Question

In detail, describe how waste engine oil can be reused in car again, its application and treatment method.

Answer 1

Waste engine oil can cause damage to the environment as it contains high pollutant materials. There are many methods used for recycling the waste oil such as vacuum distillation or use of sulfuric acid or acetic acid. Acid-clay has been used as a recycling method for used engine oil for a long time but it also produces large amount of by products. Solvent extraction has replaced acid treatment as improving oxidative stability and viscosity, temperature characteristics of base oils. Solvents like MIBK, Propane, acetic acid, etc are used. Membrane technology is also one of the method using hollow fibre membranes were used for recycling oils.

Optimum conditions for recycling used oil using acetic acid at room temperature and pressure. The process requires mixing at room temperature, settling, centrifugation and finally mixing with kaolinite. The oil is potential to be used in cars engine. The use of glacial acetic acid is almost no reaction with base oils, lower amount of additives are required.

In this method, glacial acetic acid is mixed in 7.4 percent (vol), settling is carried out for 24 hours followed by centrifugation for 1 hour to separate base oil from contaminants. The separated base oil is mixed with kaolinite at a ratio of 1 mL oil to 4g kaolinite. It is added to remove colour and smell which results from oxidation of some components in oil. This is achieved by heating it to 250 C, followed by centrifugation for 30 min.