This soap test kit is a way to easily test for soaps in Biodiesel and in methanol. Everything you need is included, a liter of 99+% Isopropyl Alcohol, 18ml Bromophenol Blue, 120ml 0.01 (N) HCL, 5 each 250 ml disposible beakers, a pipette pump, calculator and three pipettes. Detailed instructions included. The kit and instructions are based on the instructions in the Biodiesel collaborative website and is the method used by most commercial producers. The kit contains enough isopropanol for 10 tests, Bromo Blue for about 20 tests and HCL for 75 to 100 (depending on the soap levels). Refills and for these products are available. If buying your Isopropyl Alcohol locally be sure it is 99+%, 91% rubbing alcohol will not give acurate test results because it may not be PH neutral.
You can test your washed biodiesel to ascertain that it is done washing, or if it needs another wash. Biodiesel needs to be less than 60 PPM soap to pass ASTM standards. It's also the only positive way to test for soap in your methanol used to flush the ion exchange resin in dry wash columns to ensure they've been properly cleaned. By testing the final wash product you will know, if the soap level is low, you have effectively flushed the particulates from your resin and it is ready to go back in service.
