Quality Criteria in Fuel

The quality of a fuel is defined as a set of properties and related limits that are necessary to ensure that it performs well in engines. In addition, this definition includes the minimum requirements and suitability for use specified in these specific features. Comparison of gasoline, ethanol, diesel and biodiesel specifications in different countries and regions is defined as nonconformity when they are different.

If a fuel does not meet any of its specifications, it is called non-conformance, which means that the fuel is unsuitable for use. Non-compliance is not always caused by adulteration, which is the deliberate and illegal addition of lower-cost substances to a fuel, often through tax evasion, in order to increase the profit margin illegally, reduce tax revenues and result in unfair competition. It is responsible for the damage to the environment and the increased wear and tear of vehicle engines. In fact, a fuel oil can be purified and still remain within its specifications, in which case the only detrimental effect is on tax revenues. Detecting adulteration of fuels is a challenge because impurities often contain compounds already present in the fuels themselves.

While illegal fuel additive practice can impair the quality of the fuel, it can also cause environmental pollution that contaminates gases and particulate matter, because the combustion process is affected and results in higher emissions of acid rain-causing pollutants and compounds such as NOx and SOx, resulting in highly suffocating CO.

The biggest harmful effect of fuel adulteration is on vehicle performance. In 2006, it was determined that approximately 95% of vehicle repairs were directly or indirectly caused by poor fuel quality in São Paulo, Brazil. Indeed, it has been calculated that the disgust for fuel cost Brazil more than $ 1 billion that year, and $ 400 million was lost in tax revenue, affecting both local and federal budgets. According to the Brazilian newspaper Estadão, a study conducted by the Getúlio Vargas Foundation in 2017 revealed that 4.8 billion reais are lost each year in the fuel industry due to money laundering and tax evasion and have serious knock-on effects on the economy as a whole.

According to ANP, the agency responsible for monitoring fuel quality in the country, it can be mixed in various ways, such as adding ethanol to gasoline above the maximum allowable limit or illegal addition of light and heavy aliphatic and aromatic solvents, except for its own gasoline components.

In Brazil, gasoline and ethanol are both mixed with methanol, which is not allowed to exceed 0.5% v / h due to its toxicity, but its low price makes it an attractive impurity. Meanwhile, the main inconvenience found in diesel in Brazil is the failure to comply with the correct amount of biodiesel set by ANP at 10% v / v. Petroleum products such as fuel are extremely important inputs for economies, industries and basic daily activities around the world. Its importance to governments means that they tend to be heavily taxed, whether due to geopolitical reasons, armed conflicts or economic factors, which increases their costs to consumers. As a result, adulteration has become a common practice in a wide variety of regions such as South America and South Asia.

Kerosene is subsidized in India, which makes it particularly popular for mixing gasoline with other products such as naphtha, rubber solvents, aromatics, ethanol, light and heavy aliphatic solvents and lubricants. In 2018, the East African Petroleum Institute announced that 75% of 33 million liters of kerosene consumed every month contaminated diesel and gasoline. In his statement, 5 million liters are used each month for lighting and cooking alone. Although cases of contamination of gasoline with acetone and sec-butyl acetate were reported in Vietnam and China in 2016, this practice is now less common in Vietnam with the introduction of new limits for ketones in gasoline properties. In China, gasoline is often mixed with substances such as naphtha, ethanol, methanol, and even silicone oil or silicon-containing waste chemicals.

In Australia, the Ministry of Environment and Energy has regulated the Fuel Quality Standards Act 2000, which regulates and provides standards for fuel quality in the country. In Europe, mandatory quality requirements for automotive gasoline and diesel are determined in Directive 98/70 / EC. In the United States, ASTM International has published standards for all types of fuel. Petroleum Products, Liquid Fuels and Mineral Oils Committee D02 is responsible for determining the fuel quality standards. Meanwhile, there are two standards for fuels in Japan, the mandatory standards set by the Central Environment Council under the Ministry of Environment and the Japanese Industry Standards.

The first is legal requirements and regulates the Quality Control Act for Gasoline and Other Fuels, which has been in force since April 1996. Additional Materials are included according to the tables showing gasoline, diesel, ethanol and biodiesel specifications for each country or region. Analytical methods for monitoring gasoline and diesel purity, density, distillation curve, octane rating, vapor pressure, etc. using physicochemical methods and chromatographic and spectroscopic methods. It has been the target of a recent review highlighting the identification of such different characteristics.

Non-destructive analytical methods for determining non-specific biodiesel levels in diesel-biodiesel blends and blending are also discussed in a new review focusing on first-order multivariate calibration models. In this section, different colorimetric techniques that can be used in fuel quality control, especially simple, fast, low-cost methods that have the potential to detect fuel pollution in the field are discussed.

These tests describe an unmeasurable archive of point tests used in organic and inorganic analysis that could be an inspiration for the development of other colorimetric analyzes. Similarly, the solvatochromic effect of dyes and fibers used as probes or sensors has been used to detect water or ethanol in biodiesel and gasoline in diesel-biodiesel blends, and even to detect adulterants in gasoline.