Production of hydrochars from Pinus caribaea for biosorption of methylene blue and tartrazine yellow dyes

Abstract

Wood is one of the most abundant renewable resources in the world. However, large volumes of waste are generated in the losses and cuts of wood saws, being an important environmental problem. This work aims to evaluate the production of hydrochar from wood residues of Pinus caribaea combined with acid-base treatment for application as dyes Methylene Blue (MB) and Tartrazine Yellow (TAR). Hydrocarbonization was carried out at 200 or 240 ..C for 12 or 24 h, in acidic or basic medium. The pHZPC of the hydrocarbons obtained in acidic medium was between 2.66-4.12 and 4.46-5.76 for those processed in basic medium. The pseudo-secondorder model (PSO) better fitted the adsorption of MB and TAR on Pinus in natura and on hydrochar. In addition, the Sips model was considered the most suitable for MB (qmax= 132.1 mg g-1 for PIN and 149.0 mg g-1 for PIN-200-24-B) and Toth for TAR (qmax= 18.14 mg g-1 for PIN and 23.01 mg g-1 for PIN-200-24-B adsorption isotherms). Therefore, the hydrocarbonization of waste generated from the wood industry in acidic and basic environments has great potential for the treatment of materials such as biosorbents, thus promoting greater sustainability in this sector.