Technical Reference
Technical Specifications
| Parameter | Detail |
|---|---|
| Chemical Name | Sodium Tolyltriazole |
| IUPAC Name | Sodium 4-methyl-1H-benzotriazol-1-ide (and 5-methyl isomer) |
| Common Names | Sodium TTA; NaTTA; Tolyltriazole sodium salt; Methyl benzotriazole sodium salt |
| Molecular Formula | C₇H₆N₃Na (MW 155.14 g/mol) |
| CAS Number | 64665-57-2 (mixture of 4- and 5-methyl isomers) |
| Concentration / Grade | 50% w/w aqueous solution, technical grade |
| Physical State | Liquid |
| Appearance | Clear to pale amber liquid |
| Density | Approximately 1.14–1.16 g/mL at 20°C |
| pH (as supplied, 50% solution) | 8.5–10.5 |
| Solubility in Water | Fully miscible in all proportions |
| Flash Point | None (aqueous solution; non-flammable) |
| UN Number | Not classified as a Dangerous Good for transport in aqueous solution form at 50% concentration under the ADG Code (verify with current SDS prior to transport) |
| ADG Class | Not subject to ADG Code at this concentration; confirm via current SDS and consult your transport provider for loads exceeding bulk quantities |
Applications & Use Cases
- Cooling tower water treatment: Protection of copper, brass, and bronze heat exchanger tubes, condenser heads, and distribution pipework against corrosion and pitting in open evaporative cooling systems
- Closed-loop HVAC and chilled water systems: Ongoing corrosion inhibition of non-ferrous metals in recirculating hot and cold water circuits in commercial and industrial buildings
- Boiler feedwater and condensate return systems: Prevention of copper alloy corrosion in economisers, condensers, and steam condensate pipework
- Industrial process cooling water: Copper and brass protection in heat exchangers serving manufacturing equipment, compressors, and refineries
- Oil and gas produced water and injection systems: Corrosion inhibition of non-ferrous downhole and surface equipment
- Glycol-based antifreeze and heat transfer fluid formulation: Blended as a metal deactivator and corrosion inhibitor in ethylene glycol and propylene glycol systems
- Industrial water treatment formulations: Active component in multi-functional corrosion inhibitor and scale inhibitor concentrates supplied to industry
- Mining and mineral processing water circuits: Non-ferrous metal protection in process water and mine water treatment systems across Queensland, WA, and NSW operations
- Power generation cooling water: Protection of condenser and auxiliary cooling water systems at coal, gas, and renewable energy installations
Dosing Rates & Guidelines
Dosing rates below are indicative based on standard Australian industry practice. Site-specific conditions — including cycles of concentration, makeup water quality, pH, temperature, and system metallurgy — must be assessed before finalising a treatment programme. Always conduct jar testing or consult a qualified water treatment chemist for new applications.
| Application | Initial / Shock Dose | Maintenance Dose | Units | Target Residual (as TTA) | Notes |
|---|---|---|---|---|---|
| Open evaporative cooling tower (system commissioning) | 20–40 | 2–5 | mg/L active TTA in system water | 2–5 mg/L | Shock dose applied at start-up or after system drain-and-refill; maintain residual via bleed-and-feed or continuous dosing pump. At 50% solution, 1 mg/L active TTA ≈ 2 mg/L of product per litre of system volume |
| Open evaporative cooling tower (ongoing maintenance) | — | 2–5 | mg/L active TTA in circulating water | 2–5 mg/L | Monitor via colorimetric TTA test kit or HPLC. Dose frequency determined by blowdown rate and cycles of concentration |
| Closed-loop HVAC / chilled water system | 50–100 | 10–20 | mg/L active TTA in system water | 10–20 mg/L | Higher target residual justified in closed loops due to limited dilution; top up quarterly or as monitoring indicates. Systems with mixed metallurgy (copper and mild steel) require compatibility assessment with other inhibitors |
| Glycol heat transfer fluid (ethylene or propylene glycol) | 500–1,000 | 200–500 | mg/L active TTA in glycol mixture | 200–500 mg/L | Higher dose required due to dilution into glycol matrix and elevated operating temperatures; check compatibility with other glycol inhibitor components |
| Boiler feedwater / condensate return (copper alloy protection) | 5–10 | 1–3 | mg/L active TTA | 1–3 mg/L | Coordinate dosing with oxygen scavenger and filming amine programme; verify compatibility with boiler chemistry. Suitable for low- to medium-pressure boiler systems |
| Industrial process cooling water (once-through or recirculating) | 10–20 | 2–10 | mg/L active TTA | 2–10 mg/L | Target residual depends on severity of corrosion risk and system temperature; higher residuals required above 50°C |
| Corrosion inhibitor concentrate formulation (blending) | — | 1–5% v/v of 50% NaTTA solution | % v/v in formulated product | As per formulation design | For use by registered chemical formulators; ensure compatibility testing with other actives (phosphonates, molybdate, zinc, azoles) prior to bulk production |
Dilution Instructions
Sodium Tolyltriazole 50% solution is water-miscible and does not require hazardous dilution procedures. However, as with all industrial chemicals, correct handling practices must be followed to protect personnel and ensure product efficacy.
- Don appropriate PPE before handling: chemical-resistant gloves (nitrile minimum 0.4 mm thickness), safety glasses or face shield, and chemical-resistant apron. See Safety & Handling section below.
- Confirm the dilution target: Determine the required active TTA concentration in the final system volume (refer to Dosing Rates table above). For a 50% w/w solution, every 1 litre of product contains approximately 570 g of active tolyltriazole. Calculate the volume of product required accordingly.
- Prepare a clean dosing vessel: Use a polyethylene (HDPE) or polypropylene container. Do not use mild steel, copper, or galvanised containers.
- Add the required volume of clean, potable or process water to the dosing vessel first. This dilutes any splashes of concentrate. NaTTA solution is alkaline — there is no violent exotherm on dilution with water, however good practice remains to add product to water, not water to concentrate.
- Slowly add the measured volume of Sodium Tolyltriazole 50% solution to the water whilst stirring gently. Avoid generating aerosols or vigorous splashing.
- Mix thoroughly until a uniform solution is achieved. The solution will remain clear to pale amber.
- Introduce the diluted solution to the system via the designated chemical injection point — preferably downstream of the pump discharge and upstream of the heat exchanger. For cooling towers, dose into the sump or the return water line, avoiding direct spray onto cooling fill or drift eliminators.
- Where using a dosing pump: Use chemical-resistant pump heads (PVDF, polypropylene, or 316 stainless steel wetted parts). Peristaltic pumps with EPDM or Viton tubing are suitable for 50% concentration. Diaphragm metering pumps with Teflon diaphragms are preferred for precision dosing in industrial applications.
- Verify residual after dosing using an approved TTA colorimetric test kit or send a water sample for laboratory analysis. Adjust dosing rate as required.
Chemical Compatibility
Compatible with:
- Phosphonate-based scale and corrosion inhibitors (HEDP, PBTC, ATMP) — commonly co-formulated
- Molybdate-based corrosion inhibitors at typical treatment concentrations
- Benzotriazole (BTA) — compatible and synergistic; NaTTA and BTA are often used together for broadened metal protection
- Polycarboxylate and polyacrylate dispersants used in cooling water treatment
- Ethylene glycol and propylene glycol (fully miscible; widely used in antifreeze formulations)
- Biocides commonly used in cooling towers: isothiazolone blends (e.g. BIT/CMIT/MIT), glutaraldehyde, DBNPA, quaternary ammonium compounds — compatibility confirmed at typical use concentrations; always jar test when introducing new biocide combinations
- Alkaline and neutral pH water treatment programmes (pH 7.0–10.5)
- HDPE, polypropylene, PVC, PVDF, and 316 stainless steel containers and pipework
Incompatible with / Do NOT mix with:
- Strong acids (e.g. hydrochloric acid, sulphuric acid, nitric acid): Protonation of the sodium salt occurs, potentially precipitating the free tolyltriazole acid form; also risk of violent reaction or heat generation. Never blend with acid descalers without thorough compatibility testing.
- Concentrated oxidising biocides (chlorine gas, sodium hypochlorite >10%, bromine concentrates, hydrogen peroxide >30%): Direct mixing in concentrate form can result in degradation of the triazole ring, forming unwanted by-products and loss of inhibitor efficacy. In operational cooling tower water where both are dosed at normal treatment concentrations, exposure occurs but is managed; however, do not blend concentrates together in a dosing vessel.
- Concentrated chlorinated isocyanurate products: Risk of oxidative degradation of NaTTA; dose separately and allow system dilution between additions.
- Heavy metal salts at high concentrations (e.g. zinc sulphate, copper sulphate): May form coordination complexes that reduce inhibitor bioavailability; jar test before blending in formulations.
- Mild steel, copper, galvanised iron, or aluminium containers: Not suitable for long-term storage of the 50% solution.
Safety & Handling
Personal Protective Equipment (PPE):
- Gloves: Chemical-resistant nitrile gloves (minimum 0.4 mm thickness) or neoprene gloves. Replace immediately if contaminated. Latex gloves are not adequate.
- Eye / face protection: Safety glasses with side shields as minimum; full face shield recommended when decanting or handling bulk quantities. Chemical splash goggles required where splash risk is elevated.
- Respiratory protection: Not required under normal handling conditions in well-ventilated areas. Where misting or aerosol generation is possible (e.g. pressure transfer operations), use a half-face respirator fitted with an organic vapour/P2 combination cartridge.
- Body protection: Chemical-resistant apron (polyethylene or PVC) for decanting and dosing operations. For prolonged exposure or bulk handling, chemical-resistant coveralls are recommended.
- Footwear: Chemical-resistant safety boots; avoid open-toed footwear in any chemical handling area.
Storage Requirements:
- Store in original sealed HDPE containers in a cool, dry, well-ventilated area away from direct sunlight and heat sources
- Recommended storage temperature: 5°C to 35°C. Protect from freezing; if frozen, thaw slowly and mix before use — product quality is not permanently affected by a single freeze-thaw cycle provided the container integrity is maintained
- Segregate from strong acids, strong oxidising agents, and chlorine


