What’s That – Biofuel Quality

Often, people assume that all biofuels are the same in terms of quality and performance. However, the two main biofuels used as sustainable alternatives to petroleum diesel—biodiesel and renewable diesel—are quite different. While both are sustainable alternatives for traditional diesel, they differ in production, chemical composition, and quality. In today’s What’s That Wednesday, we’ll explore the key differences in quality between biodiesel and renewable diesel. Both renewable options are excellent alternatives to traditional diesel, but understanding the fuel qualities of each will help you determine which one best suits your business needs.

What Are Biofuels

Before we dive into the quality differences between biodiesel and renewable diesel, it’s important to understand what biofuels are. Biofuels are renewable fuels derived from organic materials, collectively known as biomass. Biomass most commonly includes vegetable oils, animal fats, and even waste products like used cooking oil. These fuels serve as sustainable alternatives to traditional fossil fuels such as gasoline and diesel. By harnessing carbon already present in the biosphere, biofuels can greatly reduce greenhouse gas emissions when compared to petroleum-based fuels.

Production Processes

The primary difference between biodiesel and renewable diesel lies in their production processes and chemical properties, which influence their performance and compatibility with existing diesel engines. Biodiesel is produced through transesterification, a process where vegetable oils or animal fats react with methanol to create fatty acid methyl esters (FAME). This process retains oxygen in the biodiesel’s molecular structure, which impacts its chemical properties and storage requirements.

In contrast, renewable diesel is made through hydrogenation, which removes oxygen and results in hydrocarbon molecules almost identical to those in petroleum diesel. During hydrogenation, hydrogen gas is introduced to the feedstock under high temperature and pressure in the presence of a catalyst, such as nickel or palladium. This absence of oxygen significantly enhances renewable diesel’s quality and storage properties

Chemical Composition

The chemical composition of biodiesel and renewable diesel plays a key role in their quality and usability. Biodiesel contains oxygen, which can attract water and promote microbial growth. This makes biodiesel more prone to contamination and requires it to be stored separately from petroleum diesel. Biodiesel is typically blended with petroleum diesel in concentrations ranging from 5% (B5) to 20% (B20). Renewable diesel, as a pure hydrocarbon, is chemically indistinguishable from petroleum diesel. It does not attract water or support microbial growth, making it more stable and compatible with existing diesel infrastructure. Renewable diesel can be used as a complete drop-in replacement, often referred to as R99 or R100.

Performance and Quality

Several performance factors distinguish biodiesel from renewable diesel. Biodiesel has slightly lower energy content than petroleum diesel, while renewable diesel’s energy content is equivalent to or slightly higher than petroleum diesel. Biodiesel tends to gel at lower temperatures, making it less effective in cold climates. Renewable diesel, due to its hydrocarbon structure, performs better in cold weather conditions and resists gelling. Biodiesel’s oxygen content makes it more prone to degradation over time, whereas renewable diesel has a longer shelf life due to its absence of oxygen and resistance to microbial growth. Biodiesel provides excellent lubricity, reducing engine wear. Renewable diesel, though less effective in this regard, still meets industry standards for lubricity. From an environmental perspective, both biodiesel and renewable diesel significantly reduce greenhouse gas (GHG) emissions compared to petroleum diesel. However, biodiesel may result in slightly higher nitrogen oxide (NOx) emissions. Renewable diesel achieves substantial GHG reductions without increasing NOx emissions, making it a more environmentally friendly choice in many cases.

The Right Biofuel for You

Choosing between biodiesel and renewable diesel depends on your specific needs. Biodiesel is ideal for blending with petroleum diesel and enhancing lubricity, especially in applications that benefit from its cost-effectiveness and availability. Renewable diesel offers superior quality, performance, and compatibility with existing diesel systems. It is particularly well-suited for businesses seeking a drop-in replacement for petroleum diesel. Both biodiesel and renewable diesel play crucial roles in advancing sustainable fuel solutions. By understanding their unique characteristics, you can make informed decisions to optimize your operations and support environmental sustainability.

To find the best sustainable fuel solution for your business, consult an expert at Mansfield. At Mansfield Energy, we take pride in delivering top-tier products and services, supported by quality training and industry expertise. Discover how biofuels can work for you and keep your fleets running efficiently. You can learn more about Mansfield’s sustainable solutions and compare our renewable diesel with our biodiesel by accessing the Renewable Diesel & Biodiesel Comparison brochure.