Using Mustard Oil for Biodiesel

The “Mustard Bug” is not a pest, but a VW that runs on biodiesel made from mustard oil at the University of Idaho where they are researching mustard oil’s energy potential for biodiesel fuel.

Mustard flowers. Photo: Riyaas; Wikimedia Commons.



Mustard seed oil is not currently a common biodiesel feedstock, but because it has the potential to be a cheaper feedstock than the two most common oilseeds …

Saponification in Biodiesel Production

Introduction to Saponification

Saponification is a chemical reaction that involves the production of a metal salt or soap. The reaction involves the attack on a methyl ester, free fatty acid, triglyceride, or other glyceride by a hydroxide ion, OH.

The hydroxide ion implies the presence of water in the system. If water could be eliminated, then there would be no soap formation. However, this is a practical impossibility. There is always some water present, and there will always be …

Reactors for Biodiesel Production


Three general types of reactors are used for biodiesel production: batch reactors, semi-continuous-flow reactors, and continuous-flow reactors.

The batch process is inexpensive, requiring much less initial capital and infrastructure investment. It is flexible and allows the user to accommodate variations in feedstock type, composition, and quantity. The major drawbacks of the batch process include low productivity, larger variation in product quality, and more intensive labor and energy requirements.

The semi-continuous process is similar to the batch process except that …

Processing Oilseeds and Oil for Biodiesel Production

How Should Oilseeds Be Processed before Pressing?

Extraneous material should first be removed from the harvested crop seed by screening. This is particularly important to ensure that materials such as small stones are removed prior to crushing and extraction. The seed should also be passed over a magnet to remove metal pieces.

Processors sometimes heat the seeds prior to processing to increase the oil yield. When pressing for fuel production, it is possible to use engine exhaust to warm the …

Rapeseed and Canola for Biodiesel Production

Oil from rapeseed or canola seed, the edible crop varieties, is used in biodiesel energy production. The oil has a low cloud point so it gels at lower temperatures than many other feedstocks.

Canola plants growing at Tennessee State University research farm. Photo: Jason de Koff, Extension Assistant Professor, Tennessee State University.



Oilseed Handling for Biodiesel Production


Many types of oil-bearing seeds and nuts can be used to make biodiesel. Commonly used feedstocks for the production of biodiesel include soybean, rapeseed/canola, used (waste) vegetable oils, and tallow/lard (animal fat). Mustard biodiesel is being studied at the University of Idaho, and Montana State University is conducting research on camelina for biodiesel production. Safflower, sunflowers, corn, and even hazelnut produce oil that could be used for biodiesel. Warm-climate tree oils such as palm oil, coconut, and …

Handling Strong Bases in Biodiesel Production

Sodium and Potassium Hydroxides/Methoxides

Used to catalyze the transesterification reaction, sodium and potassium hydroxide are extremely corrosive.

The hydroxides are dry flakes or pellets and must be dissolved in methanol, which produces “methoxides” concentrated in methanol. The dust from the hydroxides is an airway irritant and will burn unprotected skin and eyes, especially when handled manually. Dissolving the hydroxides in alcohol is an exothermic reaction and can generate a considerable amount of heat. Stirring the liquid in an open container …

Handling Strong Acids in Biodiesel Production

Sulfuric and Hydrochloric Acids

Acids may be used in treating high free fatty acid (FFA) feedstocks, neutralizing base catalyst and splitting soaps in the washing process, and/or in treating the crude glycerin by-product. Acids are colorless and can be extremely damaging to all body tissue. Acids cause rapid tissue destruction and serious chemical burns. Their vapors can cause eye, nose, and throat irritation; shortness of breath; pulmonary edema; or other serious ailments. Workers should wear acid-resistant protective clothing and gloves, …

BQ-9000 Program for Biodiesel Producers


BQ-9000 is a voluntary quality assurance program created by the National Biodiesel Board. For details, visit the National Biodiesel Accreditation Program BQ-9000 program

The BQ-9000 program certifies biodiesel producers, marketers, and testing labs. The BQ-9000 program starts with the ASTM D6751 standard for biodiesel and adds a quality systems program to make sure biodiesel is sampled, tested, stored, blended, shipped, and distributed in a way that maintains high quality.

The incentive for a producer or a marketer to become …

Methoxide Catalysts in Biodiesel Production

The methoxide ion, OCH3, is the active catalyst for the production of methyl esters. It is this chemical unit that attacks the triglyceride molecules and produces the methyl esters. It is regenerated at the end of each reaction step when a hydrogen ion is stripped from a nearby methanol molecule.

If ethanol is being used, then the corresponding catalyst is called ethoxide, OCH2CH3.

Most small producers create the methoxide ions needed for …