Cradle to Gate
Identity ID
454b5edf-fcf5-4b9c-94e5-8de402a75787
Materials
Associated ID
c5689d7d-f2ca-446c-92c3-f78b402c3669
Included activities starts
Included activities ends
Description
Sodium hydroxide is an important chemical raw material widely used in industry, medicine, and daily life. This dataset models sodium hydroxide as a pure substance and includes main raw and auxiliary materials, energy use, atmospheric emissions, and waste from the production process. Infrastructure such as manufacturing of production equipment and construction of facilities is not included within the system boundary of the dataset. The life cycle inventory is compiled from multiple data sources. Chlorine and hydrogen are co-products of this process. Allocation follows the method specified in the relevant PCR (Eurochlor, 2022): physical allocation based on stoichiometry is applied to raw salt, and chlorine emissions are allocated solely to the chlorine process. Electricity and steam All other inputs and outputs are allocated by mass to all co-products; the ion-exchange membrane process for caustic soda production includes salt dissolution, primary purification, secondary purification, electrolysis, and dilute brine dechlorination steps.
Activity Description
The ion-exchange membrane process for caustic soda production includes salt dissolution, primary purification, secondary purification, electrolysis, and dilute brine dechlorination steps. Chlorine and hydrogen are co-produced in this process.
Process Description
Sodium hydroxide, CAS number: 1310-73-2, also known as caustic soda or lye, has the chemical formula NaOH. It is a highly corrosive strong base that is highly soluble in water. Pure solid sodium hydroxide appears as white, while pure liquid caustic soda is a colorless and transparent solution. It is a fundamental chemical raw material widely used in industries such as chemical manufacturing, papermaking, petroleum, and textiles.
Time period
2014
2026
Geography
China
Macroeconomic value
Business-as-Usual
Data validation
Yes
Technology
Current Technology
Technology comment
Raw salt is heated after dissolving and primary/secondary purification, then fed into an ion-exchange membrane electrolyzer. Inside the cell, sodium ions selectively pass through the ion membrane; chlorine (Cl₂) is generated at the anode, while water reacts at the cathode to produce hydroxide ions (OH⁻) and hydrogen gas (H₂). The OH⁻ combines with sodium ions migrating from the anode compartment to form sodium hydroxide.