Petrochemicals: Finishing and Products

A set of vocabulary flashcards covering the processes of catalytic reforming and alkylation, octane rating references, and key aromatic precursors.

Catalytic Reforming

A process that improves the octane number by rearranging the structure of hydrocarbon molecules, typically using a feed of straight run naphtha containing paraffins and naphthenes.

BTX

An abbreviation for Benzene, Toluene, and Xylene, which are aromatics produced through catalytic reforming used as industrial solvents and chemical precursors.

Alkylation

The process of combining light olefins with isobutane to produce larger iso-paraffins, known as alkylates, in the gasoline range of $C_5-C_{10}$.

Octane Number

A fuel specification that measures the likelihood of petrol to pre-ignite in an engine; high values indicate better resistance to knocking.

Knocking

A condition where gasoline vapor self-ignites before the piston reaches the top of its stroke, leading to power loss, jerky rides, and permanent engine damage.

n-heptane

A hydrocarbon assigned an octane number reference point of $0$ due to its high tendency to cause knocking in engines.

2,2,4-trimethylpentane (iso-octane)

A branched hydrocarbon assigned an octane number reference point of $100$, representing a smooth-running engine.

Platforming

A specific type of catalytic reforming that utilizes a platinum catalyst to permit careful control of the product types.

Isomerization

A reaction in catalytic reforming that increases the octane number by converting straight-chain paraffins into branched iso-paraffins.

Aromatization

A catalytic reforming reaction, favored by high temperature and low pressure, that converts cycloparaffins or olefins into aromatic compounds.

Tetraethyl lead (TEL)

A gasoline additive used to increase the octane number, though its usage has declined due to health and environmental issues.

MTBE (methyl tertiary butyl ether)

A potentially carcinogenic gasoline additive used as an octane booster.

Benzene

A clear, colourless, sweet-smelling, and flammable liquid produced by catalytic reforming; it is a precursor for drugs, plastics, detergents, and dyes.

Toluene

An aromatic product used as a solvent, in printing ink, and in the production of explosives.

Xylene

An aromatic hydrocarbon used as a solvent in the printing, rubber, and leather industries.

Naphthenes

Also known as cycloalkanes, these are a major component of the feed for catalytic reforming alongside paraffins.

HF (hydrofluoric acid)

A catalyst used in alkylation to reduce operating temperatures and minimize unwanted side reactions.

Alkylates

The products of alkylation characterized as excellent motor fuels due to their stability, high octane number, and low vapour pressure.

Hydrocracking

A non-desired side reaction in alkylation where hydrogen is consumed and larger molecules are broken down into lighter gases if the temperature is too high.

MMT

Methyl cyclopentadienyl manganese tricarbonyl, an octane booster used in gasoline that may contain high-RON aromatics.