A review study on the use of dimethyl ether in diesel engines: effects on CO2 emissions

Emissions from vehicles and other fuel combustion systems can alter the composition of the atmosphere and augment its capacity to absorb heat. These gases, which are effective at trapping heat, are known as greenhouse gases and include all gases found in vehicle emissions. Reducing the emissions of carbon dioxide (CO2) has become an urgent necessity around the world, and many countries have imposed limits on their CO2 output. Using biofuels in automotive engines is an effective way of reducing greenhouse gas emissions. The CO2 emissions emitted from the combustion of biofuels are absorbed as trees and plants grow. Biofuels can be used either as pure fuels or blended with conventional fuels. Most research has declared that the most effective way to reduce greenhouse emissions is the use of various biofuels. Therefore, it is essential to assess the outcomes of research regarding alternate fuels or fuel additives to determine their proper utilization. Using of diesel engines can also help reduce CO2 emissions as they emit less CO2 emissions than gasoline engines. This review study investigates the effects the using of dimethyl ether on CO2 emissions in diesel engines. The results showed that CO2 emissions decrease when using the pure DME and DME blends with diesel and LPG fuels due to the oxygen content and the lower carbon to hydrogen ratio of DME. The decrements in CO2 emissions for pure DME, diesel–DME blends and LPG–DME blend are about 5.2–18.3%, 3–41.6% and 10.6–16.4%, respectively.