In recent years, sodium methylate has become the catalyst of choice for many biodiesel producers around the world. The benefits of using sodium methylate as a catalyst include higher biodiesel yield, lower purification costs and more consistent quality than what can be achieved using caustic soda (sodium hydroxide) or caustic potash (potassium hydroxide).

As U.S. biodiesel production levels rise above 250 MMgy, the industry is driving hundreds of millions of gallons of feedstock, catalyst and finished biodiesel to be shipped, handled and stored across the United States. The health of employees and the continued success of the industry require that this be done as safely and efficiently as possible. If handled improperly, many of the products and materials used in the day-to-day operation of a biodiesel facility can be harmful to people, property and the environment.

We all want employees to go home from work as healthy as when they arrived in the morning. This applies to everyone from office personnel to plant operators who handle hazardous chemicals and oversee dangerous production processes. Safety must always be "top of mind" for anyone working in a manufacturing environment.

Sodium methylate's safety and handling guidelines are a mixture between those for methanol and caustic soda. Sodium methylate has been safely used for decades in the manufacture of pharmaceuticals, food ingredients and crop protection agents. It has proven to be a very effective catalyst for biodiesel, but like methanol, it is classified as a hazardous material and, like caustic soda, it is corrosive. Therefore, it requires specific attention to handling and storage.



Packaging and Storage
When purchasing any chemical, it is important to ensure that the product is shipped and stored in a safe, approved container. For sodium methylate, the three best options are isotainers or bulk tank trucks, steel drums with non-removable heads and totes composed of polyethylene bladders surrounded by steel cages.

Drums and totes should be stored in a dry, well-ventilated area, protected from heat and direct sunlight. Partial containers should be blanketed with nitrogen to avoid moisture exposure, and empty containers should not be reused. Drums and totes should not be heated. If heating is necessary to allow emptying, the drum should be equipped with a pressure relief valve and the temperature of the heating device should be controlled. Any released vapors should be properly vented to a scrubber or vapor destruction system.

Isotainers or bulk trucks are most appropriate when sodium methylate demand is greater than 45,000 pounds per month. Closed systems are best for transferring sodium methylate to a storage tank. The isotainer manway should never be opened during unloading, as this can introduce moisture and cold air. Moisture decreases the quality of the product and cold air can cause the product to precipitate out of solution in methanol. Ideally, a nitrogen purge line should be connected to the isotainer to blanket the methylate and replace the volume of sodium methylate solution being pumped from the isotainer. While adding nitrogen to this system, handlers should adhere to the pressure limitations of the isotainer. Use of a pressure relief device set for the rated pressure of the isotainer would prevent vessel rupture.

Introducing moisture into the sodium methylate feed system can decrease product purity and increase the chance of corrosion over time in carbon steel systems, especially in heated storage tanks. Stainless steel storage tanks are recommended. If carbon steel tanks are used, an annual preventive maintenance program should be implemented to check for corrosion, especially near heating devices. Storage tanks should be vented according to local, state and federal regulations. Note that the vents should prevent entry of oxygen, carbon dioxide and moisture into the vessel. A constant purge of dry nitrogen is recommended. Vapors emanating from storage tanks should be controlled in compliance with site air permits.

Finally, all isotainers delivered to a facility should arrive with security seals on the valves and fittings. If a seal is missing or broken or the seal number does not match the number on the shipping papers, the supplier should be contacted prior to unloading.

Time spent learning safe handling practices and improving safety measures are good investments in the health of employees and the stability of a business. Sodium methylate suppliers are an excellent resource to draw on for safety information and suggestions.

A good checklist for safe handling should include the following:
› Sodium methylate should be stored and transported in a closed, dry system.

› Sodium methylate should not come into contact with water, acids or acid-forming substances.

› The area in which sodium methylate is stored must be rated for handling of flammables, and sources of ignition should be avoided.

› A vapor recovery system should be in place to control vapors or mists.

› Proper personal protection equipment includes neoprene gloves and boots, coveralls, goggles and a face shield. The personal protection equipment should be worn whenever the possibility exists for direct contact with the material. Contact with the eyes, skin and respiratory tract should be avoided.

› Liquid solutions are flammable and corrosive.

› Vapors are heavier than air and may travel along the ground or floor to a distant source of ignition, causing a flash back.

› Only non-sparking and non-static tools should be used. All equipment should be grounded.

› Eye wash stations and safety showers should be readily accessible.

BASF, Responsible Care
As the world's leading chemical company, BASF Corp. has a strong commitment to responsible care. BASF conducts business and operates facilities in a safe and environmentally responsible fashion. The company also supports its customers and suppliers to ensure the safe and environmentally sound handling of its products, and minimize the impact of its operations on society and the environment during production, storage, transport, use and disposal of its products.

To obtain more information about the BASF portfolio of catalysts for biodiesel, visit www.basf.com/alcoholates. For more information about environmental health and safety at BASF, visit www.basf.com/alcoholates/the_lab.html, or contact BASF Technical Manager Bill Atkins at william.atkins@basf.com or (724) 538-1204.

Mike Schulz is a product manager for BASF Corp. Reach him at mike.schulz@basf.com or (724) 538-1362.

The claims and statements made in this article belong exclusively to the author(s) and do not necessarily reflect the views of Biodiesel Magazine or its advertisers. All questions pertaining to this article should be directed to the author(s).