Nanoparticles’ role in improving fuel efficiency and reducing emissions

Dr. Raj Shah, Dr. Steve Nitodas, Mr. Nicholas Douglas and Mr. Nathan Aragon
In its natural form, energy has contributed significantly to humanity’s progress over the years. However, due to an unchecked increase in pollution, new alternatives to fossil fuels need to be developed. Currently, new research into fuel additives, including those with nanotechnology, such as nanofluids, show promise in reducing pollution and offer sustainable fuel options. The purpose of this article is to explore how nanoparticles function as fuel additives for improving fuel efficiency and controlling pollution.
The impact of nanoparticles as fuel additives has shown serious improvements but also implications for the energy sector. The studied nanoparticles included several elements, such as zinc, aluminum, and boron metalloids. These nanoparticles were then emulsified with various fuels, primarily diesel, and used for testing in standard engines 1 . Fuels infused with nanoparticles show improved calorific value and cetane number of diesel and biodiesel fuel. However, viscosity, flash point and density of fuel can be slightly increased. In addition, the concentration of nano fluid additives must be kept under an upper limit to avoid higher CO emissions.
As for the efficiency of the engines, researchers found that nano-additives improve fuel and engine efficiency. Both brake specific fuel consumption (BSFC), which is the rate of fuel consumption per unit of power used, and brake thermal efficiency (BTE: how well an engine converts heat from fuel to mechanical energy) were improved by varying margins. For example, zinc oxide (ZnO) additives exhibited a decrease in BSFC from 0.278 and 0.272 kg/kWh, and an increase in BTE from 28.8 to 29.96 kg/kWh when the particle size doubled 1 . These results show promising evidence of efficient engines with nanoparticle fuel additives in normal diesel engines.
Alumina (Al 2 O 3 ) additives also provide enhancements to fuel combustion and efficiency in engines.  Alumina additives blend with biodiesel and other renewable fuels to increase efficiency in engines. When under combustion, alumina nanoparticles form into aluminum (I) oxide and then aluminum metal. 2 In both stages, oxygen released goes to fuel combustion, contributing to an increase in complete combustion, therefore, leading to more efficient engines.  Specifically, alumina additives work to improve brake thermal efficiency and brake specific energy consumption (BSEC). Researchers found a decrease in BSEC from regular diesel fuels, with a difference of about 10 MJ/kWh at 25% engine load 2 . This difference diminishes as load increases due to higher fuel demand for optimal performance. For BTE, significant improvements on engine performance were demonstrated. In testing, differences in BTE of approximately 5% between diesel fuels and alumina-infused biodiesels were observed, increasing as load increased. 2 TF20- an alumina additive...