N-Butanol’s roots stretch back to the early 20th century when German chemist Ferdinand Gabriel first described it in the 1860s, but it wasn’t until the rise of industrial fermentation that it started gaining commercial traction. By the time World War I rolled around, Chaim Weizmann perfected the ABE (acetone-butanol-ethanol) fermentation method using Clostridium bacteria, turning the n-butanol story into something more than just lab talk. Paints, lacquers, rubber, and explosives—all needed solvents and plasticizers, and n-butanol fit the bill. Today, most production comes through petrochemical routes, though fermentation never quite slipped out of view.
N-Butanol stands as a four-carbon straight-chain alcohol. It bridges the gap between smaller alcohols that evaporate fast and higher ones that tend to get greasy. Here’s a chemical with just the right balance—miscible in organic solvents, slightly soluble in water, and boasting a moderate boiling point. Industries reach for it as both a solvent and a chemical building block, feeding everything from plastics and coatings to pharmaceuticals. Production volume stretches into the millions of tons every year, with big players refining it by hydroformylation of propylene.
N-Butanol presents itself as a clear, colorless liquid with a sharp, slightly sweet odor you won’t miss in a lab. Its boiling point hovers around 118°C, which keeps it liquid at room temperature but makes distillation manageable. Density clocks in near 0.81 g/cm³, less than water—so it floats. It resists freezing until -89°C and flashes if you heat it past 35°C. With a vapor pressure of about 6 mmHg at 20°C, open containers give off enough vapor to smell but don’t turn the room into a fume-filled hazard in a hurry. It reacts slowly with oxidizing agents, and prolonged exposure to strong acids or bases kicks off esterification or etherification. The hydroxyl group on the end gives it plenty of chemical flexibility—sometimes helpful, sometimes a headache.
Labels on drums tell you most of what you need to know: chemical formula C₄H₉OH, UN number 1120, proper shipping name n-Butanol, CAS number 71-36-3. Purity levels for industrial use typically sit above 99%, and buyers like to see specs on moisture content, color (measured in Hazen units), and sometimes on aldehydes and acids, especially for sensitive coatings or pharmaceuticals. Safety Data Sheets carry the usual warnings about flammability and skin/eye irritation, plus tips on handling spills and fires. For transport, n-butanol rides as a Class 3 flammable liquid, needing sturdy containers with pressure release.
Hydroformylation, sometimes called oxo synthesis, powers most modern production. It starts with propylene, a byproduct of oil refining or natural gas cracking, and treats it with synthesis gas—a mix of hydrogen and carbon monoxide—under pressure and heat. The intermediate, butyraldehyde, gets reduced to n-butanol through catalytic hydrogenation. A handful of smaller outfits still practice fermentation using corn or sugar feedstocks, relying on specific bacteria to crank out the alcohol, but this route typically comes with lower yields and higher costs. Still, fermentation traditions stick around in biofuel research circles.
N-Butanol stands out for its ability to step sideways or up the value chain via easy chemical tweaks. Esterification with carboxylic acids produces things like n-butyl acetate—a staple in paints and adhesives for its low odor and smooth spreading. Oxidizing n-butanol opens the door to butyraldehyde, launching further reactions to yield plasticizers, solvents, or even agricultural chemicals. Halogenation, etherification, and dehydration all turn n-butanol into something new—sometimes planned, sometimes not. Chemists lean on it for its straightforward structure and reliable reactivity.
Depending on the setting and supplier, n-butanol may show up as 1-butanol, butyl alcohol, or n-butyl alcohol. It shares the shelf with isomers like isobutanol, sec-butanol, and tert-butanol, though these carry different physical traits and safety challenges. Trade names are rare, but drum labels and invoices might say "normal butanol" or abbreviate it as NBA. Confusion can sneak in if a vendor switches to a different isomer, so most buyers check chemical identifiers as well as the big letters on the label.
Handling n-butanol means respecting its flammability and the risk it brings to skin and eyes. Eye protection, gloves, and splash-resistant clothing count as standard in the lab or on the shop floor. Storage stays cool, dry, and well-ventilated, far from sparks and heat sources. Spills spread quickly, so absorbent granules and ventilation come in handy. Fire response needs foam, carbon dioxide, or dry chemical—never water, which spreads the burning liquid. Workplace guidelines from OSHA recommend threshold limit values that keep exposure under control, but accidents and chronic fumes still show up in case reports. A small spill needs a quick cleanup before vapors build, and industrial hygiene monitors for both inhalation and skin exposure.
Paints and coatings claim a big slice of the n-butanol pie, counting on its slow evaporation for smooth finishes. Inks, adhesives, and cleaning fluids turn to it for the same reasons—easy blending, solid solvency, and manageable evaporation. Chemical manufacturers use n-butanol as a feedstock for butyraldehyde, which branches into plasticizers like dibutyl phthalate. Pharmaceuticals and perfumes treat it as a carrier or intermediate, letting it slip into tablets or fragrance bases. Recent years bring interest from the fuel industry: as gasoline prices swing wildly, n-butanol seeks a niche as a renewable drop-in biofuel, boasting better energy density and less engine corrosion than ethanol.
Bio-based n-butanol attracts wide attention as sustainability becomes a stronger driver in purchasing decisions. New microbial strains and fermentation processes promise higher yields and easier recovery, challenging the dominance of petrochemical routes. Catalysts and reaction engineering methods aim to cut down waste and energy use in hydroformylation, too. Basic researchers keep poking the boundaries, designing downstream chemicals and composites that take advantage of n-butanol’s structure. Life cycle analysis and green metrics filter into product trials, especially where large-volume buyers want to shrink their carbon footprints.
Low toxicity keeps n-butanol on the safer side among industrial solvents, but that doesn’t mean it’s harmless. Acute exposure leads to irritation, dizziness, and headaches, while swallowing high doses brings on nausea and confusion. Chronic exposure at high levels can affect the nervous system and cause liver or kidney changes over time. Animal studies help map out the risks and keep workplace standards up to date. The move toward greener solvents and tighter occupational controls stems as much from these risks as from growing regulation.
N-Butanol stands at a crossroads where chemistry, sustainability, and changing industrial trends intertwine. The push toward renewable feedstocks and cleaner production methods points to a future full of bio-based n-butanol, grown from corn or even cellulosic waste. Engine performance data already hints at expanded use in gasoline blends that sidestep the drawbacks of ethanol. High-value chemical derivatives may pop up as new catalysts make modifying n-butanol cheaper and more selective. As industrial buyers jockey for lower emissions and better safety, n-butanol’s adaptability ensures it keeps showing up in surprising places, all while playing a familiar supporting role in the background of modern manufacturing.
N-Butanol sounds like the kind of thing that should only live in a science lab. The truth is, it’s part of plenty of things that show up in real life, sometimes in surprising places. I remember the first time I saw it listed on the side of a container in a hardware store—some long, mysterious name among all the other ingredients. Later, I learned it plays a big role beyond chemistry class.
Lots of folks use N-Butanol as a solvent. Industries turn to it when they want to mix, dissolve, or thin things out. Paint manufacturers, for instance, add it to make their products flow more smoothly. Try painting a room without a good solvent and you’ll discover how difficult things can get. N-Butanol keeps everything consistent, helps paint stick, and slows down drying so the finish stays even. Adhesive makers count on it for nearly the same reasons. Without dependable solvents, glue can turn into a mess, drying in clumps or failing to hold at all.
It’s easy to overlook how often N-Butanol slips into products you find at home. Take a bottle of nail polish or cleaning fluid from under the sink; odds are good they rely on alcohols like this one. It helps blend the colors, lets the liquid coat the nail evenly, or leaves fewer streaks on a window. Once you start to recognize these connections, you realize just how much everyday life leans on raw materials that seem to belong only in factories.
People talk a lot about the future of fuel. N-Butanol’s been floated as a possible biofuel, and researchers say it has higher energy content than ethanol. Plus, it doesn’t absorb water easily and doesn’t corrode engines the way other alcohols sometimes do. Some companies push for more investment in N-Butanol as an additive or separate fuel source, hoping to ease up on fossil fuel demand and lower pollution. Change comes slow, of course, since producing enough at a reasonable price takes serious innovation.
N-Butanol also pops up in fragrances and flavors, though no one wants to taste or smell it directly. Instead, manufacturers treat it as a starting point for making esters—flavor and scent compounds behind fruity notes in candies or perfumes. The irony is strong: a chemical known for its harshness, transformed into something sweet through careful processing. That kind of turnaround is one of those chemistry tricks you appreciate after spending any time reading ingredient lists or watching industry videos.
Every tool has a danger side. N-Butanol vapor can cause dizziness, headaches, eye irritation. Folks who work around it every day know to keep rooms well-ventilated and wear gloves. Here’s where public safety comes in. Far too many people skip the safety sheets, rush into handling it, and find themselves with a reaction or spill. Small manufacturers deserve better guidance or simpler rules on storage—clear labeling and regular safety checks would keep accidents down. If it ends up in water or soil through careless dumping, local wildlife pays the price. Industry leaders talk about training, but on-site inspections and outreach help even more.
I once thought “industrial chemicals” meant something far removed from real life, but N-Butanol ends up inside paint cans, solvents, and perfumes all around town. By paying more attention to how such chemicals get used—and misused—everyone can push for smarter policies and safer solutions. Science and industry still have work to do on cleaner production, waste reduction, and reliable protective gear. The rest of us can start by reading labels and asking where things come from, not just where they go in the end.
N-Butanol shows up in plenty of workplaces—paints, coatings, even just stored as a chemical building block. It doesn’t look too threatening at first blush. Colorless, a bit sweet-smelling, and it tends to blend in with other lab bottles. That’s probably why people sometimes drop their guard. Over the years, I've seen a few new lab workers treat it just like water. Before you know it, they’re not wearing gloves, or they forget about ventilation. That's a quick road to headaches, skin rashes, or worse.
Getting right down to it: N-Butanol won’t explode if you glance at it. But it is flammable, and the fumes can mess with your head if you spend a day around them without decent airflow. I remember a time in an older warehouse, folks used to prop open doors to “get some fresh air.” That trick doesn’t work when fumes are denser than air; N-Butanol vapor tends to hang low, lingering at floor level where you don’t even realize you’re breathing it. One slip with an electrical spark or a carelessly tossed rag, and suddenly things can go sideways.
Here’s the bread and butter of staying safe around N-Butanol, passed down from trainers who saw the aftermath of mistakes more than once:
I’ve had coworkers brush off skin contact—“It just tingled, no big deal.” That’s just not true. N-Butanol seeps in faster than you’d think, and repeated exposure leaves your hands cracking or red. Fumes can sneak up, too. Headaches, dizziness, and drowsiness look a lot like being tired, so folks keep working until they end up confused or even faint. One time I barely caught it—a labmate was about to drive after working an extended shift. She thought she “needed a coffee,” but she was clearly disoriented from the fumes.
Label everything—bold print, no abbreviations. Store the stuff in locked cabinets, away from direct heat or open flames. Leftover rags or clothing soaked in N-Butanol? Into sealed containers right away, not left on a bench. Training workers, not just once but every season, gives people a chance to refresh their habits. Sometimes just hearing a close call wakes everyone up.
Stronger habits start with a clear-eyed look at the risks: ventilation, gloves that actually work, and keeping stuff labeled and locked tight. Regular walk-throughs—just like those no-nonsense old-timers used to do—can spot problems before they snowball. N-Butanol rewards the careful and punishes the rushed. If more places encouraged simple, day-to-day vigilance—not just the fancy posters—fewer people would end up telling cautionary tales.
Grab a bottle of n-butanol and a glass of water, and you might expect a seamless mix like you’d see with sugar or salt. N-butanol doesn’t dissolve like that, and it has its own quirks. Stirring n-butanol into water gives a cloudy swirl, not total transparency. The stuff partially mixes, but doesn’t quite vanish.
Back in college labs, I watched classmates argue over what “soluble” even means. Some would pour a little n-butanol, swirl, and claim it was mixing fine. Others saw the layers forming and shook their heads. The technical threshold is about seven parts n-butanol will break into a hundred parts of water before separation starts showing up. Most solvents like ethanol disappear happily in water, thanks to their entire molecule loving the company of water molecules. N-butanol, though, sports a longer hydrocarbon tail, so only part of the molecule wants to make friends with water.
This isn’t just lab trivia or material for chemistry exams. Industries dealing with solvents—paint makers, cleaners, even the folks who brew up next-gen fuels—need to know how stuff like n-butanol behaves. Slightly soluble means n-butanol can form two layers if you use enough of it, and it can slip out of solution if conditions change. This unpredictability gets in the way for anyone trying to use it as a carrier for other chemicals, or blend it cleanly into water-based systems.
In wastewater treatment, for example, chemists chase after dissolved organics that don’t want to play by the rules. N-butanol is harder to snag out of water than some bigger hydrocarbons, but doesn’t vanish as easily as alcohols with shorter chains. That means more time, energy, or chemicals needed to clean up. From the safety side, those working in labs or factories have to pay attention. Waste down the sink? Trace solubility could mean low-level contamination and headaches for environmental teams, since it takes only a little to affect aquatic life.
Blowing off partial solubility gives us headaches later. I’ve seen workers trust the clear appearance of a mix and skip safe handling steps, believing it’s “just water” at that point. Trouble follows. My hands-on experience tells me there’s always a stubborn residue, a smell that lingers, or an unexpected reaction with other materials. This calls for more than a quick Google: chemists and users both benefit from better fact-checking, reading up on Material Safety Data Sheets, and using simple tools like test tubes or beakers to check mixtures before scaling things up.
Instead of fighting the stuff that won’t dissolve easily, some industries switch to other alcohols or even find ways to tweak their formulas. Adding a little surfactant—the kind that breaks up grease in dish soap—brings n-butanol and water together more smoothly, avoiding that oily layer on top. Trial and error has limits though, and it pays off to know what’s going on at the molecular level.
N-butanol’s love-hate relationship with water keeps chemists humble. Whenever something doesn’t dissolve all the way, it invites us to ask questions and change our approach. Solubility shapes how industries handle, clean up, and mix their products. Solutions start with noticing these stubborn leftovers and not assuming every chemical behaves like its cousins. I’ve cleaned up more failed mixtures than I care to admit, but those blunders taught me to respect even a half-dissolved drop in a beaker.
N-Butanol carries a reputation for being useful in a lot of manufacturing jobs, from paint and coatings to some plasticizers and even as a fuel or solvent. Once you peel back those uses, though, it’s clear N-Butanol isn’t exactly a “plug and play” chemical for any storage site. People often miss how much effort goes into keeping it safely shelved and ready for use.
From what I’ve seen in plant operations, the key driver for setting up N-Butanol storage starts with one simple fact: this stuff is both flammable and can give off vapors that get dangerous if not well managed. So, folks want to store it in places that won’t crank up the risk for fire or leaks.
Steel tanks, especially those lined against corrosion, show up over and over as a common choice. A plant manager once walked me around their yard, proud of how they still kept everything within fire codes. Tanks were kept apart, every vent piped away from walkways, and the secondary containment dikes sat ready for any accidental leaks. Setting these physical barriers up—concrete ditches, sealed surfaces—can sound like extra cost, but it buys peace of mind.
Fire safety is always top of mind for anyone storing something flammable. I’ve walked past enough safety signs to know N-Butanol storage gets treated with the same caution as lighter fuels. Sprinkler lines stay charged year-round, no matter the weather, and workers get regular briefings to remind them how fast vapors might catch if a spark flies.
The volatility of N-Butanol creates another problem. Storage rooms can’t just be standard spaces. Heat makes vapors build up faster, and it doesn’t take much imagination to picture disaster if someone ignores a hot storage corner for too long. Insulation around tanks, regular checks on cooling units, and steady air exchanges through strong ventilation all line up as tools kept in the playbook for limiting risk.
On-site at one manufacturer, they scheduled those tank checks as part of daily routines. Staff moved through, noting tank temperatures and vapor readings, aware that missing a single day could set the stage for something nobody wanted. Simple steps—hydrometers dipped in every tank, gaskets replaced after the faintest hint of aging rubber—helped prevent headaches later on.
It’s tough to ignore that federal and local laws drive much of the storage plan for N-Butanol. OSHA and EPA set the bar, and fines for ignoring them can put a big dent in any year’s profits. There’s a rule of thumb in facilities management: treat every drop as a potential hazard and expect an inspector at the door any morning.
Training workers forms a main line of defense, not just to tick a compliance box but to help people spot odd smells or slick spots before they get serious. Thorough record keeping, daily logs, and equipment checklists sometimes feel tedious, but in practice, those records have headed off big losses, especially after storms or power failures that might shake up a storage yard.
Looking ahead, automation and sensors cut the chance of human error. Some companies now rely on alarms and remote controls to shut lines or start scrubbing fans. This shift marks progress, but no hardware can swap out the value of trained eyes. At the end of the day, safe storage of N-Butanol circles back to constant vigilance, solid training, and choosing every tank and tool with future risks in mind.
Plenty of folks working in labs or running industrial equipment cross paths with N-butanol. It’s a liquid that tends to show up in places where people want a solvent that doesn’t evaporate off in a blink. With a chemical formula of C4H9OH, this stuff owes much to its sturdy four-carbon backbone. You notice its smell pretty fast—strong and a little sweet, like someone spilled vodka and forgot to mop up. Digging into its makeup tells us why it earned a regular spot in the chemical toolkit.
N-butanol spills across a bench much like water, but its best tricks show up when you raise the heat. It boils at about 117 degrees Celsius (243 Fahrenheit). If you handle it on a chilly morning, you’ll see it hang tight as a liquid down to about -89 degrees Celsius (-128 Fahrenheit). That means outdoor workers up north or people mixing chemicals in poorly heated warehouses aren’t likely to find chunks of frozen n-butanol ruining their mixtures.
N-butanol has a density around 0.81 grams per cubic centimeter, which means it floats on top of water. This trait gets noticed in actual spill cleanups or mixing jobs—anyone who’s ever tried to rinse it down the drain quickly learns it’ll layer instead of blending in smoothly. Folks using water-based products often mention this quirk: mixing takes real elbow grease.
Most experienced chemists can tell you right away: n-butanol mixes with water, but not with full enthusiasm. Try to stir it in, and you see some mixing at first, but keep adding water or alcohol and you find the limit sooner than you expected. Sometimes you see the two layers part ways, almost like oil and vinegar settling in salad dressing. This comes from its chain of carbons making part of the molecule too stubborn to harmonize with water’s love for hydrogen bonds.
Pick up a bottle—n-butanol feels oily, a far cry from water’s clean slip or ethanol’s breezy swish. Anyone who’s worked with it can tell you: try not to get any on bare skin, since it dries you out and leaves behind a stubborn smell. Accidentally spill some, and you’ll notice the stench holding tight, impossible to ignore for at least a few hours. Its vapor isn't just a sensory issue. Breathing it in, even by mistake, feels rough on your lungs. Users learn pretty quickly to crack a window or wear a mask instead of powering through the fumes.
The reasons industries prize n-butanol grow from its gritty properties. Painters need slow evaporating agents, labs need solvents that help coax out just the right reaction. Because of its boiling point and moderate water solubility, it slips into roles where neither fast-drying acetone nor heavy, sticky oils can do the job. Manufacturers making plastics, coatings, or specialty chemicals rely on n-butanol’s knack for balancing volatility and solubility.
People around paints, adhesives, or cleaning solutions meet n-butanol as a tool and a hazard. More than one story gets told about leftover open containers causing headaches, literal and figurative. The solution doesn’t come from fancier gear or stricter limits alone—a smart workplace puts value on strong training and clearly marked safety rules. Gloves, goggles, and good ventilation aren’t just for show. When real people understand what n-butanol can do and how it behaves, the risks start to shrink.
| Names | |
| Preferred IUPAC name | butan-1-ol |
| Other names |
1-Butanol n-Butyl alcohol Butan-1-ol Butyl alcohol Propylcarbinol |
| Pronunciation | /ɛnˈbjuː.tə.nɒl/ |
| Identifiers | |
| CAS Number | 71-36-3 |
| Beilstein Reference | 1361118 |
| ChEBI | CHEBI:28885 |
| ChEMBL | CHEMBL43092 |
| ChemSpider | 7438 |
| DrugBank | DB02166 |
| ECHA InfoCard | ECHA InfoCard: 100.004.438 |
| EC Number | 200-751-6 |
| Gmelin Reference | 878 |
| KEGG | C00474 |
| MeSH | D017176 |
| PubChem CID | 263 |
| RTECS number | EO1400000 |
| UNII | 3K9958V90M |
| UN number | UN1120 |
| Properties | |
| Chemical formula | C4H10O |
| Molar mass | 74.12 g/mol |
| Appearance | Clear, colorless liquid with a characteristic alcoholic odor. |
| Odor | Characteristic, banana-like |
| Density | 0.8098 g/cm³ |
| Solubility in water | 73 g/L (20 °C) |
| log P | 0.88 |
| Vapor pressure | 0.56 kPa (at 20 °C) |
| Acidity (pKa) | 16.0 |
| Basicity (pKb) | pKb ≈ 5.84 |
| Magnetic susceptibility (χ) | -54.6×10⁻⁶ cm³/mol |
| Refractive index (nD) | 1.3993 |
| Viscosity | 2.95 mPa·s (at 20 °C) |
| Dipole moment | 1.66 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 282.7 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -327.6 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -2674 kJ/mol |
| Pharmacology | |
| ATC code | C07AB56 |
| Hazards | |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS02,GHS07 |
| Signal word | Warning |
| Hazard statements | H226, H302, H315, H318, H335, H336 |
| Precautionary statements | P210, P233, P240, P241, P242, P243, P261, P264, P271, P280, P303+P361+P353, P304+P340, P305+P351+P338, P312, P337+P313, P370+P378, P403+P235, P405, P501 |
| NFPA 704 (fire diamond) | 2-3-0 |
| Flash point | 35°C |
| Autoignition temperature | 343°C (649°F) |
| Explosive limits | 1.4% - 11.2% |
| Lethal dose or concentration | LD50 oral rat 790 mg/kg |
| LD50 (median dose) | LD50: 2290 mg/kg (rat, oral) |
| NIOSH | PB8925000 |
| PEL (Permissible) | PEL (Permissible Exposure Limit) of N-Butanol: 100 ppm |
| REL (Recommended) | 100 |
| IDLH (Immediate danger) | 1400 ppm |
| Related compounds | |
| Related compounds |
Methanol Ethanol Propanol Isobutanol tert-Butanol |
