Calcium Hypochlorite

Calcium Hypochlorite 45%, 60%, 65% and 70%

Calcium hypochlorite is a solid chlorine-releasing oxidizer and disinfectant used in water treatment, industrial sanitation, swimming pools, wastewater treatment and bleaching processes. Identified by CAS number 7778-54-3, it is available with 45%, 60%, 65% or 70% minimum available chlorine to meet different technical, regulatory and commercial requirements.

The four grades differ primarily in available-chlorine concentration. They may also differ in production process, moisture, water-insoluble matter, residual salts, bulk density, particle size, stability and transport classification. Buyers should therefore compare the complete specification rather than selecting a product by chlorine percentage alone.

• Product name: Calcium Hypochlorite

• Common name: Cal Hypo

• CAS number: 7778-54-3

• EC number: 231-908-7

• Molecular formula: Ca(ClO)₂

• Molecular weight: 142.98 g/mol

• Available-chlorine grades: 45%, 60%, 65% and 70%

• Available forms: Powder, granules and tablets

• Main functions: Disinfectant, oxidizing agent, sanitizer and bleaching agent

• Common packaging: Drums, pails or other approved packaging according to grade

This product is intended for professional and industrial use. The applicable product label, Safety Data Sheet, local regulations and site procedures must be followed.

Which Calcium Hypochlorite Grade Should You Choose?

The right calcium hypochlorite grade depends on the required chlorine output, application, treatment equipment, impurity limits, product registration, packaging and delivered cost per unit of available chlorine.

A higher grade provides more theoretical available chlorine per kilogram. It does not automatically mean that the product is better for every application.

Calcium Hypochlorite Grade Options

Calcium Hypochlorite 45%

Calcium hypochlorite 45% is a lower-strength commercial chlorine product selected for cost-sensitive bleaching, sanitation and suitable water-treatment applications. It may be marketed in some regions as concentrated bleaching powder or chlorinated lime.

The 45% figure refers to minimum available chlorine, not necessarily 45% chemical purity. Buyers should verify moisture, water-insoluble matter, calcium chloride, calcium hydroxide and the intended-use approvals.

Common forms include powder and granules.

Calcium Hypochlorite 60%

Calcium hypochlorite 60% provides a balance between available-chlorine strength and commercial cost. It is used in municipal and industrial water treatment, wastewater disinfection, sanitation, pulp and paper processing, and textile bleaching where the selected grade is approved.

Both hydrated and other commercial formulations may be sold at approximately 60% available chlorine. The moisture specification and transport classification should therefore be confirmed from the actual TDS and SDS.

Common forms include powder, granules and tablets.

Calcium Hypochlorite 65%

Calcium hypochlorite 65% is a widely specified high-strength grade for water-treatment plants, swimming pools, industrial sanitation, wastewater treatment and bleaching applications.

It may be produced through different manufacturing routes. Buyers should not assume that every 65% product has the same solubility, moisture, insoluble matter or storage stability.

Common forms include free-flowing granules, powder and tablets.

Calcium Hypochlorite 70%

Calcium hypochlorite 70% is a high-strength grade commonly selected when buyers require greater available-chlorine concentration, consistent granular form and efficient international transportation.

It is widely used in swimming pools, municipal water treatment, industrial water systems and sanitation programs where the product has the required registration or approval.

Common forms include granules and tablets. Moisture, particle size, insoluble matter and transport classification should be defined in the purchasing specification.

Commercial Quality Specification

Specifications may vary according to production process, hydration, particle size and packaging. The agreed Technical Data Sheet and lot-specific Certificate of Analysis govern the delivered product.

Additional quality parameters may include:

• Calcium hydroxide

• Calcium chloride

• Sodium chloride

• Calcium chlorate

• Bulk density

• Granule-size distribution

• Storage-stability loss

• pH of a specified solution

• Heavy metals or application-specific impurities

When these parameters affect the intended process, include numerical limits and required test methods in the inquiry.

What Does Available Chlorine Mean?

Available chlorine expresses the oxidizing capacity of a chlorine-containing product as an equivalent amount of elemental chlorine. It is a performance measurement and is not the same as calcium hypochlorite assay or chemical purity.

For equal product weight:

• A 45% grade provides at least 0.45 kg of theoretical available chlorine per kilogram.

• A 60% grade provides at least 0.60 kg.

• A 65% grade provides at least 0.65 kg.

• A 70% grade provides at least 0.70 kg.

Actual application dosage must account for chlorine demand, water chemistry, storage age, target residual, contact time and local treatment requirements. Dosage should be determined by qualified personnel rather than from the percentage alone.

Is 45% Calcium Hypochlorite Lower Quality?

Not necessarily. A 45% product has a lower available-chlorine concentration, but it may be suitable for an application that does not require a high-strength grade.

Quality should be evaluated using the complete specification, including:

• Whether the available chlorine meets the guaranteed minimum

• Moisture and insoluble-matter limits

• Particle uniformity

• Storage stability

• Packaging integrity

• Batch consistency

• Suitability for the intended use

• Cost per unit of available chlorine

• Applicable regulatory approvals

A compliant 45% grade may be more appropriate than a 70% grade for some industrial bleaching or cost-sensitive processes.

Granules, Powder or Tablets

Granular Calcium Hypochlorite

Granular material is commonly selected for industrial water treatment, pool products, wastewater treatment and controlled dissolution systems. Particle-size distribution affects flow, dust generation, dissolution and feeder compatibility.

Specify the required mesh or particle-size range when it is important to the equipment.

Calcium Hypochlorite Powder

Powder grades are commonly used in bleaching, sanitation and manual solution-preparation processes. In international trade, the word “powder” may also describe relatively fine granules.

For consistent procurement, define particle size numerically instead of relying only on the word “powder.”

Calcium Hypochlorite Tablets

Tablets are used with compatible feeders and in selected pool, wastewater and sanitation systems. Available options can differ in tablet weight, diameter, thickness, dissolution rate and formulation.

Only use tablets in equipment expressly designed and approved for that calcium hypochlorite product.

Calcium-Process vs. Sodium-Process Calcium Hypochlorite

Commercial calcium hypochlorite can be manufactured through calcium-process or sodium-process routes. The production route may influence available chlorine, residual salts, moisture, insoluble matter, granule density and storage characteristics.

Calcium-Process Product

Calcium-process material is often associated with 45%, 60% and some 65% commercial grades. However, available chlorine alone cannot confirm how a product was manufactured.

Important parameters may include calcium chloride, calcium hydroxide, moisture, insoluble matter and storage stability.

Sodium-Process Product

Sodium-process material is commonly associated with 65% and 70% products and may offer a denser or more uniform granular form. Relevant parameters can include sodium chloride, moisture, insoluble matter, bulk density and particle-size distribution.

Do not describe a grade as sodium process or calcium process unless the manufacturer’s documentation confirms the production route.

How Does Calcium Hypochlorite Disinfect Water?

When introduced into water, calcium hypochlorite releases hypochlorite species. Depending on the water pH, part of the available chlorine is present as hypochlorous acid, an active oxidizing and disinfecting species.

Performance depends on:

• Water pH

• Temperature

• Organic and inorganic chlorine demand

• Contact time

• Mixing

• Product condition

• Target free-chlorine residual

• Treatment-system design

This page does not provide application dosage. Treatment levels must be established through site-specific testing, the approved product label and applicable water-quality regulations.

Calcium Hypochlorite Applications

Municipal and Drinking-Water Treatment

Approved calcium hypochlorite grades can provide a solid chlorine source for municipal water plants, small-community systems and emergency or decentralized treatment programs.

A product should only be marketed or used for drinking water when its grade, impurities, certification and registration meet the requirements of the destination market.

Swimming Pools and Spas

Calcium hypochlorite is widely used in registered pool-chlorination and shock-treatment products. It provides available chlorine without inherently adding cyanuric acid.

Because the product introduces calcium, operators should monitor calcium hardness and the overall water balance.

Wastewater Treatment

Cal hypo may be used for final disinfection, selected oxidation processes and odor-control programs in municipal or industrial wastewater treatment.

Product grade, dissolution method and dosage should be selected according to wastewater quality, chlorine demand and discharge requirements.

Industrial Water and Cooling Systems

Industrial facilities may use calcium hypochlorite as a chlorine source for cooling water, process water and other managed water systems.

The treatment program should consider calcium contribution, scaling potential, material compatibility and monitoring requirements.

Textile and Pulp Bleaching

The 45%, 60% and other suitable grades may be used as oxidizing or bleaching agents in textile, pulp and paper processes. Required concentration and impurity limits depend on the raw material and finished-product quality.

Industrial and Institutional Sanitation

Calcium hypochlorite may support professionally managed sanitation programs where permitted. The selected grade must be compatible with the required chlorine concentration, contact time and local biocidal regulations.

Calcium Hypochlorite vs. Sodium Hypochlorite and TCCA

These products must not be mixed. Calcium hypochlorite must be stored separately from TCCA, dichlor, sodium hypochlorite and other incompatible treatment chemicals.

Packaging Options

Typical packaging options may include approved plastic drums, iron drums, compound-fiber drums or pails with moisture-resistant inner packaging.

Common international net weights include:

• 15 kg

• 25 kg

• 40 kg

• 45 kg

• 50 kg

Packaging availability depends on grade, product form, transport classification and destination. State any private-label, neutral-label, language or palletization requirements when requesting a quotation.

Storage and Safe Handling

Calcium hypochlorite is a strong oxidizer. Heat, contamination, moisture and incompatible chemicals can cause accelerated decomposition, fire or the release of hazardous chlorine-containing gases.

Store the product:

• In its original closed and approved packaging

• In a cool, dry and ventilated place

• Protected from sunlight, heat and moisture

• Away from acids and ammonia

• Away from oils, organic materials and combustible substances

• Away from reducing agents

• Away from other chlorinating products

• According to the current SDS and local regulations

Never mix calcium hypochlorite with acids, ammonia, organic chemicals, TCCA, dichlor or other pool chemicals. Only trained personnel should handle damaged packages or contaminated material according to an approved emergency procedure.

Calcium Hypochlorite UN Number and Transport Classification

The correct UN number is determined by the product’s moisture, hydration, composition and corrosive properties—not by the 45%, 60%, 65% or 70% available-chlorine value alone.

Common transport entries include:

• UN1748 for applicable dry calcium hypochlorite or dry mixtures containing more than 39% available chlorine

• UN2880 for applicable hydrated calcium hypochlorite containing 5.5%–16% water

• Other calcium hypochlorite entries where an additional corrosive classification applies

• Class 5.1 for oxidizing substances, with the final packing group and subsidiary hazard determined by the product

Use the exact shipping name, UN number, hazard class, packing group and packaging instructions stated in the current SDS and dangerous-goods declaration.

Documents to Request from the Supplier

A calcium hypochlorite supplier-qualification package may include:

• Technical Data Sheet

• Current Safety Data Sheet

• Lot-specific Certificate of Analysis

• Available-chlorine result

• Moisture result

• Water-insoluble-matter result

• Particle-size analysis

• Packaging specification

• Dangerous-goods declaration

• Country-of-origin statement

• Product-registration documents

• Potable-water or biocidal certification, when applicable

• Third-party inspection report, when required

Confirm that all documentation applies to the selected 45%, 60%, 65% or 70% grade rather than to another product in the supplier’s range.

Request a Calcium Hypochlorite Quote

For an accurate quotation, provide:

• Required grade: 45%, 60%, 65% or 70%

• Required available-chlorine minimum

• Production process, if specified

• Form: Powder, granules or tablets

• Particle-size or tablet-size requirement

• Moisture and insoluble-matter limits

• Packaging and net weight

• Quantity per order

• Estimated annual demand

• Delivery country and port

• Intended application

• Required certifications and documents

• Private-label requirements

• Target delivery date

Send us your calcium hypochlorite specification to receive the appropriate product option, packaging information, documentation, lead time and commercial quotation.

Frequently Asked Questions About Calcium Hypochlorite

What grades of calcium hypochlorite are available?

The available grades are 45%, 60%, 65% and 70% minimum available chlorine. Product forms and specifications may differ by grade.

Which calcium hypochlorite grade is best?

There is no universally best grade. The correct choice depends on chlorine demand, application, equipment, impurities, regulations, packaging and cost per unit of available chlorine.

What is the difference between 45% and 70% calcium hypochlorite?

The primary difference is available-chlorine concentration. A 70% grade supplies more theoretical chlorine per kilogram, while a 45% grade may offer a more economical option for suitable industrial applications.

Is available chlorine the same as calcium hypochlorite purity?

No. Available chlorine measures oxidizing capacity. It should not be presented as an identical measurement of chemical assay or calcium hypochlorite purity.

Is 60% calcium hypochlorite suitable for water treatment?

It may be suitable when the product grade, impurity profile, certification and treatment process meet applicable water-treatment requirements. Confirm the intended-use documentation before purchase.

Are 65% and 70% grades always made by the sodium process?

No. Although high-strength products are often associated with the sodium process, the percentage alone does not prove the manufacturing route. Request confirmation from the manufacturer.

Is calcium hypochlorite stabilized chlorine?

Pure calcium hypochlorite does not inherently contain cyanuric acid and is generally considered unstabilized chlorine. Formulated products may contain other ingredients, so check the label.

Does calcium hypochlorite increase water hardness?

Yes. It introduces calcium ions and can increase calcium hardness, which should be considered in pools and scale-sensitive systems.

What is the UN number for calcium hypochlorite?

The number is product-specific. Applicable dry products may use UN1748, while qualifying hydrated products may use UN2880. The supplier’s current SDS must determine the final classification.

How should the four grades be compared?

Compare available chlorine, moisture, insoluble matter, particle size, production route, packaging, transport classification, documentation and delivered cost per unit of available chlorine.

What information is needed for a bulk quote?

Provide the required grade, form, particle size, packaging, order quantity, destination, intended application and required certifications or documents.