2,6-Di-Tert-Butyl-P-Cresol, known by the abbreviation BHT, steps into the spotlight as a widely used synthetic antioxidant with the molecular formula C15H24O. Sometimes called butylated hydroxytoluene, this substance carries the HS Code 2907199090 for international trade, marking its significance in global chemical commerce. I’ve run into BHT plenty of times in lab work, where it’s taken the form of white, crystalline flakes or powder. You usually see it as a solid, but it can also come as crystalline pearls, and with enough solvent, it dissolves into a clear liquid solution. The density usually falls near 1.05 g/cm³, putting it in the same range as some common plastics or dense resins. Its specific molecular weight clocks at about 220.35 g/mol, giving it some heft for a relatively simple phenolic compound.
The structure of 2,6-Di-Tert-Butyl-P-Cresol features a phenolic ring with bulky tert-butyl groups locked at the 2 and 6 positions, and a methyl group at the para position. This arrangement actually shields the reactive phenolic hydroxyl, making BHT much more stable against oxidation — a property that explains why it’s a favorite for inhibiting oxidation in products like rubber, plastics, and even foodstuffs. The crystalline and flaky nature comes from how these large tert-butyl groups push apart neighboring molecules. In my experience handling BHT, it pours similarly to coarse sugar when in crystal form, yet compresses readily if treated in a powder mill. There’s a faint, characteristic odor — not spicy, not sweet — almost waxy and neutral, fitting for a chemical designed to avoid unwanted reactions.
In the materials marketplace, BHT often arrives in solid form: flakes, compressed pearls, or free-flowing powders. Lab supply catalogs tend to list BHT with purities ranging from 99% to 99.5%, with a melting point between 69 and 71°C. These specifications matter when trying to match a raw material to a use case. Flakes and crystals suit weighing out small, precise quantities in the lab. Powders find their way into manufacturing lines and blending hoppers. Even as a concentrated solution in various solvents, BHT keeps its chemical identity and efficacy up to moderate temperatures. In larger material bags, it handles as a non-caking powder when kept dry, but ambient humidity can cause some clumping, so manufacturers recommend sealed containers and desiccant packs if storage continues for more than a few weeks.
Anyone working in plastics, fuel, or food knows BHT’s knack for stopping oxidation — it acts like a chemical “bodyguard” for ingredients facing heat, air, or light. Its primary role as a raw material involves preserving color, flavor, and structural integrity, extending shelf life in finished products. Polyolefins, elastomers, lubricants, and biodiesel depend on it to survive the stress of transport and storage. Even as a food additive, BHT holds a GRAS (Generally Recognized as Safe) status under regulated limits, and I have seen it on the label of cereals, chewing gum, and cooking oils. The chemical brings some flexibility to formulation scientists; a small amount keeps volatile ingredients from spoiling, and yet it resists breakdown during storage, ensuring a consistent dose of protection. Some specialty grades target pharmaceutical or cosmetic applications, made under stricter controls to minimize trace impurities.
BHT blends convenience with responsibility. While it behaves as a stable solid at room temperature and resists ignition (flash point around 127°C), manufacturers still mark it as hazardous for its potential to irritate the eyes and skin, especially when dust forms during handling. Prolonged or repeated inhalation of fine powder brings health risks; in my early career, I learned quickly to wear gloves and dust masks in industrial settings. On larger scales, storage requires clear labeling and separation from oxidizing agents or acids. Spill cleanup involves sweeping or vacuuming dry solid; water rinses drive BHT into drains, where it can linger in the environment unless properly treated. Research shows that aquatic toxicity exists, and some bioaccumulation may occur, so environmental controls play a central role in responsible handling. Workplace exposure limits and hazard sheets spell out the specifics, underscoring the need for local exhaust ventilation, secure storage, and controlled disposal through approved waste handlers.
BHT has grown from a niche laboratory chemical to a staple raw material for multiple industries. Producers refine their processes to deliver high-purity, consistent material, often starting from p-cresol and isobutylene under acid-catalyzed conditions. Supply chains revolve around chemical hubs in Asia, Europe, and North America, regulated by international trade codes and strict customs documentation. Price volatility tracks the cost of phenol feedstocks and energy, creating logistics challenges. For users seeking a stable supply while keeping regulatory compliance and sustainable practice in mind, planning ahead with long-term contracts and supplier audits can cut risk. Some companies now offer greener synthesis pathways to reduce byproducts and optimize yields, although traditional manufacturing still dominates the bulk market.
Concerns about long-term exposure and environmental buildup keep BHT under scrutiny, especially in food and pharmaceutical use. Some countries restrict its use or require detailed labeling, pushing manufacturers to reexamine how much and how often BHT gets added. Alternatives do exist, like tocopherols or rosemary extract, but these can cost more or lack the same shelf life boost. I remember brands announcing transitions away from traditional antioxidants a decade ago, but many circled back due to the reliability of BHT under tough conditions. Integrated supply chains now pay closer attention to the full life cycle of chemical additives, exploring recycling and recovery strategies for plastic and tire waste. Improving transparency through proper documentation, research on safe exposure limits, and ongoing monitoring could help manufacturers and end users strike a balance between efficacy, safety, and sustainability — an effort that calls for both technical innovation and clear communication with the public.
