Sodium Thiosulfate Pentahydrate

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Sodium Thiosulfate Pentahydrate

Ballast Tank Chem Sodium Thiosulfate Pentahydrate
Express Kolkata & Haldia Port 2-4 Hr Berth Delivery
Ballast Tank Chem
Part No. / SKU: RXSOL-23-2031-025

Sodium Thiosulfate for Ballast Water Neutralization, can be dosed into the treated ballast water to reduce residual oxidizing compounds.

Available Packaging:
Powder form can be customized in 250, 500 Gram to 1, 5, 10, 20, 50 Kg Available in Kandla, Mundra, Mumbai, Manglore, Chennai, Visakhapatnam, Kolkata, Fujairah, Dubai - Middle East
Ready Port Stock 25L, 210L Drums & 1000L IBC
IMPA / ISSA Standard MARPOL Compliant Formulations
ISO 9001:2015 QA TDS, MSDS & COA Available

Application & Uses

Why Is Sodium Thiosulfate Required in Ballast Water Treatment?

 

Many marine ballast water treatment systems use electro-chlorination or other oxidizing technologies to control aquatic organisms and microorganisms in ballast water.

These systems generate or introduce oxidizing agents that provide disinfection during ballast water treatment.

However, residual oxidants remaining in the treated ballast water may require neutralization before discharge.

Sodium Thiosulfate Pentahydrate acts as a reducing agent, helping convert residual chlorine and suitable oxidants into less reactive compounds.

This process is known as ballast water dechlorination or neutralization.

The required neutralization procedure depends on the BWMS manufacturer's instructions, the oxidant concentration and the vessel's approved operating procedures.

 

Typical Applications

Sodium Thiosulfate Anhydrous can be used for:

  • Ballast water dechlorination

  • Residual chlorine neutralization

  • Electrochlorination BWMS

  • Sodium hypochlorite-treated ballast water

  • Oxidizing biocide neutralization

  • Ballast water discharge preparation

  • Marine water-treatment systems

How Sodium Thiosulfate Works

Sodium thiosulfate functions as a reducing agent. It reacts with residual oxidizing species and converts them into less oxidizing chemical species.

In a chlorine-treated ballast water system, sodium thiosulfate can consume residual chlorine, helping reduce the Total Residual Oxidant (TRO) concentration before discharge.

The required dosage depends on:

  • Initial TRO concentration

  • Ballast water volume

  • BWMS technology

  • Water chemistry

  • Required discharge residual

  • Chemical concentration

  • Reaction/contact time

  • Dosing-system configuration

Therefore, dosing should be calculated based on the actual BWMS operating parameters rather than using a universal fixed dosage.

Dosage & Directions for Use

Illustrative Dosage Calculation

For complete oxidation of thiosulfate to sulfate by chlorine, the theoretical chemical demand is approximately:

0.875 mg of pure Sodium Thiosulfate Pentahydrate per 1 mg of chlorine expressed as Cl₂ equivalent.

For example, with 1,000 m³ of ballast water containing 2 mg/L residual oxidant expressed as Cl₂:

Parameter

Value

Ballast Water Volume

1,000 m³

TRO Concentration

2 mg/L as Cl₂

Theoretical Pure Chemical Requirement

Approximately 1.75 kg

Chemical Purity

99%

Purity-Adjusted Theoretical Requirement

Approximately 1.77 kg

Important: This is an illustrative chemical stoichiometry calculation, not a recommended shipboard dosage. Thiosulfate may follow different reaction pathways, and actual demand can differ substantially. The approved BWMS neutralization chemical, dosing algorithm and TRO feedback controls must govern practical use.

Important Dosing Consideration

The required quantity of Sodium Thiosulfate should be determined from the actual TRO measurement and BWMS dosing requirements. Overdosing or underdosing can affect ballast-water treatment performance and discharge conditions.

For shipboard operation, dosing should therefore be controlled through the vessel's approved BWMS procedures, TRO monitoring system, and chemical-dosing equipment.

Sodium Thiosulfate for Ballast Water Neutralization

Many Ballast Water Management Systems (BWMS) use an oxidizing treatment process to control organisms in ballast water. Depending on the technology, treatment may generate or introduce free chlorine, hypochlorite, or other oxidizing residuals.

Before discharge, residual oxidant may need to be neutralized.

Sodium Thiosulfate Anhydrous can be dosed into the treated ballast water to reduce residual oxidizing compounds.

This makes it an important chemical for selected ballast-water neutralization systems.

Technical Specifications & Properties

Technical Specifications

Property

Typical Information

Product Name

Sodium Thiosulfate Pentahydrate

Brand

RXSOL

Chemical Formula

Na₂S₂O₃·5H₂O

CAS Number

10102-17-7

Molecular Weight

248.18 g/mol

Appearance

White or colourless crystalline solid

Purity

Typically 98–99% or higher, depending on grade

Solubility

Highly soluble in water

Chemical Function

Reducing agent / chlorine neutralizer

Marine Application

Ballast water residual oxidant neutralization

Product Form

Crystalline solid

Packing

Commonly 25 kg bags, subject to availability

Specifications are indicative and should be confirmed against the supplied batch COA.

Recommended Industrial & Shipboard Areas

Key Benefits of RXSOL Sodium Thiosulfate Pentahydrate

  • Effective reducing agent for residual chlorine neutralization

  • Suitable for compatible oxidant-based ballast water treatment systems

  • Highly soluble in water

  • Can be prepared as an aqueous chemical dosing solution

  • Helps reduce Total Residual Oxidant (TRO) concentrations

  • Supports controlled ballast water discharge procedures

  • Suitable for industrial and marine water treatment applications

  • Convenient crystalline form for storage and chemical solution preparation

Product Description & Chemical Profile

Sodium Thiosulfate Pentahydrate for Ballast Water Treatment – Marine Chemical Supplier | RXSOL DUBI CHEM

Sodium Thiosulfate Pentahydrate – Chlorine Neutralizer for Marine Ballast Water Management Systems (BWMS)

RXSOL Sodium Thiosulfate Pentahydrate is a water-soluble reducing agent used for the neutralization of residual chlorine and other suitable oxidizing disinfectants in marine ballast water treatment applications.

DUBI CHEM RXSOL supplies marine chemicals, ballast water treatment chemicals and industrial water treatment products to shipping companies, ship chandlers, vessel operators and marine engineering companies across the UAE, Oman, Saudi Arabia, Qatar, Bahrain, Kuwait and India.

 

Sodium Thiosulfate Pentahydrate is particularly relevant to electro-chlorination and other oxidant-based Ballast Water Management Systems (BWMS) where residual oxidants must be neutralized before treated ballast water is discharged.

Sodium Thiosulfate commonly used in Dechlorination of municipal wastewater, pulp & paper, power, and textile water treatment plants and as an Oxygen scavenger in oil well drilling process in Mining industries. Also chemically suitable for Aluminium cation reaction.

Sodium Thiosulfate used as a Pond / Aquarium Dechlorinator.  But Sodium Thiosulfate does not treat for Chloramine, only Chlorine. Chloramine is a chemical compound composed of chlorine and ammonia and more and more utilities are converting to its use. Check with your municipal water company to learn which chemical they are using. If Chloramine is the disinfectant, please research other knowledgeable sources to learn your best solution for water treatment.

Molecular Formula  ::: Na2S2O3 - 5H2O

This product also used as a Photography as a fixing agent (hypo) to dissolve unchanged silver salts from exposed negatives.

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