sustainable, PAH-free binderS for ramming pastes

Ramming paste — produced from carbon aggregate mixed with a liquid binder — is used to seal cathode blocks in aluminium electrolysis pots. It plays a crucial role in pot integrity and performance, and the binder is a key component.

Traditionally, coal tar pitch has been used as a binder, but it contains polycyclic aromatic hydrocarbons (PAHs), which pose significant health, safety, and environmental challenges.

Borregaard offers a sustainable alternative to traditional binders: bio-based lignosulfonates, derived from lignin — a natural, carbon-rich component of wood.

Proven performance

Pilot-scale tests conducted with R&D Carbon showed that Borregaard lignosulfonates deliver:

  • Comparable or better green and baked paste properties than coal tar pitch
  • Excellent density, strength and conductivity
  • Performance within typical industrial ranges for PAH-free ramming pastes

Easy to handle and customise

Our lignosulfonates are:

  • Supplied as dry powders for easy storage and handling
  • Dissolved in water and other solvents to create flexible binder formulations
  • Adjustable in viscosity and coking value to suit different aggregate types

Safe, renewable, and industrially available

  • 100 % bio-based and ISCC PLUS certified biocircular raw material
  • Non-hazardous and PAH-free, improving workplace safety
  • Produced at Borregaard’s biorefinery from sustainable wood raw materials

The result

A safe, high-performance, and environmentally responsible solution for modern ramming paste production.

Get in touch to learn more!

Get in touch to learn more!