Petrochemical Petrochemical ProcessesProcesses

22.4.2. DESCRIBE THE BASIC BUILDING BLOCK PROCESSES IN PETROCHEMICAL TECHNOLOGY

EHTISHAM UL HAQ

Petrochemical Feedstocks The refinery products are: naphtha; gas oil and

catalytic cracker gases. NOTE: In oil industry: gasoline fraction In petrochemical industry, naphtha is the

petroleum fraction that boils between 20-80oC. Naphtahas: mix of alkanes, cycloalaknes and

aromatic hydrocarbons. Gas oils are mix of have the same components

but with higher molecular weights. Gas oils are used in place of naphtha as a

feedstocks for ethylene manufacture.

The Basic building Block Processes

In USA, large scale cracking : cracker gases are the precursors fro production of propylene and butenes.

In Europe and Japan, small scale cracking: cracker gases are sources fro ethylene.

Kerosine: chemical feedstock, manufacture of ethylene

• Petrochemical manufacturing involves building blocks processes for the manufacture of building blocks and intermediates.

• Petrochemical industry is based on intermediates.• Known Petrochemical Processes: Thermal cracking; catalytic cracking and steam reforming.

The Basic building Block Processes (Cont.)

Cracking: Steam cracking, Catalytic cracking for olefins pyrolysis gasoline by product

Steam reforming and Partial oxidation: Synthesis gas

Catalytic Reforming: Aromatic production Aromatic conversion processes: Aromatic

production Alkylation: Linear alkyl benzene OXO Process: Oxo-alcohol Polymerisation Process: Polymer,

elastomers and synthetic fibre

Thermal Cracking Also known as steam cracking, is used for manufacture of

ethylene. Feedstocks: ethane, propane, naphtha and gas oils. When ethane is cracked ethylene Propane propene + co-product Naphtha and gas oil propylene, butene, butadiene and

aromatic compounds.Catalytic reforming

• Used for making BTX.• Feeedstck: naphtha

Steam reforming• Used for producing a mix of CO and H2.• Intermediate for making NH3, CH3OH

Petrochemical Process Technology

Petrochemical processes are normally Continuous Processes; the raw materials are continuously fed into the plant so as the products.

Petrochemical plant would have one or more reaction systems.

C6H6 + C2H4 C6H5C2H5 C6H5CH=CH2 + H2

Polymerization is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks.

There are many forms of polymerization and different sys Usually at least 100 monomer molecules must be combined to

make a product that has certain unique physical properties—such as elasticity, high tensile strength, or the ability to form fibres—that differentiate polymers from substances composed of smaller and simpler molecules; often, many thousands of monomer units are incorporated in a single molecule of a polymer.tems exist to categorize them.

he formation of stable covalent chemical bonds between the monomers sets polymerization apart from other processes, such as crystallization, in which large numbers of molecules aggregate under the influence of weak intermolecular forces.

Polymerization