How to Make Quick Lime and Slaked Lime

this is how to make quicklime out of seashells and then make slaked lime which is a good mortar and putty and paste . to make quicklime all the materials are as followed
1)a container of some sort
2)any lime product(i use seashells)
4)time i guess??
Quick lime is a corrosive acid so be VERY careful

Step 1: Quick Lime

mash up the seashells or other lime product into a powder
heat it on a stove (boiling it )
it should look acidy(i haven't done this before) and then, add in water let it react and slaked lime!!!
Note:seashells are calcium carbomate CACO3 and the quick lime is CAO and finally slaked lime CA(OH)2(aq)



    • Big and Small Contest

      Big and Small Contest
    • Toys Contest

      Toys Contest
    • Make it Glow Contest 2018

      Make it Glow Contest 2018

    12 Discussions


    2 years ago

    This is total rubbish! You need a fire or a kiln to convert calcium carbonate from shells or limestone into quicklime - high temperatures and a dry environment! Plus, quicklime is a strong alkali, not an acid. This article is wrong, dangerous and irresponsible and should be taken down.

    1 reply

    9 years ago on Introduction

    calcium carbonate (CaCO3) is insoluble in water you must drive off the carbon dioxide to get calcium oxide (CaO) it takes quite a bit of heat

    2 replies

    Reply 2 years ago

    You need to bake your limestone at about one hour at 900-1000 degrees Celsius, I've read elsewhere. Boiling will not get your limestone significantly above 100 degrees Celsius, so what you'll get will not actually be quicklime.

    For comparison and scale, most kitchen ovens don't make it past 300 degrees Celsius, professional pizza ovens never reach 500 degrees Celsius, aluminum melts somewhere above 600 degrees Celsius and low fire ceramics kilns work at ~1100 degrees Celsius. Glass starts to bend at about 1200 degrees Celsius.

    It seems egg shells contain very little minerals besides calcium carbonate, making them a very good material for making quicklime. (They do contain a significant amount of organic matter, but that's burned to gases in the firing process.) You could use squashed egg shells (so they can be compacted decently) placed in an iron box and the method outlined in this instructable for clay to try to make quicklime:

    After firing and cooling, spread a pinch of the white powder that results in a pan filled with water. If it splatters and bubbles upon contact (well, as much as that tiny amount can splatter and bubble), you got yourself some quicklime.

    Never mix a large quantity of quicklime and water indoors and fast. The reaction is violent and dangerous. Traditionally, where I live, this is done by digging a pit as deep as two meters, pouring the quicklime powder into it, then adding water until it coves the lime, being careful not to breed the resulting fumes. The fumes are basically just water, but the violence of the reaction will cause fine particles of quicklime to rise into the air, and these will continue the reaction inside your lungs, if you inhale them, and produce slaked lime, which is slightly toxic and corrosive.


    Reply 2 years ago

    wow this comment is actually more helpful than the instructable. I was hoping to make slaked lime at home for Nixtamalization. Thanks for the tip.

    ee geekEdbed

    Reply 3 years ago

    it appears to boil as the CO2 is released

    ee geek

    3 years ago

    CaO is a strong base... if you're dealing with any acids here (beyond identifying limestone) you're mistaken somehow.


    3 years ago

    After boiling my rocks my lime still looks alkalineny. Do I need to take more acid?


    4 years ago on Introduction

    If you are trying to help by answering questions you know nothing about, then you are actually doing us a disservice by giving bad advice. Please be aware of this next time.

    Never tell people how to do something if you have not done it yourself. It is dangerous

    If you want to help, you can point them to articles or films that may help them out instead.

    What does "acidy" mean?? You can not see acid, only pH testing strips, liquids can tell you what is and isn't an acid.


    5 years ago on Introduction

    "It should look acidy"? If you don't know, don't tell people things that are just not true, either.