Discuss the potential of cellulose as a raw material. (1 Viewer)

[nml10]

Question : Discuss the potential of cellulose as a raw material in the production of petrochemicals.

Answer : Cellulose is a good alternative raw material in the production of petrochemicals. Petroleum is a diminishing, costly fossil fuel whereas cellulose is an abundant biomass. The carbon chains in the beta-glucose molecules of cellulose could possibly be used to derive a source for ethylene.

This is a 3 mark question from an HSC Chemistry book. Could I get some feedback on my answer and some suggestions?

Thanks.

 

[UnrealAnchovies]

Question : Discuss the potential of cellulose as a raw material in the production of petrochemicals.

Answer : Cellulose is a good alternative raw material in the production of petrochemicals. Petroleum is a diminishing, costly fossil fuel whereas cellulose is an abundant biomass. The carbon chains in the beta-glucose molecules of cellulose could possibly be used to derive a source for ethylene.

This is a 3 mark question from an HSC Chemistry book. Could I get some feedback on my answer and some suggestions?

Thanks.

The key verb in the question is discuss. This means you are meant to address both the positive and negative aspects of cellulose being used as a raw material. In your case, you've only addressed a few positives - and even they require a little more detail (imo).

A few negatives, of the top of my head, could include: dedication of large tracts of land for the development of biomass means less land for other activities (such as farming). Also, although cellulose may theoretically present limitless possibilities, it is still too expensive to produce in large amounts. Though, if our current supply of petroleum is completely used, the price of cellulose may become competitive enough for it to be considered a viable replacement.

That would be what I would write if that question just so happened to pop up in an exam (in a more linear form, of course). If I've said something wrong or misleading, someone will most probably correct me.

 

[nml10]

Oh, I see. I had a feeling that it was too short.. Thanks for your feedback and suggestion.

Just one more thing, when you said my positive aspects require a little more detail, what exactly do you mean?

 

[UnrealAnchovies]

Oh, I see. I had a feeling that it was too short.. Thanks for your feedback and suggestion.

Just one more thing, when you said my positive aspects require a little more detail, what exactly do you mean?

Maybe detail wasn't the word. I'd say just try to write what you've gotten there in a more linear, coherent format.

 

[jamesfirst]

Advantages:

- Cellulose contains the basic carbon chain needed for the petrochemical industry to produce plastics. In order words it can replace the synthetic plastics we use today
- Cellulose is from biomass and biomass is basically plants. Therefore it is renewable. This is the biggest advantage and should always be listed
- Cellulose can be made into ethylene. Cellulose -> Glucose (by breaking the cellulose down using enzymes) -> Ethanol (fermentation) -> ethylene (dehydration using sulphuric acid)

Ethylene can be made into polyethylene

So basically Cellulose can replace the synthetic plastics which also reduces the amount of carbon emission from the industries.

 

[FCB]

Advantages:

- Cellulose contains the basic carbon chain needed for the petrochemical industry to produce plastics. In order words it can replace the synthetic plastics we use today
- Cellulose is from biomass and biomass is basically plants. Therefore it is renewable. This is the biggest advantage and should always be listed
- Cellulose can be made into ethylene. Cellulose -> Glucose (by breaking the cellulose down using enzymes) -> Ethanol (fermentation) -> ethylene (dehydration using sulphuric acid)

Ethylene can be made into polyethylene



So basically Cellulose can replace the synthetic plastics which also reduces the amount of carbon emission from the industries.

I honestly never thought enzymes were used to break down cellulose. I thought the only main option was cellulolysis or sulfuric acid and thats why it wasnt/isnt an economically viable option

 

[ohexploitable]

I honestly never thought enzymes were used to break down cellulose. I thought the only main option was cellulolysis or sulfuric acid and thats why it wasnt/isnt an economically viable option

Cellulose can be broken down by enzymes or heating in concentrated sulfuric acid.

 

[jamesfirst]

http://www.technologyreview.com/energy/20240/

Cellulose can be broken down by cellulases enzymes to produce Glucose

 

[Vincania]

I'd say you'd get a 1 or a 2 if you're lucky.

The question is a DISCUSS, therefore you have to present PROS AND CONS in your answer- and seeing that it's a 3 marker I'd assume the criteria would be a least 2 pros and 2 cons.

You've only addressed 1 and a half of the PROS section, meaning your answer is less than 50% of the required marking scheme.

I'd recommend you learn your verbs such as discuss, evaluate, assess, compare etc etc. These can be found on the proper BOS website.

 

[someth1ng]

I'd say - 1 mark.