Aniline-2-Sulfonic acid stands out as a pivotal raw material in the chemical industry. Carrying the molecular formula C6H7NO3S, this compound lands under the chemical category of aromatic sulfonic acids. Its physical state ranges from pale solid crystals to powder and sometimes flakes, depending on processing methods and purity levels. Many labs and factories rely on this product for sulfonation reactions, direct dye synthesis, and various chemical modifications.
The density of Aniline-2-Sulfonic acid usually registers around 1.48 g/cm³ at room temperature. Most samples appear as off-white or greyish solids, but consistency can slide into yellowish hues due to trace impurities or storage conditions. Melting points sit near 288°C, demonstrating substantial thermal stability for heated applications. If you rub a small sample between your fingers—wearing gloves, of course—it feels granular or powdery, never slick or waxy. Water solubility isn’t high but sufficient for most practical lab uses. Bulk storage prefers flakes and crystalline powder forms, as these allow for controlled dispensing and easier handling during shipping.
Looking close, the structure places a sulfonic acid group (–SO3H) in the ortho position, right next to the amino group (–NH2) on the benzene ring. This orientation isn’t just textbook trivia—it influences reactivity, solubility, and bonding in chemical syntheses. For anyone working in dye chemistry, this specific arrangement helps with coupling reactions that create vivid, stable pigments for textiles and coatings. Molecular weight hits 173.19 g/mol, which matters for accurate dosing in large-batch processes.
From my own observation working alongside manufacturing chemists, you see Aniline-2-Sulfonic acid rack up importance in the fabric dye and pigment industries. Synthesis of azo dyes, for instance, leans heavily on this compound as a core building block. Pharmaceutical labs also depend on the same raw material as a precursor for sulfamides and other specialty chemicals. Leather processing outfits sometimes use its solutions for tanning treatments, which can surprise those who only link the material to bright colors in shirts and fabrics.
Commercial lots vary in presentation. Manufacturers supply Aniline-2-Sulfonic acid as crystalline solids, colorless or faintly colored, and sometimes as fine powders. Flakes provide easy batch weighing in large reactors. In rare cases, pearl granules help reduce dust loss if local regulations call for minimized airborne particulates. Liquids remain uncommon, but solutions occasionally hit the market in liter bottles tightly sealed to avoid moisture ingress.
Every batch of Aniline-2-Sulfonic acid includes a full property sheet. Density and melting point usually top the list—key information for those troubleshooting a reaction gone sideways or adjusting a mixing protocol. Spec sheets often mention solubility in hot water, stability under light, hygroscopic properties, and how the raw material can absorb ambient moisture. Keeping storage areas dry and cool preserves the acid’s structure and prevents long-term degradation. Real-world practice suggests stacking drums or bags on wooden pallets, never straight on warehouse floors, to evade any capillary rise of water that could damage the solids or boost the risk of hazardous reaction.
Chemists in trading companies pay steady attention to the HS Code 29214200 for Aniline-2-Sulfonic acid. This code streamlines paperwork for international shipments and customs clearance, reducing bottlenecks at borders. In today’s environment of tight delivery schedules and global supply chain pressure, accuracy in labeling and documentation, especially with hazardous substances, heads off major delays.
Despite its utility, Aniline-2-Sulfonic acid carries significant safety marks. It can irritate the skin and eyes on contact, and dust inhalation may trigger respiratory symptoms. Industrial setups require personal protective equipment like gloves, goggles, and well-fitting masks. Chemical compatibility checks prevent hazardous reactions with oxidizers or strong bases. Spills need quick cleanup—wash down with plenty of water, neutralize residues, and ventilate affected areas. Disposal has to follow local regulations for hazardous materials because breakdown in municipal systems could release hazardous loads. Environmental officers double-check effluent facilities, ensuring no accidental introduction of aromatic sulfonic acids into water streams. In small-scale lab use, practitioners quickly learn the value of well-maintained chemical fume hoods and careful weighing techniques that minimize powder dispersal.
Safe handling remains a priority, with ongoing upgrades in packaging material, solid containment, and end-user training. Rising concern about aquatic toxicity and chemical persistence has prompted some producers to develop more eco-friendly substitutes where possible, though the unique structure of Aniline-2-Sulfonic acid can be tough to replicate in advanced syntheses. Regulatory agencies watch the market for better labeling, improved data sheets, and wider education about risk controls. In practice, switching from bulk bags to smaller tamper-evident containers often reduces accident rates and improves tracking. Introducing workplace safety drills—not just for spills but also for accidental exposure—changes the company culture and reduces harm. Sharing information with industry peers and regulatory boards adds to a broader knowledge base that keeps everyone safer and helps minimize legal or operational setbacks down the line.
