ring of carbon atoms.

Answer 4

Naphthenes,
cycloalkenes

Question 5

are unsaturated cyclic compounds composed of one or more benzene
rings.**

Answer 5

Aromatics

Question 6

is at the front-end of the refinery, also known as
topping unit, or atmospheric distillation unit.

Answer 6

Crude distillation unit (CDU)

Question 7

To extract more distillates from the atmospheric residue, the bottom from the
atmospheric CDU is sent to the _________________.

Answer 7

vacuum distillation unit.

Question 8

This is the only physical process where carbon is rejected from heavy petroleum
fraction such as vacuum residue.

Answer 8

SOLVENT DEASPHALTING (SDA)

Question 9

The sulfur content of crude oils varies from less than 0.05 to more than 10 wt% but
generally falls in the range of

Answer 9

1–4 wt%.

Question 10

The salts carried with the products act as ______________ in catalytic cracking
units.

Answer 10

catalyst poisons

Question 11

In this process, lube oil stock is treated by a solvent, such as N-methyl pyrrolidone
(NMP), which can dissolve the aromatic components in one phase (extract) and the
rest of the oil in another phase (raffinate).

Answer 11

SOLVENT EXTRACTION

Question 12

The raffinate is dissolved in a solvent (methyl ethyl ketone, MEK) and the solution
is gradually chilled, during which high molecular weight paraffin (wax) is
crystallized, and the remaining solution is filtered.

Answer 12

SOLVENT DEWAXING