The sources of petrochemicals (crude oil, a fossil fuel) will eventually run out and alternatives need to be found.
The petrochemical industry provides fuels such as petrol and diesel and the raw materials to make the polymers that are so much a part of our everyday living. The sources of petrochemicals, such as crude oil, a fossil fuel, will eventually run out and alternatives need to be found.
Before petrochemicals became readily available, people used a wide variety of materials that are renewable. Renewable materials can be replaced at the same rate as they are consumed. Wood was, and is, extensively used as a fuel and a construction material. In some countries animal dung was used as a fuel source. Cotton from plants, wool from animals, and silk from insects are all natural fibres that were in use well before synthetic fibres made from petrochemicals were introduced. It is possible that, as petrochemicals become scarcer and more expensive, these natural materials may be produced in greater quantities to meet demand.
Feedstock is a reactant used in an industrial process that is produced from the raw materials.
Biomass is carbon-based matter mainly derived from plants.
The current availability and relatively low cost of crude oil has hampered research into the development of alternative methods to manufacture fuels and feedstock for the production of plastics.
As ethylene is the major feedstock for the production of plastics, then the development of new ethylene sources is the first step in reducing the dependence on crude oil. One important candidate is biomass. Carbohydrates represent about 70% of biomass. Cellulose, hemicelluloses and sugars are important carbohydrates.
Large areas of fertile land and fertilisers are needed to grow crops to harvest the biomass. Biomass is currently being used on a small scale for the generation of electricity in the USA. Heat energy that is released from the combustion of biomass can be used to power steam turbines that generate electricity.
Cellulose is a polymeric material that can be broken down and fermented to produce ethanol. Ethanol can be used as a fuel. Ethylene can also be readily produced from ethanol.
Vegetable oils, such as canola, are being looked at as an alternative to diesel fuel, and ethanol, produced from the fermentation of sugar, is a possible substitute for petrol.
There are concerns that because the polymers produced from petrochemicals, with very few exceptions, are non-biodegradable they cause problems to the environment.
Biodegradable substances are broken down by the action of natural processes.
Natural polymers are more likely to be biodegradable.
Australia has vast reserves of coal. The energy released from the combustion of coal is used to generate electricity. Currently, coal is not used for the production of plastics or other petrochemicals. Research has shown that coal can be converted to liquid hydrocarbons but the process is expensive and has many problems. The removal of metallic minerals, oxygen and sulfur from the liquefied coal would require new, cost-effective techniques.
Post time: Jun-26-2017