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Catalyst needed to create dustless chalk


perfect chalk

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Please keep in mind that I am an MBA student whose chemistry knowledge in chemistry in seriously lacking

 

Background:

As apart of my graduate program we travel to a developing country (Rwanda in my case) and help local social enterprises to develop their business. The company that my group is working with is called Perfect Chalk and they create chalk for local public schools. Since 83% of the populations without a stable electrical grid, chalk is the main teaching tool in this country.

 

Problem:

This company uses 3.5 L water and 3.5 kg calcium carbonate (limestone) to create a batch of 600 single pieces of chalk. However these pieces are often porous causing it to break easily and to produce potentially health hazardous dust particles. Its imported competitors have created a dustless chalk that is of a much higher quality, using essentially the same materials plus an additional catalyst that is used to speed up the chemical reaction thereby creating a paste that contains much finer and tightly packed particles, according to the company current chemist (keep in mind that he has the equivalency of a high school education, and therefore might have the necessary knowledge). My question is what could that catalyst possibly be

 

Thank you for your help

 

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http://www.madehow.com/Volume-1/Chalk.html

Almost all chalk produced today is dustless. Earlier, softer chalk tended to produce a cloud of dust that some feared might contribute to respiratory problems. Dustless chalk still produces dust; it's just that the dust settles faster. Manufacturers accomplish this by baking their chalk longer to harden it more. Another method, used by a French company, is to dip eighty percent of each dustless chalk stick in shellac to prevent the chalk from rubbing off onto the hands.

 

Perhaps it's not an additive, but rather a change in the manufacturing process. Try baking longer.

 

This reminds me of German asphalt for roads. It's not fundamentally any different, but the Germans let asphalt cure for 90 days before letting cars on it. It sets up like iron, and it's guaranteed to be pothole-free for ten years. You only need to add patience.

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This company uses 3.5 L water and 3.5 kg calcium carbonate (limestone) to create a batch of 600 single pieces of chalk. However these pieces are often porous causing it to break easily and to produce potentially health hazardous dust particles. Its imported competitors have created a dustless chalk that is of a much higher quality, using essentially the same materials plus an additional catalyst that is used to speed up the chemical reaction thereby creating a paste that contains much finer and tightly packed particles, according to the company current chemist (keep in mind that he has the equivalency of a high school education, and therefore might have the necessary knowledge). My question is what could that catalyst possibly be

 

You should verify competitors product whether it's Calcium Carbonate CaCO3, or whether it's Calcium Sulfate CaSO4. It can be either of them mixed together, in various percentages.

 

Calcium carbonate undergoes reaction with Acetic Acid:

CaCO3+2CH3COOH->Ca(CH3COO)2+CO2+H2O

It releases Carbon Dioxide CO2 gas bubbles and water, and creates Calcium acetate.

 

So, first verify product of your businessman, dissolving it in acetic acid,

then repeat the same with competitors product.

If they were pure Calcium Carbonate, there should be no significant amount of remains.

Calcium acetate is quite good soluble in water 34.7 g/100 mL @ 20 C.

 

For 100 grams of Calcium Carbonate, you will need ~120 grams of Acetic Acid, which is approximately 1200 mL of Acetic Acid 10% by volume.

 

Since 83% of the populations without a stable electrical grid,

 

Shouldn't you in that case think how to make electricity in the first place?

 

Solar panel for $250-$300 can give you ~200 Watts, and working "forever", say 30 years, without any additional serious costs..

That is $0.02 (2 cents) per day of working.

https://www.google.com/?gws_rd=ssl#q=solar+panel+200w

Edited by Sensei
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@ phi for all, thank you for reply, that is actually one of the tests we will be running later today. I will update you on the results when we do so

 

@sensei, thats a great idea that we would have not even thought of, and will get to working on today. As for the electricity component, we have a group working with great lakes energy (a Rwandan solar panel manufacturer) to hopefully provide feasible and cost effective solutions to the aforementioned problem. While it may not provide a perfect long term solution it will at least be a band-aid solution until the proper infrastructure can be installed.

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