PREVENT WASTE

Rebecca Micallef

____________________________________________________________________________________________

"It is better to prevent waste than to treat or clean up waste after it has been created."

____________________________________________________________________________________________

Big image

EXPLANATION...

The first principle of Green Chemistry is PREVENTION. This prevention is at a molecular level and aims at minimising the amount of chemical waste produced in a reaction, as this is more efficient than cleaning up waste that has already been produced. The purpose of green is to produce the same amount of desired product as usual methods would, but with less of an effect to the environment, and prevention of waste is the first step in doing so.

THE PREVENTION PRINCIPLE

The E-factor is often referred to as a measure of waste or any other by-product produced by chemists BUT the desired product. More often than not this waste produced was seen as unavoidable, but Green Chemistry has allowed the production of the same amount of desired product with LESS waste!

PROCESS MASS INTENSITY

Process mass intensity - the ratio of total mass used in a process divided by the mass of the product.

Normally, the ratio of product to total mass used has been relatively small, causing the reactions used in many processes to result in a large amount of waste that may be detrimental to the environment.

However, when green chemistry is applied there is often a major decrease in the amount of waste produced with is obviously an important goal that has been achieved with the introduction of green chemistry to the industry.

____________________________________________________________________________________________

"For every 1kg of desirable product that is produced, an average of 25-100 kg of waste is produced."

_____________________________________________________________________________________________________

APPLICATIONS

Ibuprofen

An example of green chemistry that is used in the pharmaceutical industry is Ibuprofen, where in 1993 the processes of its production was reinvented using green chemistry.

The process begins with the exact same compound, however, the the process has been refined so instead of six steps involved, there are now only three. This new process produces slightly different drugs than previous methods, and these drugs can now be recycled.

Big image

THE BENEFITS

ECONOMIC

Green Chemistry has allowed chemists to reduce the costs in the processes of chemicals and drugs substantially. If less are involved in a process, then less money needs to be spent on its synthesis, and also, if less waste is produced then less money is spent on the clean up of this molecular waste.

ENVIRONMENTAL

Many harmful chemicals end up in the environment either intentionally (including pesticides), unintentionally such as emissions or by disposal of certain chemicals simply because there is nowhere else for them to go. Green chemistry allows different by-products to be produced and these are able to degrade or be used in other processes. This then results in less chemical disruption to the environment helping our eco-systems, plants and animals to suffer less from toxic harm.

HEALTH

If less toxic waste is being produced, then we will all have cleaner air to breathe, cleaner water, safer food and an all-round lessened exposure to toxic chemical waste. Workers in chemical factories will also thrive in the benefits of green chemistry and their work will become safer for their health.