Butanesulfonic acid traces its roots back to the pioneering days of sulfonic acid chemistry in the early 20th century. Chemists kept seeking ways to add sulfonate groups to carbon chains looking to improve the solubility and reactivity of organic molecules. Butane itself, a simple four-carbon molecule rescued from the shadows of propane and pentane, gave researchers a fresh platform. Once the process of sulfonation matured, butanesulfonic acid found its mark because of its manageable size and reliable acid strength. Over decades, demand for strong, non-volatile acids in both laboratories and industry nudged butanesulfonic acid into a regular spot on chemical shelves.
What sets butanesulfonic acid apart boils down to how it serves as a strong acid with a straightforward structure. Its formula is C4H10SO3, usually delivered as a viscous liquid or occasionally as a white crystalline solid. Some suppliers offer it by the liter, targeting researchers who need both strong acidity and compatibility with organic solvents. The packaging usually reflects its robust, slightly oily texture, with tamper-evident seals and corrosion-proof bottles standing up to long-term storage.
Butanesulfonic acid brings a clarity to acid chemistry that a lot of its larger cousins can’t manage. With a melting point around 65-70°C and boiling at about 240°C (decomposing before boiling), it holds up under a lot of the usual heating that comes with organic syntheses. Its density falls near 1.18 g/cm³, and the substance flows easily unless cooled in the freezer. Acidity sits in line with other alkylsulfonic acids, landing a pKa close to -1, packing more acidity than most mineral acids used in the lab. Water, alcohols, and a fine selection of polar organic solvents handle butanesulfonic acid just fine, no struggle to stay dissolved or blended.
Labels on commercially available butanesulfonic acid tell a story of precision and control. Purity usually runs from 98% up to ultra-high purity, targeting even trace contaminants like iron or other heavy metals. You tend to see batch numbers, manufacturing dates, and lot tracking printed in bold font. Standardized hazard pictograms capture its corrosive edge, warning that skin, eyes, and lungs all face the same risk on unguarded contact. Lot-to-lot consistency means chemists rely on reproducible results, and traceability widens confidence in regulatory or pharmaceutical applications.
Manufacturers favor sulfonation of n-butane or butanol, using strong sulfonating agents like fuming sulfuric acid. Direct sulfonation of butane calls for careful temperature and pressure control, as the reaction borders on volatile. Some shops opt for indirect methods—taking butanol through oxidation first, then attaching the sulfonic group. Yields are respectable, with no major byproducts if watchful chemists keep oxidants and acids in check. This attention to detail cuts down on costly purification steps after production. Even though greener methods keep climbing the research agenda, the classic sulfuric acid dance still dominates industrial output.
Chemists lean on butanesulfonic acid for both its acid power and sulfonate functionality. It opens doors in esterification, often swapping its sulfonic group for other active agents to build up bigger molecules. Nobody overlooks its role as a leaving group in alkylation or substitution reactions. The broad compatibility means that researchers keep finding new tricks by pairing it with different reagents—making surfactants, catalyzing organic transformations, and even helping out as a counterion for drug development. Modifications extend to its sodium or potassium salt forms, which offer gentler handling and less aggressive acidity for more sensitive syntheses.
Butanesulfonic acid answers to a handful of aliases across chemical catalogs. N-butanesulfonic acid, butylsulfonic acid, and 1-butanesulfonic acid top the list. Older labels may reference its structure by IUPAC name or call out trade designations tailored for pharmaceutical or specialty chemical markets. Some vendors highlight the acid’s use in chromatography or as an ionic modifier, creating a bit of a branding jungle that slows down anyone not double-checking the CAS number (590-10-3).
From experience, one underestimates butanesulfonic acid’s bite at their own risk. It chews through gloves made from the wrong material—nitrile or neoprene hold up best. Fume hoods become indispensable, as vapors can irritate airways and eyes. Burn risks stay front and center, and washing spills with water can spread damage if not controlled. Chemical hygiene plans list it with strong acids, so training staff and keeping neutralization agents handy simplifies accident response. Storage spaces need ventilation and resistant shelving, especially once containers have been opened and resealed multiple times. Local and international regulatory bodies demand full hazard documentation on each shipment, pushing for a higher bar on transparency every year.
In the real world, butanesulfonic acid goes beyond benchtop titrations. Pharmaceutical researchers include it as a counterion to stabilize active drug ingredients, which can mean the difference between a stubborn powder and an easy-to-dose tablet. Electroplating shops pick it for acid baths where a strong, non-oxidizing acid rules out rusty outcomes. Chemical manufacturers turn to its sulfonate handle for making advanced surfactants, lubricants, and specialty additives that show up in paints, inks, or cleaning agents. Its place in ion chromatography labs as a mobile phase additive keeps chromatographers coming back—offering sharper peaks and better separation for small molecules.
For years, R&D teams have prodded butanesulfonic acid for fresh uses in greener chemistry and more selective synthesis. Companies invest in process optimization to scale-up production with less waste and lower energy. At the molecular level, researchers keep tinkering with modified versions—slapping functional groups next to the sulfonate to create bespoke acid catalysts. New projects examine how its acid strength and streamlined chain can help build polymeric materials or ionic liquids with tuned behavior. There’s an appetite for biocatalytic or electrochemical preparation methods, aiming to slash hazardous by-products and make waste treatment easier.
Toxicity studies on butanesulfonic acid reinforce its status as a chemical needing respect. Skin and eye irritation rank high if workers skip protection. Inhalation trials show dose-dependent effects—coughing, sneezing, and respiratory distress—in animal models and rare workplace incidents. Most reports say it doesn’t hang around in the environment like heavier sulfonic acids, breaking down into sulfate and simple organics within a few weeks after disposal. Chronic exposure data stay relatively sparse, nudging companies to keep airborne and surface levels below published thresholds. The push for more complete data has drawn attention from academic research teams and public health agencies alike.
Looking ahead, butanesulfonic acid stands ready for more than just routine acid-catalyzed reactions. It offers a foundation for next-generation catalysts, especially in sustainable chemistry and renewable materials. Interest grows in its role for advanced battery electrolytes—especially as the world doubles down on grid storage and electric vehicles. Ongoing refinement of its synthesis—shifting from bulk chemicals to more efficient, lower-emission factories—promises both a cleaner footprint and better pricing. As regulatory landscapes turn stricter and industries crave higher performance with lower hazards, development teams keep butanesulfonic acid on speed dial, eager to unlock whatever applications appear next.
Anyone who has worked in a chemistry lab knows there’s a bench crowded with glassware, bottles, and a few chemicals that only the staff chemist seems to understand. Butanesulfonic acid often sits among those bottles, but this isn’t one of those “mystery chemicals” for long. In my early bench chemistry days, I learned quickly how this unassuming acid gets put to use where a strong touch is needed without the splash of old standbys like sulfuric acid.
Electroplating folks—whether at big factories or in tiny jewelry shops—sometimes rely on butanesulfonic acid in their electrolyte solutions. This acid brings a level of stability and conductivity some other acids can’t match. You get smoother surfaces on finished products, meaning fewer blemishes and a better sale value. I once toured a plating facility that switched over to butanesulfonic acid for their copper baths; their scrap rates dropped and their workers appreciated the gentler smell compared to older plating acids.
For chemists making medicines, flavors, or dyes, butanesulfonic acid stands out. It acts as a catalyst and helps steer chemical reactions toward the right target. In the pharmaceutical world, reliable results matter. Butanesulfonic acid's predictable behavior and water solubility let researchers and manufacturing teams avoid messy by-products. The cleaner the reaction, the less time and money spent purifying what you end up with.
Anyone who’s filtered through a stack of sample tubes in an HPLC lab will recognize the name butanesulfonic acid. It gets added to mobile phases in chromatography to sharpen up separation between similar molecules, especially basic drugs or peptides. My time in analytical chemistry showed me how a tweak in the buffer—using butanesulfonic in place of the usual acids—often helped untangle peaks that seemed glued together on the chromatograph.
More people interact with butanesulfonic acid than they might think. Some surfactants—the key players in liquid soaps, shampoos, and cleaners—spring from sulfonic acids like this one. Oilfield companies, for example, use its derivatives to help pull up more crude oil from the ground by altering the way water interacts with trapped petroleum. Cleaners built with these surfactants prove their worth in every greasy mechanic’s shop or restaurant kitchen.
Like many strong acids, butanesulfonic acid can burn skin and require goggles and gloves. The difference lies in how much more friendly it seems when stored and used right. I’ve seen plant safety officers lay out detailed protocols—spill kits, neutralizers, and clear instruction labels. This isn’t just about regulation but about daily respect for chemicals that make modern manufacturing work.
Green chemistry research keeps pushing for acids and catalysts with less impact on people and the earth. Some labs now explore renewable sources to make butanesulfonic acid, aiming to shrink its footprint from start to finish. I believe the next five years will see more companies demanding traceability and greener processes, nudged forward by new regulations and customers asking tougher questions. As more industries want clear answers about where their chemicals come from, the full story of butanesulfonic acid will only grow.
Butanesulfonic acid might seem obscure in daily conversation, but its impact stretches from labs to industrial kitchens and even into the grocery aisle. The formula for this compound is C4H10O3S. That’s four carbons, ten hydrogens, three oxygens, and a single sulfur atom working together. Named for its backbone – butane, a straightforward four-carbon chain – butanesulfonic acid stands out because it swaps a classic methyl or ethyl group for a sulfonic acid group (–SO3H).
What makes this matter? That sulfonic group doesn’t just sit idle. Sulfonic acids turn up as key players whenever serious acidity is needed, but you don’t want the volatility of a strong mineral acid like sulfuric. Compared to more dangerous materials, butanesulfonic acid brings strong acid behavior with a manageable vapor pressure. So, in environments like chemical synthesis, its formula directs its role as either a catalyst or as a mobile-phase additive in chromatography.
Looking back on my own experience in a makeshift home lab, making solutions sometimes turns stressful with stronger acids, but a manageable organic acid like butanesulfonic feels far more forgiving. With fewer hazardous fumes than hydrochloric or sulfuric acid, spillage doesn’t strike the same panic. Chemists often reach for this one where reactivity and relative safety need balancing.
C4H10O3S seems like just a string of letters and numbers, yet in areas like pharmaceuticals, tiny shifts in a molecule make or break a process. As an ion-pairing agent, butanesulfonic acid changes how drugs dissolve and behave in liquid chromatography. Accuracy matters: use a different chain length or shuffle atoms and suddenly the compound falls short in selectivity or solubility.
In food processing, regulations demand precision, not close guesses. The wrong compound or impure formulation around food can result in unwanted reactions or introduce contaminants. Chemists rely on strict formulas to meet legislation and health standards. The detailed structure of C4H10O3S keeps production and research running smoothly.
Mix up the formula or use a similar-sounding acid, and downstream effects range from product recalls to dangerous reactions. Sulfonic acids look and sound alike, but branching, position, and purity make a difference. My first encounter with sulfonic acids left me triple-checking chemical labels, especially after witnessing a colleague grab the wrong beaker – a safety lesson nobody forgets.
Simple questions about chemical formulas open up a whole world where knowledge and detail shape safety, results, and trust. Keeping chemical identities precise and transparent builds a bedrock for chemistry’s practical applications. Tackling confusion with direct education and thorough labeling not only protects end users but also serves up better results across science, medicine, and industry.
Butanesulfonic acid shows up in the world of chemistry as a heavy lifter. The stuff doesn’t get flashy headlines, but for labs and factories, it acts as a strong acid and a trusty additive. Plenty of folks outside research labs rarely think about it, so it’s fair to ask: how dangerous is this chemical? Should workers or neighbors worry? And what should companies keep in mind before bringing it into their processes?
A chemical’s name alone doesn’t lay out its entire risk profile. Talking to chemists, I’ve learned that butanesulfonic acid, like many sulfonic acids, stings. Direct contact with the skin or eyes usually burns and irritates. You don’t want to inhale the vapors, as they start to mess with mucous membranes—think coughing, trouble breathing, and a burning nose and throat. The risks spike if you ignore gloves, goggles, or fume hoods. A quick spill on a lab bench, washed up the right way, probably won’t cause lasting harm to most healthy people. But a careless splash in an eye, or a routine of bare-handed work, might leave permanent damage.
I’ve watched seasoned lab techs treat butanesulfonic acid as “cautious but routine.” That attitude tells you a lot. It’s not a compound where a drop means emergency showers or panic, but it’s also not something to treat like dish soap. Handling gets safer with habits: online safety data sheets (SDS) say to use gloves, goggles, long sleeves, and local ventilation or fume hoods. Washing up after working with strong acids remains a simple, important act any time—soap and water still rank as the first line of defense.
Some chemicals linger in soil, harm aquatic life, and travel through air or water. Butanesulfonic acid, with enough of it spilled, can acidify water or soil. This means plants, fish, or insects in the area may get hurt. Environmental agencies ask companies to store and dispose of the acid in drums, not pipes or drains. Spills need neutralizing—often with something like lime or soda ash—so the acid can’t stand a chance at traveling onward as a hazard. I’ve known factory safety managers who run regular training to be sure this step isn’t skipped, since even small leaks could throw off wastewater treatment equipment or nearby streams.
The acid doesn’t show up on lists of “most toxic” industrial chemicals. Cases of life-threatening exposure stay rare and usually connect to people ignoring safety advice. No data shows the acid causes cancer. Animal testing points at irritation and burns, not slow, sneaky poisoning. With good ventilation, skin protection, and sticking to safety protocols, handling butanesulfonic acid lines up with many other acids. The bigger dangers don’t come from the substance’s chemical structure—they come from neglecting basic safety steps.
Careful handling and thoughtful storage make a huge difference, even before digging into high-cost safety technology. Labeling bottles clearly, keeping acids locked away, and training staff on simple emergency procedures go a long way. I’ve seen workplaces cut chemical accidents just by running live demonstrations—spilling a few drops of acid on worn gloves, watching the fizz, and hammering in the reasons for the rules. Setting up a workplace where nobody needs to rush and everyone has the gear ready creates a culture that respects both the risks and the people facing them. Clean habits, good gear, and honest communication about safety do more to prevent harm than any chemical reformulation ever could.
Butanesulfonic acid doesn’t make headlines until something goes wrong. Anyone who has spilled even a drop in a lab knows its sting. Handling a compound like this means paying close attention not just to safety data sheets, but also to the real life habits that protect people and property. Storage isn’t a checklist item—it’s an everyday responsibility rooted in real consequences and common sense.
Most people in chemistry see butanesulfonic acid as a strong acid with corrosive qualities. That means it can burn skin, eat through metal, and ruin equipment. Fumes can get into the air and make breathing tough. It reacts with water in ways that might surprise someone used to working with less aggressive chemicals. I remember the first time I watched a careless splash; the cloud that rose up was enough to teach everyone in the lab a lesson.
Plastic wins here—high-density polyethylene stands up against the acid without corroding or leaking. Metal doesn’t last; glass can crack if you’re unlucky or if the acid gets too warm. I’ve seen old, flimsy jugs bow out and start to drip, making a mess no one wanted to clean up. Skip the temptation to reuse any random bottle. Labels should be clear and visible, not scrawled on with a marker after the original’s washed away.
It’s tempting to leave containers near benches and sinks for quick access. I’ve made that mistake before, only to regret it when an elbow sent a jug tumbling. A good storage spot means a cool, dry shelf—never the floor, where spills go unnoticed or someone might trip. Keep it away from sunlight and heat sources, which can change the pressure inside the bottle. Flammable chemicals, bases, and oxidizers shouldn’t share the same cabinet. Those combinations lead to reactions no one wants to clean up, and certainly not to explain later in an incident report.
Even with lids screwed on tight, fumes can leak. I’ve seen storerooms thick with the smell of acid. Good airflow cuts down the risk of inhaling those vapors. Open windows aren’t always enough. A proper chemical storage cabinet fitted with vents makes a real difference, especially if you’re sharing the space or using it often. Respirators work, but nothing beats prevention.
Personal experience shows that labeling goes beyond the basics. Include dates, hazards, and the name of whoever last opened it. Adding a spill kit right next to storage means no searching if something happens. Training everyone in the same habits stops accidents before they start. Faculty and industry guidelines often give good starting points, but they can’t replace a routine that looks after the whole team.
Safe storage builds trust in a workspace. Clear rules and practical steps beat good intentions every time. Tending to the basics—not rushing, labeling, choosing the right spot—saves thousands in equipment costs and keeps people healthy. Working with strong acids like butanesulfonic calls for respect and a willingness to ask questions. Stay curious about safety, and most problems get solved before they ever become emergencies.
Butanesulfonic acid, a clear liquid or sometimes a colorless crystalline solid, stands out because of its striking stability and its role in both lab and industrial chemistry. I still remember the first time I handled a bottle of butanesulfonic acid in my university lab—the sharp smell lingered, and the liquid’s clarity belied its strength. Right off the bat, its most obvious trait is its strong acidity. This compound doesn’t mess around; it can turn a solution acidic fast, thanks to the sulfonic acid group attached to a straightforward butane backbone.
Temperature changes the way butanesulfonic acid presents itself. At room temperature, you’ll usually see it as a colorless liquid, but you may find it solidified if the thermometer drops below about 15°C. Its melting point hovers just below room temperature, and its boiling point goes well above the threshold for water. This wide temperature range means that it stores and ships without drama, but any accidental exposure to heat can quickly send fumes into the air if bottles aren’t sealed tightly.
Most lab chemicals play it safe with water or ethanol, but butanesulfonic acid takes to them like a duck to water. It mixes completely with both, no layers or settling. Thanks to its high polarity, it breaks down in water and forms a strong acidic medium, making it valuable for reactions where you want both powerful acidity and a stable solution. In one organic synthesis I ran, the acid’s homogeneity meant faster, more reliable reactions than older, more finicky acids allowed.
On the scale, butanesulfonic acid is heavier than water. Its density lands around 1.2 grams per cubic centimeter. In the bottle, this heft feels real; you can tilt a flask and watch it pour a bit slower than, say, simple alcohols. This weight influences how it gets handled in industrial equipment—pumps and valves call for materials that resist both corrosion and unexpected pressure spikes from denser fluids.
Anyone opening a capped container of this acid will notice a strong odor, almost suffocating if you get too close. Unlike some acids that can hide in plain sight, butanesulfonic acid warns users with its pungency. The color stays clear or white, and the liquid texture signals purity—as soon as contamination creeps in, cloudiness usually follows, so quality control techs learn to watch for any change in appearance.
Spilling a few drops burns skin and damages most metals. Gloves and goggles should never gather dust when this acid appears on the bench. From experience, one slip can mean ruined shoes or, worse, a bad skin rash. Labs and factories invest in stainless steel or polymer-lined storage to ward off breakdown. Local exhaust fans clear away the sharp vapors that can irritate lungs and eyes. Training for chemical handling never goes out of style—every new intern has to respect the bite that butanesulfonic acid brings.
Keeping track of physical traits—boiling point, melting point, density, solubility—goes beyond memorization. In production plants, these numbers guide safe handling and efficient reactions. Transportation teams read data sheets for details on storage temperatures and compatible containers. Chemists lean on these properties for troubleshooting stubborn syntheses, choosing substitutes, or scaling recipes. Everybody in the pipeline, from warehouse workers to researchers, depends on a clear understanding of what butanesulfonic acid can and will do in their hands.
| Names | |
| Preferred IUPAC name | Butane-1-sulfonic acid |
| Other names |
1-Butanesulfonic acid Butylsulfonic acid n-Butanesulfonic acid |
| Pronunciation | /ˌbjuː.teɪn.sʌlˈfɒn.ɪk ˈæs.ɪd/ |
| Identifiers | |
| CAS Number | 590-10-3 |
| Beilstein Reference | 1721394 |
| ChEBI | CHEBI:42560 |
| ChEMBL | CHEMBL152577 |
| ChemSpider | 59673 |
| DrugBank | DB14219 |
| ECHA InfoCard | ECHA InfoCard: 100.012.400 |
| EC Number | EC 214-956-6 |
| Gmelin Reference | 69113 |
| KEGG | C01698 |
| MeSH | D016426 |
| PubChem CID | 11244 |
| RTECS number | EO5950000 |
| UNII | 06K5D5G167 |
| UN number | UN1993 |
| CompTox Dashboard (EPA) | DTXSID2022729 |
| Properties | |
| Chemical formula | C4H10O3S |
| Molar mass | 150.21 g/mol |
| Appearance | White crystalline powder |
| Odor | Odorless |
| Density | 1.088 g/mL at 25 °C(lit.) |
| Solubility in water | Soluble in water |
| log P | -1.3 |
| Vapor pressure | 0.0125 mmHg (25°C) |
| Acidity (pKa) | -1.5 |
| Basicity (pKb) | -1.3 |
| Refractive index (nD) | 1.428 |
| Viscosity | 2.08 mPa·s (25 °C) |
| Dipole moment | 2.94 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 172.6 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | -577.1 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -2140 kJ·mol⁻¹ |
| Pharmacology | |
| ATC code | A16AX11 |
| Hazards | |
| GHS labelling | GHS02, GHS07 |
| Pictograms | GHS05,GHS07 |
| Signal word | Warning |
| Hazard statements | H314: Causes severe skin burns and eye damage. |
| Precautionary statements | P264, P280, P301+P312, P305+P351+P338, P330, P337+P313, P501 |
| Flash point | 70°C |
| Autoignition temperature | 340°C |
| Lethal dose or concentration | LD50 oral rat 5200 mg/kg |
| LD50 (median dose) | LD50 (median dose): Rat oral 5200 mg/kg |
| NIOSH | EW2975000 |
| PEL (Permissible) | Not established |
| REL (Recommended) | 0.5-1.0% |
| Related compounds | |
| Related compounds |
Methanesulfonic acid Ethanesulfonic acid Propanesulfonic acid Pentanesulfonic acid |
