i clean my oil with a centrifuge for my SVO jetta


but would adding salt (large tablet size) i think its used in pools; added to the oil while heated and CF to bring down the acidity and help in the BD process.

or

is there anything else that can be added to the oil while CF'ing to lower acidity?

Do a search for "caustic stripping" or "lye stripping" or variants of these in both the "biodiesel" and "straight veg" forums, this process dissolves the caustic in water which is then mixed with the oil, it will convert the Free Fatty Acids that cause your high titration numbers into soap that will drop to the bottom of the oil. it has been discussed a lot in the past to reduce the titration number of veg. You can us about any caustic, baking soda, washing soda, or lye, all work. I use baking soda but it will take a few days to work completely, lye will work over night but you need to do a titration so you don't add to much lye, no need to titrate with baking soda. Baking soda is a mild caustic so it won't increase the amount of acid by cleaving off more Free Fatty Acids from the oil molecule like the much more caustic lye will, you can't use too much baking soda so no titration is needed.