Sodium Hypochlorite

In water it forms hypochlorous acid (HOCl) and hypochlorite ion (OCl⁻). HOCl, the more biocidal species, penetrates microbial cells and oxidizes enzymes and cell components, inactivating bacteria and viruses. Because the HOCl fraction grows as pH falls, disinfection is generally more efficient near neutral pH than in strongly alkaline water.

Hypochlorite decomposes on storage, and heat, sunlight and traces of metals such as iron, copper and nickel accelerate the loss of available chlorine. The product's shelf life is around 6 months in a cool, dark store. Rotate stock first-in-first-out, buy to match consumption, and base dosing on the measured strength on each batch's certificate of analysis.

Available chlorine expresses the solution's oxidizing and disinfecting capacity as the equivalent amount of elemental chlorine. It is the figure used in dose calculations — a solution at 12% available chlorine delivers roughly twice the disinfecting power per liter of one at 6%. The actual value for each CHIMI ART batch is stated on its certificate of analysis.

Acids — including hydrochloric and sulfuric acid and acidic cleaners — release toxic chlorine gas on contact with hypochlorite, and ammonia or ammonium-based products form toxic chloramine vapors. Store it segregated from both, in vented containers away from heat and sunlight, and never combine cleaning chemicals in the same tank or line.

Routine disinfection typically targets a free chlorine residual of 1-5 mg/L, with 10-20 mg/L applied for shock treatment; the exact requirement depends on organic load, ammonia content, contact time and the applicable standard for your system. Monitor residual chlorine at the compliance point and adjust the feed rate accordingly.

Work in available chlorine. A 12 % w/v solution carries about 120 g of available chlorine per litre, so 1 kg of chlorine equivalent — enough to dose 1,000 m³ at 1 mg/L before any chlorine demand — is roughly 8.3 L of product. Add the water's chlorine demand to the residual you need, multiply by the flow, and divide by the measured available chlorine of the batch in use, not the nominal label strength.

HDPE, PVC, CPVC, PTFE, PVDF, vinyl-ester FRP and titanium. Mild steel, copper, brass, aluminium and most stainless steels are attacked or catalyse decomposition and must be avoided, including in pump internals, fittings and instrumentation. Tanks need vented lids — hypochlorite releases oxygen as it ages — and should be kept out of sunlight and heat.

It is the most widely used drinking-water disinfectant in the world. Water utilities specify the product against their national drinking-water rules — in Europe the product standard is EN 901, which limits chlorate, bromate and heavy metals — and dose to hold a free chlorine residual, with the WHO guideline of at least 0.5 mg/L after 30 minutes' contact at pH below 8. Because chlorate rises as the solution ages, drinking-water users keep stock fresh and dose from the batch assay.

Chlorine gas is the cheapest per kilogram of chlorine but needs pressurised cylinders, scrubbers and trained handling; calcium hypochlorite is a stable solid (around 65–70 % available chlorine) that suits remote sites but adds calcium hardness and needs dissolving; sodium hypochlorite is a liquid that doses directly with a simple metering pump and carries no gas-handling risk, at the cost of a shorter shelf life. Most municipal and industrial plants in Egypt choose liquid hypochlorite for that safety and simplicity.

Yes — 10% available chlorine is the standard strength for municipal drinking-water and industrial disinfection, while 12-15% grades carry more chlorine per delivered litre but lose strength faster in summer heat. We supply the full 10-15% range from fresh local production, so the available chlorine on delivery matches the label, with dosing guidance available for either strength.