CI - Rates, equilibria and the chemical industry Flashcards
In what 4 ways are there costs involved in producing a chemical?
1) Raw materials.
2) Fuel/energy.
3) Overheads/fixed costs.
4) Disposal costs.
How can raw materials be a cost involved in producing a chemical?
The plant needs to buy chemical for the reaction - cheap, widely available ones are best.
How can fuel/energy be a cost involved in producing a chemical?
Reactions needing high temperature or pressure will use up a lot of energy. Energy is also used in transporting chemicals to, from and around a plant, mixing them and purifying products.
How can overheads/fixed costs be a cost involved in producing a chemical?
No matter how much fuel or raw material a company uses, there are certain costs that need to be met regularly. These include staff wages, rent of equipment or space, taxes, insurance, telephone bills, etc.
How can disposal costs be a cost involved in producing a chemical?
Any unwanted by-products will have to be disposed of safely - this is subject to government regulations and can be very expensive.
What are by-products?
Unwanted waste products from a chemical process.
What are co-products?
Products which, whilst not as valuable as the main product, can still be useful and sold of for profit.
What type of reactions tend to be best for keeping costs low?
Reactions with high atom economies and high percentage yields as they use fewer raw materials and have fewer waste products. This saves money for a company.
What is there to consider when designing an industrial process?
The rate of reaction, product yield and cost.
What needs to be balanced against each other to come up with the right reaction conditions?
The rate of reaction, product yield and cost.
What do reaction conditions usually end up as a compromise between?
Several different factors.
What are chemical engineers trying to do when designing an industrial process?
Make as much product as they can, as cheaply and as quickly as possible.
Why when chemical engineers are designing an industrial process are they trying to make as much product as they can, as cheaply and as quickly as possible?
As this will make the company a bigger profit when they sell their product.
What are the advantages of using high temperatures for an industrial process?
Reactions go faster at higher temperatures, meaning more product will be made in the same amount of time.
What are the disadvantages of using high temperatures for an industrial process?
High temperatures make reactions more expensive to carry out because of the cost of fuel.
What are the advantages of using high pressures for an industrial process?
High pressures make gaseous reactions go faster.