Bipolar Membrane (BPM)

Industrial-Grade Bipolar Membrane Electrodialysis for Acid-Base Production & Lithium Hydroxide Generation

A bipolar membrane (BPM) is a specialized ion exchange membrane composed of an anion exchange layer (AEL), a cation exchange layer (CEL), and an intermediate catalytic layer. Under the influence of an electric field, bipolar membranes dissociate water molecules into H⁺ and OH⁻ ions, enabling the simultaneous generation of acids and bases. This unique property makes bipolar membrane technology highly advantageous for applications such as lithium hydroxide (LiOH) production and salt-to-acid-base conversion processes.

Haipu supplies a comprehensive range of bipolar membrane products in multiple specifications to meet diverse industrial application requirements, including BPM-100, BPM-200, and BPM-300 series.

Industrial bipolar membrane roll product

Bipolar Membrane Specifications

Bipolar Membrane Type	Model	Dimensions	Thickness (μm)	Burst Strength (MPa)	Operating Temperature (°C)	pH Range	Alkali Concentration (mol/L)	Acid/Base Purity
Bipolar Membrane (BPM)	BPM-100	20×40, 40×80, 55×110 Custom sizes available	150±20	≥0.5	15–40	0–14	2.5	97.5%
	BPM-200	Custom sizes available	150±20	≥0.5	15–40	0–14	3	99%
	BPM-300	Custom sizes available	150±20	≥0.5	15–40	0–14	≥2.5	≥97.5%

Get complete technical data and detailed specifications for all BPM series

📄 Download Bipolar Membrane Datasheet (PDF)

File size: ~2.5 MB | Includes BPM-100 / BPM-200 / BPM-300 full specifications

Key Advantages of Haipu Bipolar Membranes

High Efficiency

Water dissociation operates at low voltage with stable performance and consistent current efficiency throughout the service life, ensuring reliable long-term operation.

Low Energy Consumption

Monolithic bipolar membrane construction delivers low interface resistance, significantly reducing operational energy costs compared to conventional chemical processes.

Long Service Life

Premium materials with interlaced and fused anion-cation interface provide excellent swelling resistance, superior chemical stability, and high mechanical strength.

Green & Sustainable

Reduces chemical reagent consumption and pollutant emissions, converting waste streams into valuable resources and enabling circular economy principles in industrial production.

Bipolar Membrane Electrodialysis System

The bipolar membrane electrodialysis (BMED) system is an innovative and highly efficient integrated system built upon conventional electrodialysis technology. Its core configuration consists of alternating anion exchange membranes, cation exchange membranes, and the critical bipolar membranes.

This revolutionary configuration enables "salt conversion" and "acid-base regeneration" functionality. Without requiring external acid or alkali addition, the system directly converts salt solutions (such as sodium chloride, sodium sulfate, lithium sulfate) into their corresponding acids (e.g., hydrochloric acid, sulfuric acid) and bases (e.g., sodium hydroxide, lithium hydroxide), while simultaneously achieving material separation and concentration.

Bipolar membrane electrodialysis system schematic diagram

Industrial Applications

High-Purity Acid & Alkali Production

The BMED system utilizes acid-alkali resistant anion exchange membranes, cation exchange membranes, and bipolar membranes to produce corresponding inorganic acids and alkalis from inorganic salt feedstocks. Suitable for sodium salt, potassium salt, sulfate, and nitrate systems, including sodium sulfate, potassium nitrate, and various industrial salt streams.

High-Purity Lithium Hydroxide (LiOH) Production

Under a direct current electric field, water is dissociated into H⁺ and OH⁻ ions. The OH⁻ ions migrate through a dedicated lithium-selective membrane and combine with Li⁺ ions from the salt solution (e.g., lithium sulfate) to directly produce high-purity lithium hydroxide solution. The corresponding acid is generated as a valuable by-product, achieving efficient resource recycling in lithium processing.