Techno‐Economic assessment for superactive carbon production from side stream lignin

Superactive carbon (SAC), having a high surface area of over 2500 m2/g, could be a superior choice for many applications. However, the manufacture of SAC in bulk quantities is challenging. To demonstrate the possibility of SAC manufacturing in large amounts, a techno‐economic assessment was performed. For that purpose, a new method utilizing a mixture of waste lignin, KOH and KCl was employed. The chemicals were recovered after use. The technical assessment was performed based on laboratory‐scale experimental findings, a simplified process diagram, and mass and heat balance calculations. The economic evaluation was assessed through the estimation of capital costs (CAPEX), operational costs (OPEX) and the minimum selling price (MSP). Moreover, to demonstrate the potential costs saving for the water treatment process, the performance of SAC for the removal of natural organic matter was compared with that of commercial active carbon. SAC was obtained at a minimized KOH amount (1 g/g) and chemicals were successfully recovered with a rate of 5–10% losses. The CAPEX, OPEX and MSP were found to be 4–21 million EUR, 1–9 million EUR/year and 4.4–2.9 kEUR/t for a 0.5–5.0 t/year production capacity, respectively, at a profitability requirement of 20% and a less than 5 year payback period. In addition, SAC demonstrated considerably higher adsorptive capacity for natural organic matter (600–900 mg total organic carbon/g) compared with commercial active carbon (40–50 mg total organic carbon/g), which could lead to substantial process savings. SAC manufacture through this method has been validated and the benefit for the potential application is sufficiently clear to promote the successful commercialization of SAC using lignin wastes. © 2022 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.