I am new to making my own biodiesel but have made what i think are 2 successful 20gal batches. Someone please correct me if i am wrong. I have 20gal of oil and i add 4 gal of methanol. i add the appropriate amount of KOH per my tiration tests which are usually between 2-3. i use a base amount of 7g/L. I heat to 120F and mix the methoxide for 45min. i let settle for at leat 24hours. i thought you were supposed to get only 10% glycerin which is about what i have been getting. i am draining out about 2.5 gal of glycerin. I run the rest through a purolite drywash filter and a regular fuel filter before going into the tank. I have been reading on the forums about you should get 80-95% yeild of your batch. Is that before or after you add the meth? Thanks for any feedback

Hello TFG, welcome to the forum

This is predominatly an Australian forum so measurement in metric is best.

Check the purity of your KOH. A lot of it is 90% purity which means you will need to adjust your Base amount to 7.8g kOH per litre

45 minutes is probably a bit short on your mixing. What type of reactor do you have? If in doubt mix longer rather than shorter.
You can leave it settle as long as you like. I like overnight.
The amount of "glycerine" depends on a number of things including the titration of the biodiesel.

A yield of 80- 95% is compared to the amount of Oil being reacted.