CBk-EX, CBk-RX and CBk-SX Recovered Carbon Black Grades

CBk Carbon Black Products

Klean Carbon CBk-EX, CBk-RX and CBk-SX are new grades of carbon black reinforcing fillers that fully or partially replace the N300, N600 and N700 series of conventional carbon blacks.

The CBk product line exists to remove the main obstacle to recovered carbon black adoption: the absence of a clear, specifiable equivalence to the conventional grades a compounder already buys. Klean Carbon is an ASTM recovered carbon black (rCB) filler produced exclusively by Klean Industries Inc., and the CBk grades are the commercial expression of that material.

The grade family

• Klean Carbon CBk-EX — a recovered carbon black reinforcing filler supplied for full or partial replacement of conventional carbon black grades.
• Klean Carbon CBk-RX — a recovered carbon black reinforcing filler supplied for full or partial replacement of conventional carbon black grades.
• Klean Carbon CBk-SX — a recovered carbon black reinforcing filler supplied for full or partial replacement of conventional carbon black grades.

Collectively the three grades are targeted at the N300 series high-abrasion furnace blacks, the N600 series general-purpose grades, and the N700 series semi-reinforcing grades — the three families that account for the bulk of industrial rubber consumption.

Full or partial replacement

Both routes are legitimate and the choice is a compounding decision, not a marketing one. Partial replacement substitutes a defined share of the conventional black in an existing recipe, which lets a plant capture recycled-content and cost benefit with minimal requalification risk. Full replacement takes the conventional grade out entirely, and is normally approached where the duty cycle and property window allow it. Klean works with customers on both, starting from the incumbent grade and the properties that must hold.

How to qualify a CBk grade

A disciplined evaluation follows the same path every time: identify the incumbent ASTM grade and loading, define the non-negotiable properties, trial partial replacement in the existing cure system, then step the replacement level until a property limit is reached. Processing behaviour — mixing energy, dispersion, extrusion and mould flow — should be logged alongside the physicals, because that is where substitution programmes usually succeed or fail in production rather than in the lab.

Supply, scale and consistency

CBk grades come from plants Klean Industries designs and delivers, with upgrading, milling and pelletising specified as part of the process rather than bolted on afterwards. For customers evaluating larger programmes, that same engineering capability is available as feasibility work, design and engineering, and turn-key delivery.