AdBlue or diesel exhaust fluid (DEF) is an aqueous solution of urea, effective in reducing Nitrogen oxide emissions. It is a popular fluid mix for diesel and gasoline fuel-based vehicles. AdBlue is used in selective catalytic reduction (SCR) and exhaust gas recirculation (EGR) to reduce the emission of nitrogen oxides. The exhaust gasses are treated with AdBlue in the exhaust pipe and then...