Skip to main content

Industry and calculations

Watch this to unpack the calculations of industrial reactions in Higher Chemistry (and why the environment depends upon them)

search thinkfour.

We all should want our world to be more environmentally friendly and Chemistry has a big part to play in this. From making everyday items, such as paint to medicine, Chemistry can reduce impact, waste and resource consumption.

Type 2 Diabetes is a common health condition that causes the level of sugar to become too high in blood. The pharmaceutical industry is where research and development leads to full scale production of medicine. Originally, medication for Type 2 diabetes was created using a metal catalyst which can be damaging to the environment, but research is being done into creating medicine that uses an enzyme process which reduces waste, increases yield and is safer. Win-win, right?

More and more green chemistry is being adopted, creating processes that are financially viable, are better for the environment and are changing the face of industry.

Let’s look at the science…

this is thinkfour

Feedstocks are chemicals from which other chemicals are manufactured and are made from raw materials that are found from the earth. They are a substance that we might start with. It is necessary to think about how available they are, the cost of obtaining them, and what their impact on the environment is. Is it from a finite raw material? Is it a toxic substance?
Thinking about reactants, we need to calculate if we have one that is in excess. Having a cheaper reactant in excess is financially wise as this helps to ensure that the more expensive reactant is fully reacted and used up. However, you don’t want too much excess reactant as this can waste reactor space.

One way to minimise waste is to find opportunities to recycle any unused reactant or any by-product back into the system. For example, if water is produced in a reaction step, could it be reused elsewhere in the reaction? The ideal is to have minimal by-products that have to be dealt with. The percentage of by-product can be calculated using atom economy which is a measure of the proportion of reactant atoms that are in the desired product. So if a by-product cannot be recycled, depending on what the substance is, it could be sold onto another company if it is financially viable and if the by-products have to be disposed of this needs to be done safely.

Some industrial processes need to be heated for the desired reaction to proceed. The energy required needs to be balanced between the cost of supplying it, the temperature required for a profitable rate of reaction, and the enthalpy change of the reaction at equilibrium. It is also important to consider how the energy is obtained, is it based on fossil fuels or is it renewable?

Finally, let’s think about the product itself. It is important for an industrial process to have as a high a product yield as possible. At the research and development stage of forming a substance the method will be scrutinised so that the actual quantity of product formed, whether that’s mass or volume, is as close to the theoretical quantity as possible. Equilibrium conditions are designed to suit the forward reactions to help with this. With a multi-step process, there will be a number of opportunities for the yield to decrease. Having a high percentage yield is beneficial in terms of profit with less reactants required to get the desired quantity, and environmentally, with less unreacted substances to be dealt with. If it is appropriate, then having a product that biodegrades will also benefit the planet.

As I’m sure you will have noticed, there is a lot to consider when developing an industrial process. From the research stage to scaling to full on production requires problem solving, analysis, and creative minds in in chemistry but also in business too. We have seen green improvements in areas such as the process of decaffeinating coffee to types of catalysts being used in synthesising medicine to the development of computer chips.
Small steps are being made but hopefully in the future and perhaps with your help, Chemistry will find the balance between industrial production and protecting our world.

this was thinkfour, thanks for watching