知識について
Stannous Chloride Anhydrous: From Discovery to the Cutting Edge
Historical Development
Human curiosity with metals and their salts drummed up interest in tin compounds long before most folks gave periodic tables a second thought. By the time Carl Wilhelm Scheele began teasing apart tin reactions in the late 1700s, stannous chloride already saw its way into dye houses and glassmakers’ workshops across Europe. Early glassworkers relied on it to cut annoying green tints caused by iron impurities. Since then, its chemistry opened new doors in metal refining, pharmaceuticals, and countless industrial processes. Some of those old applications faded as we learned more about toxicity and safer alternatives grew, but stannous chloride’s ability to donate electrons keeps hands-on chemists and manufacturers returning again and again.
Product Overview
Stannous chloride anhydrous, also called tin(II) chloride, usually shows up on the shelf as a crystalline powder that dissolves fast in water and many polar solvents. Unlike the dehydrate form, the anhydrous type keeps water away, which matters in electronics, pharmaceuticals, and precision syntheses. Reagents this reactive often bridge science and industry. Old-school names include Tin Dichloride and E512 in the food context, although tighter regulations in food applications reflect growing caution about metals in the food chain.
Physical & Chemical Properties
Pop open a fresh container and out pours white granules, dense and glittery, telling you right away it’s not a bland salt. It packs a formula of SnCl₂ and clocks in at a molecular weight just shy of 190. In humid air, it chunks up fast, turning sticky and forming basic salts. Strong reducing power means it reacts with oxygen, acids, or even traces of moisture, making lab storage a balancing act. It scores a melting point around 247°C and decomposes in hot water—a headache in some syntheses, useful in others. Unlike many simple chlorides, it carries a faint sharp odor and eats through aluminum or zinc, marking out its use for growing specialty crystals.
Technical Specifications & Labeling
Suppliers print purity grades prominently, since tiny impurities quickly spoil batches in electronics or pharmaceuticals. You’ll see numbers like 98% or higher, pharma-grade, or sometimes technical and lab-grade listed. Labels warn against contact with water and air and usually ship the powder in sealed metal cans or glass bottles. Regulatory info includes its UN number (UN3260), warning pictograms, hazard statements about respiratory irritation, and the advice that medical help is in order after significant exposure. Industrial customers check for particle size, solubility, and stability details, since these play directly into yield and cost.
Preparation Method
The workhorse method starts by dissolving metallic tin scraps or ingots into hydrochloric acid, capturing the rising hydrogen in a fume hood. Larger plants work at low temperatures and use reflux to improve yield and prevent oxidation to Sn(IV) compounds; more careful labs bubble dry hydrogen chloride over pure tin, then sublime the product away from air. Some older processes used chlorinated solvents, but most serious manufacturers now avoid them. Keeping air out at every stage stays key, since the compound oxidizes if left in contact too long. Once finished, the crystals need quick drying and airtight packing, or they absorb water from the atmosphere and go lumpy.
Chemical Reactions & Modifications
Stannous chloride earns its keep by donating electrons—reducing precious metals like gold, silver, or platinum from solution, unpacking fabric dyes, or kicking off organic syntheses where a mild touch is needed. It reacts with acids by forming aqua complexes, and with strong bases spawns tin hydroxides. Exposing stannous chloride to halogens turns it straight into stannic chloride, and gentle heating with alkalis generates stannates. The ability to toggle between oxidation states, especially under careful temperature and pH control, lands it in analytical chemistry labs and custom synthesis shops. Blending with other tin salts or organic ligands opens up specialty catalysts or paint stabilizers, while in rare cases, it enters solid-state research in the hunt for new battery materials.
Synonyms & Product Names
Manufacturers, researchers, and regulators all give this compound its own twist. “SnCl₂” pops up in journals, “Tin(II) Chloride” in catalogs, “E512” in food settings, and “Riddell Solution” among art conservators. International shipping documents might use “Stannous Chloride Anhydrous,” “Dichlorotin,” or just “Tin salt.” On older European material safety documents, you’ll sometimes see “Chlorure d’Étain(II)” or “Cloruro di Stagno.” Such an array of names reflects a long history of use crossing national, industrial, and academic lines.
Safety & Operational Standards
Open up a drum in the wrong setting and a cloud of hydrochloric acid vapor or tin dust stirs up irritation fast—eyes, lungs, throat. Long-term exposure ups the risks around gastrointestinal distress, skin sensitization, and liver or kidney impacts, especially in poorly ventilated workshops. Modern safety training leans heavily on gloves, goggles, and local exhaust ventilation. Anyone running a pilot plant or a research lab knows stannous chloride stays locked up, never stored with oxidizers or moisture sources. Waste solutions require neutralization or professional disposal. Annual audits, environmental monitoring, and staff medical checks reinforce the message that tin’s versatility brings both promise and consequences.
Application Area
Few compounds jump across as many industries. In metallurgy, a splash of stannous chloride dips into precious metal recovery—recovering silver from photographic plates, stripping gold from e-waste, plating on jewelry and circuit boards. Electronics manufacturers lean on its mild reducing abilities to etch glass, produce fine copper powder, and prep surfaces for soldering. In textiles, traditional dyers once relied on it to brighten colors, though environmental rules curtailed this use. Dental materials and some pharmaceuticals include it in pastes and astringents, leveraging its antibacterial powers. Conservationists and art restorers value it for re-tinning old mirrors and preserving delicate artifacts. Some specialty chemical plants churn out flavor enhancers and antioxidants from it, though much of the food industry moved on to safer, less controversial alternatives.
Research & Development
Academic labs look for new ways to push stannous chloride’s limits. Organotin researchers pick apart how it kicks off reactions in low-pH or controlled-atmosphere settings. Its reducing capabilities spark curiosity in nanoparticle synthesis, where size, shape, and purities matter. Green chemistry projects explore modified routes to cut waste and energy—vapor-phase depositions, closed-loop acid recovery, and smarter recycling protocols. Recent patents highlight tailored stannous-based catalysts for plastics, solar cells, and even hydrogen evolution, all hinging on fine-tuned purity or modified surface states. Analytical chemists keep pushing detection limits of trace stannous in environmental or clinical samples using mass spec and electrochemistry, tying toxicological risk directly back to real-world exposure.
Toxicity Research
Toxicologists point out that, while tin(II) itself doesn’t rank with the worst industrial contaminants, chronic exposure or improper handling raises real issues. Animal studies show kidney and liver stress at higher doses; tin compounds can leach calcium and disrupt enzyme activity. Food scientists keep close tabs on migration from stannous salts into canned goods, recalling episodes where metal levels exceeded safe thresholds. Workers in plating or chemical industries see higher urinary tin, putting occupational guidelines in the spotlight. Environmental studies show slow breakdown under certain conditions, leading to potential accumulation in rivers and soils downstream from manufacturing sites. Monitoring programs check both industrial emissions and municipal water for trace stannous, reflecting a shift toward risk-based stewardship.
Future Prospects
Ongoing research turns up new possibilities in energy storage, electronic wafer fabrication, and sustainable metal recycling, all of which need fine control over purity and reactivity. Advances in process automation, real-time contaminant tracking, and closed-system synthesis promise cleaner, safer production. Lawmakers and NGOs press for even stricter limits on workplace and environmental tin exposure, nudging industries toward continuous improvement. Alternative reducing agents, green solvents, and engineered containment emerge as possible competitors or companion technologies, though none has replaced stannous chloride in all its niches. The challenge remains: balance proven chemistry with human and environmental health, setting the stage for next-generation materials and manufacturing.
What Makes Stannous Chloride Anhydrous Special?
Stannous chloride anhydrous, better known as tin(II) chloride, isn’t something you see on the grocery shelf, but it quietly powers a wide range of daily necessities. Its chemical formula is SnCl2, usually found as colorless crystals that dissolve easily in water. This may sound pretty dull, but the action happens once it gets into the hands of chemists, manufacturers, and technologists.
Heavy Lifting in Industry
This compound stands out in metal industries. Folks who electroplate metals—especially tin, silver, and gold—use it as a reducing agent. That job means it helps coat cheaper objects, like steel cans, with a layer of tin that resists rust and gives our food packaging a longer shelf life. Without tin plating, canned goods wouldn’t last nearly as long.
Lab technicians make use of stannous chloride in dye and pigment production. Textile and paint makers rely on its ability to help certain colors "take" better on fabric and surfaces. When I spent a summer in a dye house during college, every batch of specialty fabric we made got a dose of this compound to get deep reds and vivid purples. It may look like magic, but it’s straight chemistry.
Keeping Technology Running Smoothly
The electronics world relies on this compound, too. Manufacturers of printed circuit boards (PCBs)—the backbone holding together every gadget from smartphones to coffeemakers—use it as a starting point for applying metallic coatings. It plays a crucial role in creating connections that let electricity flow efficiently.
Healthcare and Pharmaceuticals
Stannous chloride has carved a niche for itself in healthcare. It’s a key ingredient in some radiopharmaceuticals, where it helps prepare imaging agents for diagnostic scans. Doctors rely on these agents to track how organs work and spot problems like cancer or heart disease. Without compounds like this, modern medical imaging would lose some of its precision and power.
Dentists have also tapped into its value. It often turns up in toothpaste under the name "stannous fluoride," stemming from a reaction where stannous chloride helps make stannous fluoride. This version fights gum disease and tooth sensitivity, a feature that’s helped millions of people keep their smiles healthy and pain-free.
Tough Challenges and Solutions
Working with stannous chloride anhydrous means handling some tough safety and environmental questions. Exposure to its dust can irritate the skin and lungs, and bigger spills can threaten water quality if not managed well. I remember fumbling with the stuff in a lab and learning that solid protocols—like sealed containers and proper ventilation—aren’t just for show. Every shop and lab relying on this chemical needs clear training and regular safety drills.
Factories are working on limiting runoff and recycling as much leftover tin as possible. Adding strong waste treatment steps cuts down the risk. Regulators have pushed for updates to these protocols in recent years, and many companies stepped up, adopting greener equipment and changing how chemicals get stored and transported.
Looking Ahead
As industries keep evolving, smart innovation will shrink the environmental footprint and make this compound even more useful. Training workers properly, updating equipment, and using new waste technology create a safer path forward. Day to day, stannous chloride anhydrous keeps proving its worth—quietly, but powerfully, in technology, healthcare, and industry.
Stability Takes Priority
Anyone who’s dealt with stannous chloride anhydrous knows it’s not your average lab salt. Once you crack open a fresh bottle, you understand why storage isn’t just a technicality. This white, highly water-reactive compound pulls moisture from the air almost like it’s hungry for it. Before you know it, that anhydrous “dry” powder clumps up, changes color, or picks up water to become its dihydrate form. It loses strength and can even be dangerous if handled without care.
Keeping Moisture Away
Based on my time preparing solutions and troubleshooting failed reactions, controlling humidity pays off. If you leave stannous chloride anhydrous on the bench overnight, you’re not just risking lab messes—you’re throwing away money as the chemical degrades.
Always store it in tightly sealed, airtight containers. Original packaging from reputable suppliers usually gets the job done, since it’s often lined with moisture barriers. Some stick with glass bottles equipped with screw caps and rubber liners. Forget using a simple snap-top plastic container; moisture finds its way in before you realize it.
Avoiding Heat and Sunlight
Direct sunlight isn’t a friend to stannous chloride either. Keep the storage location cool and out of rays, since heat speeds up decomposition. Industry guidelines recommend a storage temperature somewhere between 15 and 25°C—think about the conditions you’d want for medicines, not outside on a loading dock in July.
Chemical Compatibility Matters
This chemical reacts aggressively with oxidizing agents and acids. If you don’t separate storage spaces, you create a risk for fires or toxic gas leaks. From what I’ve seen, storing it in a designated cabinet—often one meant for chemicals sensitive to air and moisture—makes routine handling safer. Grouping it with other reactive materials increases the likelihood of accidents.
Monitoring for Contamination
Users sometimes overlook the little things, like opening a jar with gloves that have touched water or acids. Every exposure to the open air lets in tiny amounts of moisture, so only open containers right before use. Having some desiccant packs, like silica gel, inside the container keeps things drier. If the contents start looking clumpy or yellowish, it’s a sign things aren’t going well, and you should test efficacy before using it in important work.
Training and Labeling—Don’t Cut Corners
Science isn’t just about having the best gear or biggest lab. Knowing the ins and outs of practical safety makes all the difference. New staff benefit from hands-on demos, walking through safe transfer, labeling, and what a compromised stock solution looks like. Labels should always indicate the date opened, since older stocks can become unreliable. In regulated settings, documentation of checks and regular disposal of compromised material keeps labs safe and compliant.
Simple Solutions Make a Difference
Switching out faulty caps, updating signs, and replacing worn desiccants all help. Some teams even log container weights to spot moisture gain. In my experience, letting maintenance slip because things “look fine” leads to headaches down the line.
Why It All Matters
Respecting stannous chloride’s quirks—the need for dry, cool, separate, and secure storage—protects budgets, reputations, and people. Fail at this, and no lab insurance policy will undo the wasted time or risk of slipping a degraded chemical into a critical process.
Understanding the Substance
Stannous chloride anhydrous isn’t a household name, but it shows up in more familiar places than people might realize. Plating shops, pharmaceutical labs, and even dye production lines keep it on their shelves. At a glance, it’s a dry, white, crystalline powder. The story turns hazardous when you dig into its chemistry and how it reacts with its surroundings.
Why Hazards Matter Beyond the Safety Sheet
Many of us see chemical hazards as a problem for lab techs and factory workers. My time spent teaching high school science and working in municipal water treatment showed me this idea misses the bigger picture. Chemicals like stannous chloride touch lives in countless ways long before and after lab coats step in the door.
Without moisture, stannous chloride stays relatively stable. Expose it to air, and it starts drawing in water vapor, forming hydrochloric acid and other irritants. Even a whiff or loose skin contact can create a nasty surprise—coughing, burning, or a stubborn skin rash. In spaces without strong ventilation, fumes creep up, causing headaches or eye pain. Anyone who’s mixed acids in a closed closet knows this risk.
Real Risks in Everyday Handling
Burns and respiratory irritation are big concerns for workers. Stannous chloride can eat into skin and eyes, so even a small spill spells trouble. Problems pop up quickly in hot or damp conditions, as the heat and humidity encourage more reaction with water vapor. Someone pouring powder from a rusty tin can into a beaker isn’t just risking a mess. One misstep and hydrochloric acid vapor turns a regular work day into a dash to the eyewash station.
Aquatic toxicity doesn’t get much public attention, yet environmental health isn’t optional. Runoff from industries can dump tin byproducts into streams, hurting fish and even ending up in our drinking supplies. Taking shortcuts in disposal or storage might save a few seconds but causes heartbreak for entire communities downstream. Having witnessed a river near my childhood home turn slick with dead fish after a local shop's mess-up, this isn’t just a line on a warning label.
Worker Safety, Environmental Responsibility
Effective solutions start with respect for basic precautions. Gloves, respirators, lab coats, and face shields belong on anyone dealing with stannous chloride. Spills should never get casually swept up—using the right absorbents and containers stops bigger problems. Regular safety drills save more than fines; they keep workers from harm.
Doing the job right means thinking ahead about how chemicals might leave the building. Proper waste collection isn’t just busywork. Rinsing gloves and glassware down the drain moves the problem elsewhere. Local regulations aren’t about red tape—they build a buffer between mismanagement and disaster. Community groups are starting to track chemical dump sites after seeing how easy it is for one mistake to ripple out.
Trust, Transparency, and Prevention
Companies that publish clear safety data and train staff foster trust on the work floor and with the people living nearby. Transparency means more than paperwork; it makes workers feel seen and drives local support. By practicing genuine stewardship, workers and communities benefit from both safety and strong business.
Stannous chloride anhydrous is a useful tool, but it’s not benign. Respect, responsibility, and a bit of healthy caution let people and the environment thrive even in a world of complicated chemicals.
What Is the Chemical Formula?
Stannous chloride anhydrous holds the chemical formula SnCl2. In the world of chemistry, “stannous” points to tin in the +2 oxidation state. Here, one atom of tin bonds with two atoms of chlorine. Water molecules do not attach to this form, making it “anhydrous.” The presence of water makes a big difference in many chemical compounds, but pure anhydrous form delivers a direct, unhydrated composition.
Why Does SnCl2 Matter?
Over the years, I have seen labs and workshops treat stannous chloride like a toolbox staple. It jumps into action during processes such as electroplating, dye manufacture, and especially in tin-based chemical reactions. Plating requires materials that handle reduction reactions efficiently, and SnCl2 fills that role by turning ions into usable metal layers. The chemical does not just stick to industry — even schools bring it out for practical demonstrations about how metals behave and interact.
Stannous Chloride Anhydrous in Everyday Use
In my hands-on experience, using anhydrous over hydrous forms often helps avoid unwanted side effects. Water in chemicals can react or dilute, which changes results and sometimes spoils sensitive recipes. Anhydrous SnCl2 gives more control. For people passionate about conservation of historical artifacts or those running complex chemical syntheses, this compound’s predictability stands out.
Real Risks and Responsible Handling
Safety always stays in the spotlight. Direct contact may irritate skin and eyes, and the fumes can bother airways. Protective gloves and decent ventilation serve as a better approach than shortcuts or quick fixes. Nobody wants accidental burns or long-term health impacts from routine lab work.
Stannous chloride finds its place in water treatment and as a reducing agent. It helps maintain potable water supplies around the globe. Without this kind of chemistry, clean water would become a far steeper challenge in places already fighting scarcity and contamination.
Addressing Supply and Sustainability
I have watched suppliers face growing demand for tin-based compounds. Sourcing quality raw material, managing environmental impacts of mining, and meeting regulatory compliance keep the production of SnCl2 from becoming a free-for-all. Long-term, companies will need to improve recycling programs and explore new extraction methods. These steps help address resource strain and cut industrial waste.
Strong oversight, better labeling, and sharing of proper storage tips make storage and transport safer. Leaks or improper storage of stannous chloride anhydrous could harm both lab workers and the environment nearby. Training workers, offering clear safety sheets, and integrating spill protocols all play a part in limiting mishaps.
Practical Pathways Forward
Labs and industries walk a fine line managing chemical demand and safety. Promoting responsible use, investing in sustainable sourcing, and building smarter supply chains serve everyone in the long run. For students and professionals who rely on reliable chemistry, understanding the pure makeup of stannous chloride anhydrous—simply SnCl2—opens doors to success and safety alike.
Why Stannous Chloride Anhydrous Matters in Everyday Workplaces
Anyone using stannous chloride anhydrous for metal plating, tinning, or dyeing understands its value on the shop floor and in labs. The catch: this white, powdered chemical can act harshly on people and surroundings if handled carelessly. I’ve seen folks in labs and factories use this powder for years; every one of them talks about respect for a strong, reactive substance, not just its usefulness.
Personal Protection Cannot Be an Afterthought
Job safety starts the moment the drum opens. Skin contact leads to irritation, and breathing in dust risks long-term health impact. I always advise workers to treat every scoop of stannous chloride like it’s much stronger than it looks. Well-fitted gloves made from resistant material (nitrile does the trick), lab coats, chemical-resistant aprons, and fully covering goggles make a difference. For busy applications, a face shield can stop splashes from turning into burns. Even for a quick measure or transfer, skipping gloves or forgetting goggles sets a poor example and leaves workers open to injury.
Keeping the Air Clear
Stannous chloride dust has no place in your lungs. It can trigger coughing, sore throats, or worse. Well-ventilated workspaces have proven their worth where I’ve spent time. Fume hoods and exhaust systems capture fine particles before they drift. Poor airflow in older shops has sent too many to the sink with burning throats or stinging eyes. Workplace monitoring for tiny dust particles cost less in the long run than treating health complaints.
Smart Storage Protects Workers and Chemical Quality
This chemical won’t play nicely with water, strong acids, or oxidizers. I’ve heard stories from old-timers about cracked containers leaking powder into damp corners of a storeroom, or unexpected reactions with rusted metal. Storing stannous chloride in tightly sealed containers, away from humidity and reactive substances, foils those problems. Labels on every drum and jar tell everyone what’s inside before anyone lifts a lid. Training every person to put back lids tightly helps keep the air clean and prevents dangerous mixing.
Spill Response Is Everyone’s Job
No one plans for spills, but they happen anyway. A minor puff of dust during transfer, or a kicked-over jar, can quickly spiral. Every lab bench or plating line benefits from a ready spill kit—absorbent material, a dedicated broom and pan, and a place to dump waste. Workers knowing the cleanup drill matters more than fancy equipment. They learn to scoop spilled powder gently, bag it securely, and decontaminate surfaces using suitable, non-reactive cleaners instead of plain water.
Training Builds a Culture of Care
People I’ve worked with remember a time before well-written safety briefs and posters. These days, clear instruction and plenty of reminders foster safe habits. New staff do best shadowing experienced hands; peer-to-peer tips stick far better than a dusty manual. Management plays its part, keeping protective gear well-stocked, updating procedures, and listening to feedback from workers who spend hours around hazardous powders.
Final Thoughts: Shared Responsibility
Whether on a chemical line or in a research lab, handling stannous chloride anhydrous calls for more than caution; it draws on everyone doing the right thing, each shift, each day. The costs of shortcuts add up far faster than the effort needed for safe habits. By focusing on proven safety measures, up-to-date training, and clear communication, workplaces keep people healthy and productive while getting the most out of this useful, but demanding, compound.
| Names | |
| Preferred IUPAC name | Dichlorotin |
| Other names |
Stannous chloride
Tin(II) chloride Tin dichloride SnCl2 |
| Pronunciation | /ˈstæn.uːs ˈklɔː.raɪd ænˈhaɪ.drəs/ |
| Identifiers | |
| CAS Number | 7772-99-8 |
| Beilstein Reference | 1680837 |
| ChEBI | CHEBI:78029 |
| ChEMBL | CHEMBL1201577 |
| ChemSpider | 14018 |
| DrugBank | DB09138 |
| ECHA InfoCard | 100.029.220 |
| EC Number | 231-868-0 |
| Gmelin Reference | 86812 |
| KEGG | C14125 |
| MeSH | D013244 |
| PubChem CID | 24501 |
| RTECS number | XP7320000 |
| UNII | 97XQM7SJ51 |
| UN number | UN3260 |
| CompTox Dashboard (EPA) | DTXSID3023882 |
| Properties | |
| Chemical formula | SnCl2 |
| Molar mass | 169.62 g/mol |
| Appearance | White crystalline solid |
| Odor | Odorless |
| Density | 2.71 g/cm³ |
| Solubility in water | Soluble in water |
| log P | -0.89 |
| Vapor pressure | 0.7 mmHg (20°C) |
| Acidity (pKa) | -1.0 |
| Basicity (pKb) | 8.73 |
| Magnetic susceptibility (χ) | -66.0e-6 cm³/mol |
| Refractive index (nD) | 1.910 |
| Dipole moment | 2.95 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 142.5 J/(mol·K) |
| Std enthalpy of formation (ΔfH⦵298) | -578 kJ/mol |
| Pharmacology | |
| ATC code | V03AN02 |
| Hazards | |
| Main hazards | Harmful if swallowed. Causes severe skin burns and eye damage. May cause respiratory irritation. |
| GHS labelling | GHS02, GHS05, GHS07, GHS08 |
| Pictograms | GHS05,GHS07 |
| Signal word | Danger |
| Hazard statements | H302: Harmful if swallowed. H315: Causes skin irritation. H319: Causes serious eye irritation. H335: May cause respiratory irritation. |
| Precautionary statements | P264, P270, P273, P280, P301+P312, P330, P305+P351+P338, P337+P313, P304+P340, P403+P233, P501 |
| NFPA 704 (fire diamond) | 2-1-0-Acx |
| Autoignition temperature | **500°C (932°F)** |
| Explosive limits | Non-explosive |
| Lethal dose or concentration | LD50 oral rat 700 mg/kg |
| LD50 (median dose) | LD50 (median dose): Oral-rat LD50: 700 mg/kg |
| NIOSH | SN8225000 |
| PEL (Permissible) | PEL (Permissible): 2 mg/m³ (as Sn) |
| REL (Recommended) | 3 mg/m³ |
| IDLH (Immediate danger) | IDLH: 100 mg/m³ |
| Related compounds | |
| Related compounds |
Tin(II) chloride dihydrate
Tin(IV) chloride Tin(II) sulfate Tin(II) fluoride Tin(II) oxide |
