Chemical Compatibility

Acetaldehyde (CH₃CHO, CAS 75-07-0) is a colorless, extremely flammable liquid with a sharp, fruity odor. It has a specific gravity of about 0.79, boils at only 68°F (20°C) and has a flash point near -36°F (-38°C). It is used as a chemical intermediate for pyridines, pentaerythritol, peracetic acid and acetate esters, and in small amounts as a flavoring. Bulk acetaldehyde storage needs cool, vented, inerted tanks away from ignition sources. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Acetate Solvent refers to ester solvents such as ethyl acetate, n-propyl acetate and n-butyl acetate, or blends of them. These are clear, flammable liquids with a sweet, fruity odor and a specific gravity of about 0.9. Acetate solvents are widely used in paints, coatings, printing inks, adhesives, nail polish and cleaning products because they evaporate quickly and dissolve resins well. Storage tanks need grounding, vapor control and protection from ignition sources. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Alum (Aluminum Sulfate) (Al₂(SO₄)₃, CAS 10043-01-3) is usually supplied as liquid alum, a clear to pale amber acidic solution of about 48% with a specific gravity near 1.33. It is one of the most common coagulants in drinking water and wastewater treatment, and is also used in paper sizing, phosphorus removal and soil pH control. Liquid alum storage tanks should resist mild acid and avoid freezing below about 0°F. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Aluminum Sulfate Safety Data Sheet (SDS) – USALCO

Amines are organic nitrogen compounds derived from ammonia, including ethanolamines (MEA, DEA, MDEA), ethyleneamines and alkylamines. Most are alkaline, many are corrosive to skin and some are flammable; this entry reflects a heavier amine solution with a specific gravity of about 1.13. Amines are used in gas sweetening (H₂S and CO₂ removal), corrosion inhibitors, surfactants, epoxy curing agents and pharmaceuticals. Confirm the specific amine before selecting tank materials. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Ammonia 10% (Aqua Ammonia) is ammonium hydroxide (NH₄OH, CAS 1336-21-6), a clear solution of ammonia gas in water with a strong pungent odor and a specific gravity of about 0.96. It is used for pH control, household and industrial cleaners, SCR and SNCR NOx control, chloramine formation in water treatment, and fertilizer. Aqua ammonia tanks should be closed and vented to control ammonia vapor release. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Ammonium Hydroxide Safety Data Sheet (SDS) – Tanner Industries

Ammonium Chloride 25% (NH₄Cl, CAS 12125-02-9) solution is a clear, mildly acidic salt solution with a specific gravity of about 1.07. Ammonium chloride is used as a galvanizing and soldering flux, in metal finishing, dry-cell batteries, fertilizers, and as a clay stabilizer in oilfield fracturing and completion fluids. It is corrosive to many metals, so non-metallic storage tanks are commonly used. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Amyl Alcohol (pentanol, C₅H₁₁OH; n-amyl alcohol CAS 71-41-0) is a colorless liquid with a mild, fusel-oil odor, a specific gravity of about 0.815, a boiling point near 280°F (138°C) and a flash point near 120°F (49°C). It is used as a solvent, as a raw material for amyl acetate and other flavor esters, in plasticizers, ore flotation and pharmaceuticals. Store in closed, grounded tanks away from heat and oxidizers. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Amyl Chloride (1-chloropentane, C₅H₁₁Cl, CAS 543-59-9) is a colorless, flammable chlorinated hydrocarbon with a specific gravity of about 0.88 and a boiling point near 226°F (108°C). It is used as an industrial solvent and as an intermediate in making amyl mercaptans, amines and other organic chemicals. Chlorinated solvents can swell some plastics and elastomers, so material selection matters for amyl chloride storage. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Antifreeze (Glycol Based) is most often an ethylene glycol (CAS 107-21-1) solution with corrosion inhibitors and dye, a sweet-tasting, toxic liquid with a specific gravity of about 1.11 to 1.15. Glycol antifreeze is used as engine coolant and as a heat transfer fluid in HVAC chillers, geothermal and process cooling loops. Bulk antifreeze storage and used coolant collection tanks should be labeled and secured, since ethylene glycol is poisonous if swallowed. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Barium Chloride (BaCl₂, CAS 10361-37-2) is a white, water-soluble salt usually stored as a clear solution. It is toxic if swallowed. It is used to remove sulfate from brine in chlor-alkali plants, and in pigments, heat-treating salts, PVC stabilizers and laboratory analysis. Barium chloride solution tanks should be clearly labeled and kept separate from sulfates and acids. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Barium Chloride Solution Safety Data Sheet (SDS) – Chemical Products Corp.

Beer is a fermented beverage of malted grain, hops, yeast and water, typically 4% to 6% alcohol by volume, with dissolved CO₂, a pH around 4 to 4.5 and a specific gravity just above 1.0. Breweries and distributors store beer, wort and brewing water in food-grade tanks for fermentation, conditioning and serving. Beer storage needs food-contact materials, sanitary fittings and cleaning access. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Benzene (C₆H₆, CAS 71-43-2) is a clear, highly flammable aromatic hydrocarbon with a sweet odor, a specific gravity of about 0.876, a boiling point of 176°F (80°C) and a flash point near 12°F (-11°C). It is a known human carcinogen. Benzene is a major feedstock for ethylbenzene and styrene, cumene and phenol, cyclohexane and nylon, and detergents. Benzene storage is tightly regulated and needs vapor-controlled, grounded tanks. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Benzene Sulfonic Acid (C₆H₅SO₃H, CAS 98-11-3) is a strong organic acid, commonly handled as a viscous solution with a specific gravity of about 1.3. It is corrosive to skin and metals. It is used as an acid catalyst for resins and esterification, and as an intermediate for phenol, resorcinol, detergents and pharmaceuticals. Tanks for benzene sulfonic acid must resist strong acid. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Benzyl Alcohol (C₆H₅CH₂OH, CAS 100-51-6) is a colorless liquid with a faint, pleasant aromatic odor, a specific gravity of about 1.044, a boiling point near 401°F (205°C) and a flash point near 200°F (93°C). It is used as a solvent in paint strippers, coatings, inks and epoxy systems, and as a preservative in cosmetics and injectable drugs. Benzyl alcohol can soften some plastics and elastomers. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Boric Acid (H₃BO₃, CAS 10043-35-3) is a white crystalline solid (density about 1.51) that dissolves slowly in water, about 5% at room temperature and more when heated, to form a very weak acid. It is used in fiberglass and borosilicate glass, flame retardants, nuclear reactor coolant control, wood preservatives, insecticides and mild antiseptics. Boric acid solutions are usually stored warm or dilute to prevent crystals settling out. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Bromine (Br₂, CAS 7726-95-6) is a dense, dark red-brown fuming liquid with a specific gravity of about 3.1 and a boiling point of 138°F (59°C). It is highly toxic, corrosive and a strong oxidizer. Bromine is used to make brominated flame retardants, clear brine drilling fluids, water treatment biocides, pharmaceuticals and agricultural chemicals. Because of its weight and reactivity, bromine needs specially engineered containment. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Butyl Amine (n-butylamine, C₄H₉NH₂, CAS 109-73-9) is a colorless, highly flammable liquid with a strong ammonia-like odor, a specific gravity of about 0.74, a boiling point near 172°F (78°C) and a flash point near 10°F (-12°C). It is corrosive to skin and eyes. Butylamine is used to make rubber vulcanization accelerators, pesticides, pharmaceuticals, dyes and emulsifiers. Store in grounded, vented tanks away from acids and oxidizers. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Calcium Chloride (30% in Water) (CaCl₂, CAS 10043-52-4) solution is a clear, colorless to slightly cloudy brine with a specific gravity of about 1.30 that stays liquid well below 0°F. It is used for road deicing and anti-icing, dust control, road base stabilization, concrete set acceleration, refrigeration brines, and oilfield completion fluids. Liquid calcium chloride is corrosive to steel, so poly storage tanks are widely used. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Liquid Calcium Chloride Safety Data Sheet (SDS) – OxyChem

Calcium Chloride (Saturated) is a concentrated CaCl₂ brine near its solubility limit, around 40% to 45% depending on temperature, with a specific gravity of about 1.43. It is heavier than standard 30% liquid calcium chloride. Saturated brine is used as a dense oilfield completion and workover fluid, for ballast, in industrial drying and in high-strength deicing blends. Crystals can form as the temperature drops, so tanks may need heating or periodic mixing. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Liquid Calcium Chloride Safety Data Sheet (SDS) – OxyChem

Calcium Hydroxide (50%) (hydrated lime slurry, Ca(OH)₂, CAS 1305-62-0) is a white, strongly alkaline suspension (pH about 12.4) with a specific gravity of about 1.38. Liquid lime is used for water softening and pH adjustment, acid wastewater neutralization, sludge stabilization, flue gas scrubbing and mining. Lime slurry settles quickly, so storage tanks need agitation or recirculation and large, low-placed outlets. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Liquid Calcium Hydroxide (Lime Slurry) Safety Data Sheet (SDS) – Mississippi Lime

Carbolic Acid (Phenol) (C₆H₅OH, CAS 108-95-2) is a colorless to pink crystalline solid that melts at about 106°F (41°C), so it is shipped molten or as liquefied phenol (about 90% with water). It is toxic and is rapidly absorbed through the skin. Phenol is used to make bisphenol A, phenolic resins, caprolactam for nylon, alkylphenols and disinfectants. Phenol storage often requires heated, insulated tanks; check the temperature limits of each resin. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Carbonic Acid (H₂CO₃) forms when carbon dioxide dissolves in water. It is a weak acid with a pH of about 3.7 to 4 in carbonated water, and it releases CO₂ gas when pressure drops or temperature rises. It is found in carbonated beverages and soda water, and in water treatment for pH reduction and remineralization. Carbonated liquids in non-pressurized tanks lose their CO₂ over time and need proper venting. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Caustic Potash 45% (potassium hydroxide, KOH, CAS 1310-58-3) is a clear, colorless, strongly alkaline solution with a specific gravity of about 1.45. It is corrosive to skin and eyes and attacks aluminum and zinc. Liquid caustic potash is used for liquid soaps and detergents, potassium fertilizers and chemicals, biodiesel catalysts, alkaline batteries and food processing. It freezes at a lower temperature than caustic soda. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Potassium Hydroxide 30–55% Safety Data Sheet (SDS) – Olin

Caustic Soda (50%) (sodium hydroxide, NaOH, CAS 1310-73-2) is the most common form of liquid caustic, a clear, viscous, strongly alkaline solution with a specific gravity of about 1.52. It begins to crystallize near 54°F (12°C), so outdoor tanks are often insulated and heated. 50% caustic soda is used in pulp and paper, alumina refining, soaps, textiles, water treatment pH control and chemical manufacturing. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Caustic Soda Solution Safety Data Sheet (SDS) – Formosa Plastics USA

Caustic Soda (80%) is very concentrated sodium hydroxide (NaOH, CAS 1310-73-2). At this strength caustic is solid at room temperature, so it is handled hot or molten, or as flake and bead caustic that is dissolved on site. It is used where water must be kept to a minimum, such as in specialty chemical synthesis and in making high-strength cleaners. Because it is stored at elevated temperatures, check each tank resin's temperature limit. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Caustic Soda Solution Safety Data Sheet (SDS) – Formosa Plastics USA

Chlorine Water is a dilute solution of chlorine in water containing hypochlorous acid (HOCl) and hydrochloric acid. It has a yellow-green tint and a strong chlorine odor. It is a powerful oxidizer and disinfectant, produced in chlorinators, scrubbers and chlor-alkali processes. It is used for water disinfection, bleaching, and metal and mineral processing. Chlorine water tanks need vapor control because chlorine gas escapes from solution. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Chlorine Safety Data Sheet (SDS) – Olin

Chlorine, Anhydrous Liquid (Cl₂, CAS 7782-50-5) is a greenish-yellow, highly toxic gas that is shipped as a liquid under pressure. It boils at -29°F (-34°C) and has a liquid specific gravity of about 1.47. It is used in water disinfection, PVC production, titanium dioxide, pulp bleaching and many chemicals. Anhydrous chlorine must be kept in rated pressure vessels such as cylinders, ton containers and rail cars, not atmospheric storage tanks. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Chlorine Safety Data Sheet (SDS) – Olin

Citric Acid (C₆H₈O₇, CAS 77-92-9) is a white crystalline organic acid made by fermentation. It is very soluble in water and often supplied as a 50% solution with a specific gravity of about 1.24. It is used as a food and beverage acidulant, a chelating agent in cleaners and detergents, for descaling and metal passivation, and in pharmaceuticals and cosmetics. Food-grade citric acid storage requires food-contact tank materials. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Copper Chloride (cupric chloride, CuCl₂, CAS 7447-39-4) is usually stored as a green to blue-green acidic solution. It is corrosive and very toxic to aquatic life. Cupric chloride is used as an etchant for printed circuit boards, as a catalyst in chemical synthesis, in wood preservatives, pigments and textile dyeing. Spent etchant is commonly collected for copper recovery, and containment helps prevent releases. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Crude Oil (Texas) is unrefined petroleum, a mixture of hydrocarbons with a specific gravity of about 0.876 (roughly 30° API) for this entry; light sweet West Texas crudes are lighter. It is flammable, may contain hydrogen sulfide and dissolved gases, and often carries produced water and sediment. Crude oil is stored in lease tank batteries, gathering systems and terminals before refining into fuels and petrochemicals. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Diesel Fuel is a middle-distillate petroleum fuel, a mixture of C10–C20 hydrocarbons with a specific gravity of about 0.85 to 0.88 and a minimum flash point of 125°F (52°C), which makes it combustible. Ultra low sulfur diesel (ULSD) powers trucks, farm and construction equipment, generators and locomotives, and No. 2 fuel oil is used for heating. Diesel storage tanks need secondary containment, venting and protection from water contamination. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: No. 2 Ultra Low Sulfur Diesel Safety Data Sheet (SDS) – Marathon Petroleum

Disodium Phosphate (Na₂HPO₄, CAS 7558-79-4) is a white, water-soluble salt that forms mildly alkaline solutions (pH about 9). It is used as an emulsifier and buffer in processed cheese and foods, in boiler and cooling water treatment, detergents, textile processing and pharmaceutical buffers. Disodium phosphate solutions are not very corrosive, but food-grade service needs food-contact tank materials. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Ethanol (ethyl alcohol, C₂H₅OH, CAS 64-17-5) is a clear, colorless, flammable liquid with a specific gravity of about 0.789, a boiling point of 173°F (78°C) and a flash point of about 55°F (13°C). Ethanol is blended into gasoline (E10, E85), and is used as a solvent, in hand sanitizers and disinfectants, beverages, pharmaceuticals and extracts. Ethanol tanks need grounding, vapor venting and fire protection. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Ethyl Acetate (C₄H₈O₂, CAS 141-78-6) is a clear, highly flammable ester solvent with a sweet, fruity odor, a specific gravity of about 0.90, a boiling point of 171°F (77°C) and a flash point near 24°F (-4°C). It is one of the most widely used solvents for coatings, flexible packaging inks, adhesives, nail polish remover, pharmaceutical extraction and decaffeination. Ethyl acetate tanks need grounding, vapor control and fire protection. Typical recommendation: HDPE tank, PP fittings, EPDM gaskets. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Ferric Sulfate 60% (Fe₂(SO₄)₃, CAS 10028-22-5) is a reddish-brown, strongly acidic solution with a specific gravity of about 1.59. It is an effective coagulant for drinking water and wastewater treatment, phosphorus removal, sludge conditioning and odor (hydrogen sulfide) control. Ferric sulfate stains and corrodes steel and concrete, so plastic storage tanks with containment are common. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Ferrous Sulfate (20%) (FeSO₄, CAS 7720-78-7) solution is a pale green, mildly acidic liquid with a specific gravity of about 1.2. It is used in wastewater phosphorus removal and odor control, hexavalent chromium reduction, as an iron fertilizer and lawn treatment, in animal feed and pigment manufacture. It slowly oxidizes in air to ferric iron, which can cause rust-colored deposits. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Formic Acid (HCOOH, CAS 64-18-6) is a clear, colorless liquid with a sharp, pungent odor, a specific gravity of about 1.22 (85% to 99% grades) and a boiling point near 214°F (101°C). It is corrosive and combustible. Formic acid is used in leather tanning, textile dyeing, silage and feed preservation, rubber latex coagulation, de-icing formates and oilfield acidizing. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Hydraulic Oil (Petroleum) is a mineral-oil based fluid with anti-wear, anti-foam and oxidation-inhibiting additives. It has a specific gravity of about 0.86 to 0.88 and a high flash point, often above 400°F (204°C). It transmits power in hydraulic presses, injection molding machines, mobile equipment and lifts. Bulk hydraulic oil and used oil tanks need secondary containment and protection from water and dirt. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Hydraulic Oil (Synthetic) includes polyalphaolefin (PAO), synthetic ester, polyalkylene glycol and phosphate ester fluids chosen for wide temperature ranges, fire resistance or biodegradability. Specific gravity ranges from about 0.85 to 1.15 depending on chemistry. These fluids are used in aircraft, steel mills, turbines, die casting and environmentally sensitive equipment. Phosphate esters can attack some elastomers, so gasket choice matters. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Iodine (I₂, CAS 7553-56-2) is a dense, blue-black crystalline solid (density about 4.9) that sublimes into a violet vapor and dissolves only slightly in water. Much of the U.S. supply comes from Oklahoma brines. Iodine is used in X-ray contrast media, disinfectants and povidone-iodine, animal feed supplements, LCD polarizing film and catalysts. Liquid storage usually involves iodine solutions or iodophors, which stain and are oxidizing. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Isooctane (2,2,4-trimethylpentane, C₈H₁₈, CAS 540-84-1) is a clear, highly flammable hydrocarbon with a specific gravity of about 0.69, a boiling point of 211°F (99°C) and a flash point near 10°F (-12°C). It defines 100 on the octane scale and is used as a high-octane gasoline blending component, reference fuel and laboratory solvent. Isooctane storage needs grounding, vapor control and fire protection. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Magnesium Chloride (31%) (MgCl₂, CAS 7786-30-3) brine is a clear to light amber liquid with a specific gravity of about 1.29 to 1.38, often harvested from the Great Salt Lake. It is used for road deicing and anti-icing, dust control on unpaved roads, as a magnesium source in agriculture and supplements, and in oxychloride cements. Liquid magnesium chloride storage tanks should be agitated occasionally to limit settling. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Magnesium Chloride Safety Data Sheet (SDS) – Compass Minerals

Magnesium Hydroxide Liquid 60% (Mg(OH)₂ slurry, CAS 1309-42-8) is a thick, white suspension with a specific gravity of about 1.5 to 1.6 and a pH near 10.5. It is a safer-to-handle alternative to caustic soda for acid wastewater neutralization, and is used for sewer odor and corrosion control, metals precipitation and as an antacid ingredient. The slurry settles, so tanks need mixing or recirculation and bottom outlets. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: FloMag H Magnesium Hydroxide Slurry Safety Data Sheet (SDS) – Martin Marietta Magnesia Specialties

Methanol (CH₃OH, CAS 67-56-1) is a clear, colorless, flammable liquid with a specific gravity of about 0.79, a boiling point of 149°F (65°C) and a flash point of about 52°F (11°C). It is toxic if swallowed, inhaled or absorbed through the skin. Methanol is a building block for formaldehyde, acetic acid and olefins, and is used in biodiesel production, windshield washer fluid, fuel blending and as a carbon source for wastewater denitrification. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Methanol Safety Data Sheet (SDS) – Methanex

Methyl Alcohol (wood alcohol, CH₃OH, CAS 67-56-1) is the simplest alcohol. It is volatile and burns with a nearly invisible flame. Methyl alcohol is poisonous, and swallowing small amounts can cause blindness. It is used as an industrial solvent, antifreeze in gas pipelines and windshield fluid, a denaturant for ethanol, and in the chemical, plastics and pharmaceutical industries. Storage tanks need grounding, flame arrestors and secure venting. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Methanol Safety Data Sheet (SDS) – Methanex

Mineral Oil (white oil, CAS 8042-47-5) is a highly refined, colorless, odorless petroleum oil with a specific gravity of about 0.83 to 0.89 and a high flash point. Food and pharmaceutical grades are used as release agents, laxatives and in cosmetics and baby oil; technical grades are used as lubricants, transformer and dielectric fluids, and in plastics processing. Mineral oil storage needs containment but little special handling. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Motor Oil is engine lubricant made from mineral or synthetic base oils blended with detergents, dispersants, viscosity modifiers and anti-wear additives such as ZDDP. It has a specific gravity of about 0.86 to 0.88 and a high flash point. Shops, fleets and dealerships store new motor oil in bulk dispensing tanks and collect used oil for recycling. Used oil tanks need secondary containment and labeling. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Nitric Acid (20%) (HNO₃, CAS 7697-37-2) is a clear, colorless, corrosive and oxidizing acid solution with a specific gravity of about 1.115. Dilute nitric acid is used for stainless steel passivation and pickling, metal etching and cleaning, clean-in-place (CIP) rinses in dairy and food plants, and laboratory work. It attacks many metals and organic materials. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Nitric Acid Safety Data Sheet (SDS) – LSB Industries

Nitric Acid (50%) (HNO₃, CAS 7697-37-2) is a strong oxidizing mineral acid with a specific gravity of about 1.31 to 1.36 that may give off reddish-brown nitrogen oxide fumes. It is used to make ammonium nitrate fertilizer, explosives, nitrocellulose and adipic acid, for metal treating and etching, and as a cleaning acid. Strong nitric acid degrades many plastics and elastomers over time, so material selection is critical. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Nitric Acid Safety Data Sheet (SDS) – LSB Industries

Nitrous Acid (HNO₂, CAS 7782-77-6) is a weak, unstable acid that exists only in cold, dilute aqueous solution. It is normally made on site by mixing sodium nitrite with a mineral acid and used immediately. It decomposes to nitric oxide and nitrogen dioxide fumes. It is used in diazotization reactions to make azo dyes and pigments, and in some pharmaceutical synthesis. Storage is short-term, in cool, vented tanks. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Nitrous Acid solutions are formed when nitrite salts are acidified or when nitrogen oxides dissolve in water, as in NOx scrubbers. HNO₂ is pale blue in solution and breaks down quickly into nitric acid, nitric oxide and water, especially when warm or concentrated. Industrial uses include dye and pigment chemistry, metal surface treatment and laboratory analysis. Tanks handling nitrous acid streams should be well vented to release toxic NOx gases. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Olive Oil is a vegetable oil pressed from olives, made up mainly of oleic acid triglycerides, with a specific gravity of about 0.91 and a pale yellow to green color. It is used in cooking and food production, cosmetics, soaps and pharmaceuticals. Bulk olive oil storage needs food-grade, opaque or covered tanks to protect it from light, heat and air, which cause rancidity. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Palm Oil is an edible vegetable oil from the fruit of the oil palm. It is semi-solid at room temperature, melts at about 95°F (35°C), and has a specific gravity of about 0.89 to 0.92. It is used in cooking oils, margarine, baked goods, soaps, cosmetics, biodiesel and oleochemicals. Bulk palm oil tanks are often heated to keep it pumpable, so check each tank resin's temperature limit. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Phthalic Acid (C₆H₄(COOH)₂, CAS 88-99-3) is a white crystalline aromatic dicarboxylic acid that is only slightly soluble in cold water. It is more commonly handled as phthalic anhydride. It is an intermediate for phthalate plasticizers used in flexible PVC, alkyd and polyester resins, dyes and pigments. Phthalic acid solutions are mildly acidic and typically stored warm or dilute. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Cadmium Cyanide Plating Solution (90°F) is an alkaline electroplating bath containing cadmium oxide, sodium cyanide and sodium hydroxide, typically run at about 70°F to 90°F. It deposits a corrosion-resistant cadmium coating on steel fasteners, aerospace and military parts. The bath is extremely toxic, and contact with acid releases deadly hydrogen cyanide gas. Plating tanks must be kept separate from acids and have full secondary containment. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Potassium Acetate 50% (CH₃COOK, CAS 127-08-2) solution is a clear, mildly alkaline liquid (pH about 10 to 11) with a specific gravity of about 1.27 to 1.30. It is a low-corrosion, chloride-free deicer for airport runways and bridges, a low-temperature heat transfer fluid, and a food preservative (E261). Do not store potassium acetate deicers in galvanized, zinc or brass systems. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Potassium Hydroxide (Caustic Potash) (KOH, CAS 1310-58-3) is a strong alkali sold as white flakes or pellets and as 45% to 50% liquid with a specific gravity of about 1.45 to 1.50. It is highly corrosive to skin and eyes, generates heat when diluted and attacks aluminum, zinc and tin. KOH is used for liquid soaps, potassium carbonate and phosphates, fertilizers, alkaline battery electrolyte, biodiesel and food processing. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Potassium Hydroxide 30–55% Safety Data Sheet (SDS) – Olin

Potassium Hydroxide 50% (KOH, CAS 1310-58-3) is a clear, colorless, strongly caustic solution with a specific gravity of about 1.50. It stays liquid at lower temperatures than 50% caustic soda, which makes it easier to store outdoors in cold climates. Liquid KOH is used in detergent and soap making, potassium chemicals, de-icers, oil and gas processing, metal cleaning and pH control. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Potassium Hydroxide 30–55% Safety Data Sheet (SDS) – Olin

Potassium Hypochlorite (KOCl, CAS 7778-66-7) is a pale yellow, alkaline bleach solution with a chlorine odor and a specific gravity of about 1.16. It is a sodium-free disinfectant used for water treatment, agriculture and irrigation, food plant sanitation and surface disinfection. Like other hypochlorites, it breaks down with heat, sunlight and metal contamination, so tanks should be opaque, vented and kept cool. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Propyl Acetate (n-propyl acetate, C₅H₁₀O₂, CAS 109-60-4) is a clear, flammable ester solvent with a pear-like odor, a specific gravity of about 0.89, a boiling point of 215°F (102°C) and a flash point near 55°F (13°C). It is widely used in flexographic and gravure printing inks, coatings, adhesives, nail care products and fragrances. Store in grounded tanks with vapor control. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Propyl Alcohol (n-propanol, C₃H₇OH, CAS 71-23-8) is a clear, flammable alcohol with a specific gravity of about 0.80, a boiling point of 207°F (97°C) and a flash point near 59°F (15°C). Its isomer, isopropyl alcohol, is often called propyl alcohol in everyday use. Both are used as solvents for printing inks, coatings, cleaners and disinfectants, and as chemical intermediates. Propyl alcohol tanks need grounding and fire protection. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Propylene Glycol (C₃H₈O₂, CAS 57-55-6) is a clear, odorless, slightly viscous liquid with a specific gravity of about 1.036, a boiling point of 370°F (188°C) and low toxicity. USP grade is used in foods, pharmaceuticals and cosmetics, and industrial grades are used as food-safe antifreeze, heat transfer fluid, aircraft deicer and in polyester resins. Propylene glycol storage is straightforward, with food-grade tanks for USP service. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Propylene Glycol USP Safety Data Sheet (SDS) – BASF

Salt Brine (NaCl Saturated) is a solution of sodium chloride (CAS 7647-14-5) in water at about 26%, with a specific gravity of about 1.2 and a freezing point near -6°F (-21°C). Brine is used for road anti-icing and pre-wetting, water softener regeneration, food pickling and brining, hide curing and oilfield fluids. Salt brine corrodes steel, which is why highway departments and softener systems commonly use poly brine tanks. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sodium Bisulfate (NaHSO₄, CAS 7681-38-1) is a dry acid that forms strongly acidic solutions with a specific gravity of about 1.36. It is used to lower pH in swimming pools and spas, in metal finishing and cleaning products, as a food acidulant, for poultry litter treatment and in toilet bowl cleaners. Sodium bisulfate solutions are corrosive to steel and concrete. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sodium Bisulfite (NaHSO₃, CAS 7631-90-5) is usually supplied as a 38% to 40% yellowish solution with a sulfur dioxide odor and a specific gravity of about 1.33 to 1.48. It is used for dechlorination of water and wastewater, as an oxygen scavenger, to reduce hexavalent chromium, as a food preservative, and in pulp, textile and photographic processing. Tanks should be closed and vented, since SO₂ off-gasses. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Sodium Bisulfite Safety Data Sheet (SDS) – INEOS Calabrian

Sodium Bromide (NaBr, CAS 7647-15-6) is a white, highly soluble salt usually stored as a 40% to 46% clear solution with a specific gravity of about 1.4 to 1.5. Combined with chlorine or bleach, it forms hypobromous acid, a biocide for cooling towers, pools and spas. It is also used in clear brine oilfield completion fluids, pharmaceuticals and photography. Sodium bromide solutions are near neutral but corrode steel once wet. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sodium Bromide – Nalco Actibrom 1318 is a sodium bromide-based water treatment product from Nalco Water (Ecolab) with a specific gravity of about 1.45. It is fed with chlorine or hypochlorite to generate hypobromous acid on site, giving strong biofouling and microbiological control in cooling towers and industrial water systems, especially at higher pH. Follow the supplier's feed and storage guidance for this product. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sodium Hydroxide (50%) (NaOH, CAS 1310-73-2) is a clear, highly corrosive alkaline solution with a specific gravity of about 1.53 that is made in the chlor-alkali process alongside chlorine. It is used in water and wastewater pH control, chemical manufacturing, pulp and paper, aluminum processing, food processing, soaps and cleaning chemicals. Because 50% NaOH starts to freeze near 54°F (12°C), outdoor sodium hydroxide tanks are often heat traced and insulated. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Sodium Hydroxide Solution Safety Data Sheet (SDS) – Formosa Plastics USA

Sodium Hydroxide (80%) (NaOH, CAS 1310-73-2) at this concentration is a dense, strongly caustic material with a specific gravity near 1.9 that is solid at ambient temperature and must be kept hot to stay liquid. It is used in specialty chemical manufacturing and where adding water is undesirable. Because of the high storage temperatures and severe corrosivity, confirm the temperature limits of each tank resin before choosing a tank. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Sodium Hydroxide Solution Safety Data Sheet (SDS) – Formosa Plastics USA

Sodium Nitrate (NaNO₃, CAS 7631-99-4) is a white, highly water-soluble salt and an oxidizer. It is used in fertilizers, explosives and pyrotechnics, glass and enamel manufacturing, molten salt heat transfer and solar thermal storage, metal treating, and as a food preservative. Sodium nitrate solutions should be kept away from combustible materials and reducing agents. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Soybean Oil is an edible vegetable oil pressed from soybeans, rich in linoleic acid, with a specific gravity of about 0.92 and a high flash point. It is used for cooking oils, margarine and processed foods, biodiesel, printing inks, paints, epoxidized plasticizers and lubricants. Bulk soybean oil storage needs food-grade, covered tanks to limit oxidation and moisture. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sulfur Chloride (sulfur monochloride, S₂Cl₂, CAS 10025-67-9) is a yellow to amber fuming liquid with a choking odor, a specific gravity of about 1.6 to 1.7 and a boiling point near 280°F (138°C). It reacts violently with water, releasing hydrogen chloride, sulfur dioxide and sulfur. It is used in rubber vulcanization, lubricant additives, insecticides and chemical synthesis. Tanks must be dry, sealed and protected from moisture. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Sulfur Dioxide (SO₂, CAS 7446-09-5) is a colorless, toxic gas with a sharp, choking odor that boils at 14°F (-10°C) and is shipped as a liquid under pressure. Dissolved in water it forms sulfurous acid. SO₂ is used for dechlorination, wine and food preservation, pulp bleaching, metal ore processing and sulfite manufacture. Anhydrous SO₂ requires pressure vessels, while dilute sulfurous acid can be held in vented tanks. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Sulfur Dioxide Safety Data Sheet (SDS) – INEOS Calabrian

Tannic Acid (C₇₆H₅₂O₄₆, CAS 1401-55-4) is a yellow-brown plant polyphenol that dissolves readily in water to form a mildly acidic, astringent solution. It is used in leather tanning, wine and beer clarification, dye mordants, inks, corrosion inhibitors (rust converters) and oilfield drilling fluids. Tannic acid darkens when it contacts iron, so non-metallic tanks are preferred. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Toluene (methylbenzene, C₇H₈, CAS 108-88-3) is a clear, highly flammable aromatic solvent with a sweet odor, a specific gravity of about 0.87, a boiling point of 231°F (111°C) and a flash point near 40°F (4°C). It is used in paints, coatings, adhesives and thinners, gasoline blending, and to make benzene, xylenes and TDI for polyurethanes. Aromatic solvents swell many plastics and elastomers. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Trichloroacetic Acid (TCA, CCl₃COOH, CAS 76-03-9) is a white, moisture-absorbing crystalline solid that melts near 135°F (57°C) and dissolves to form a strong, corrosive acid. It is used in laboratories to precipitate proteins and DNA, in medical chemical peels and wart removal, and as a reagent in organic synthesis. TCA solutions cause severe burns, so storage requires corrosion-resistant tanks and fittings. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Triethylamine (TEA, (C₂H₅)₃N, CAS 121-44-8) is a clear, highly flammable liquid with a strong fishy-ammonia odor, a specific gravity of about 0.73, a boiling point of 192°F (89°C) and a flash point near 20°F (-7°C). It is used as a catalyst in foundry cold-box core making, as an acid scavenger in pharmaceutical and agrochemical synthesis, and to make quaternary ammonium compounds. Triethylamine tanks need grounding and vapor control. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Safety data: Triethylamine Safety Data Sheet (SDS) – Eastman

Urea (CO(NH₂)₂, CAS 57-13-6) is a white, very soluble nitrogen compound. Urea solutions include 32.5% diesel exhaust fluid (DEF/AdBlue) for SCR emissions systems, UAN and other liquid fertilizers, and feedstock for urea-formaldehyde resins and adhesives. Urea solutions crystallize in cold weather and can corrode copper and brass, so poly storage tanks are common in DEF and fertilizer service. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Uric Acid (C₅H₄N₄O₃, CAS 69-93-2) is a white, nearly water-insoluble compound formed when the body breaks down purines. It is a main nitrogen component of bird and reptile droppings. In storage tanks it mainly appears in animal waste, poultry processing and biological wastewater streams, where it can settle as sludge. Wastes containing uric acid are mildly acidic and are usually handled like other organic wastewater. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Vinegar is a dilute solution of acetic acid (CH₃COOH), usually 4% to 8% for table vinegar and up to 20% or more for industrial and cleaning vinegar, made by fermenting ethanol. It has a pH of about 2.4 to 3 and a specific gravity just above 1.0. It is used in food processing, pickling, condiments and sauces, natural cleaners and agriculture. Vinegar storage needs food-grade tanks and acid-resistant fittings. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Waste Water covers a wide range of industrial and municipal process water, rinse water and runoff that may contain dissolved salts, acids or alkalis, oils, solids and organic matter. Wastewater tanks are used for collection, equalization, pH neutralization, settling and holding before treatment or disposal. Because composition varies, identify the worst-case chemicals, pH and temperature before selecting a wastewater storage tank. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Water (H₂O, CAS 7732-18-5) is a clear, odorless liquid with a specific gravity of 1.00 that freezes at 32°F (0°C). It is stored for process and cooling water, fire protection, rainwater harvesting, irrigation and livestock, construction and dust control. Water storage tanks should be UV-stabilized and opaque to limit algae growth, and properly vented and drained. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Hot Water (up to 200°F) is water stored or processed at elevated temperatures, up to about 200°F (93°C), for washdown, cleaning, boiler feed, process heating and heat recovery systems. At these temperatures plastics lose strength, so tank resin, wall thickness, fittings and gaskets must be rated for continuous hot service. Standard HDPE tanks are not intended for continuous water above about 120°F (49°C). Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Potable Water is drinking water treated to meet EPA Safe Drinking Water Act standards. Potable water storage tanks are used for homes, ranches, emergency supply, RV and remote sites, food plants and municipal systems. Tanks should be made from resin certified to NSF/ANSI 61 or FDA food-contact standards, and be opaque, sealed against contamination and easy to clean. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Deionized Water (DI water) is water with nearly all dissolved mineral ions removed by ion exchange, giving a resistivity up to 18 megohm-cm. It is used in electronics and semiconductor manufacturing, laboratories, pharmaceuticals, cosmetics, battery and coolant mixing, and final rinse of plated or painted parts. High-purity water readily picks up ions from metals, so clean polyethylene or polypropylene tanks are preferred. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Reverse Osmosis Water (RO water) is purified by pushing water through semi-permeable membranes, typically removing 95% to 99% of dissolved salts. RO permeate is used for drinking water systems, food and beverage production, car washes, boiler feed, hydroponics, aquariums and laboratories. Because RO water is slightly aggressive toward metals, food-grade plastic storage tanks are common. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Wines are fermented fruit beverages, usually 9% to 15% alcohol by volume, with a pH of about 3 to 4 from tartaric and malic acids and added sulfites as preservatives. Wineries use tanks for fermentation, settling, blending, aging and bottling preparation. Wine storage requires food-grade materials that impart no taste or odor, plus tight lids to limit oxygen exposure. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Xylene (dimethylbenzene, C₈H₁₀, CAS 1330-20-7) is a mixture of ortho-, meta- and para-xylene and ethylbenzene. It is a clear, flammable aromatic solvent with a specific gravity of about 0.86, a boiling point of 279°F to 291°F (137°C to 144°C) and a flash point near 81°F (27°C). Xylene is used in paints, coatings, pesticide formulations, cleaners and degreasers, and para-xylene is the feedstock for PET plastic. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Zinc Chloride (ZnCl₂, CAS 7646-85-7) is a white, highly soluble salt (solid density about 2.9) usually stored as a dense, acidic solution of up to about 2.0 specific gravity. It is corrosive and toxic to aquatic life. Zinc chloride is used as a flux for galvanizing and soldering, in dry-cell batteries, textile processing, wood preservation, oil refining and as a dehydrating agent. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.

Zinc Sulfate (ZnSO₄, CAS 7733-02-0) solution is a clear, mildly acidic liquid with a specific gravity of about 1.18 for this entry. It is used as a micronutrient fertilizer and animal feed supplement, in rayon production, electrogalvanizing, mineral flotation, and as a coagulant and corrosion inhibitor in water treatment. Zinc sulfate solutions are mildly corrosive to steel and galvanized metal. Use the compatibility ratings to choose the right tank resin, fittings and gaskets.