Their is 42 gallons to a barrel and 7.33 barrels to a metric ton so 500 gallons / 42 = 11 barrels so 11/7.33 = 1.5 Metric tons

500 gallon equals 1892 litre and and 1 metric ton of canola oil equal 1000 ltr so its simple, 500 gallons equals 1.89 metric tons if I am not wrong.