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OXFORD AND CAMBRIDGE SCHOOLS EXAMINATION BOARD.
General Certificate Examination - Advanced Level
Chemistry (Salters') - Paper 3 mock.
ROBERT TAYLOR U6JW.
THE ROLE CATALYSTS IN CHEMICAL REACTIONS, THEIR IMPORTANCE IN INDUSTRY,
PROBLEMS AND NEW DEVELOPMENTS.
A Catalyst is a substance that alters the rate of a reaction.
The catalyst remains unchanged at the end of the reaction. The process
is called catalysis. In this report I aim going to explain the role of
catalysts in chemical reactions and their importance in industry.
I will also outline the problems associated with the use of some
catalysts and discuss, using appropriate examples, new developments in
this area which will help reduce damage to the environment.
The process of catalysis is essential to the modern day manufacturing
industry. Ninety per cent, over a trillion dollars' worth, of
manufactured items are produced with the help of catalysts every year.
Friedel–Crafts acylation overview
FC acylation step 1
FC acylation step IIIt is therefore logical that scientists are constantly searching for
new improved catalysts which will improve efficiency or produce a
greater yield.
An acidic catalyst works due its acid nature. Catalysts are strong
acids and readily give up hydrogen ions, or protons: H+. Protons can be
released from hydrated ions, for example H3O+, but more commonly
they are released from ionisable hydroxyl groups (R-OH) where the O-H
bond is broken to produce R-O- and H+. When the reactant receives
protons from an acid it undergoes a conformational change, (change in
shape and configuration), and becomes a reactive intermediate. The
intermediate can then either become an isomer by returning a proton to
the catalyst, or it may undergo a further reaction and form a
completely new molecule.
Up until the mid - 1960's silica-alumina gels were used to catalyse the
cracking of hydrocarbons. This...