Hybrid nanomaterial from pyrolyzed biomass and Fe3O4 magnetic nanoparticles for the adsorption of textile dyes

Industrial dyes are harmful compounds often present in wastewater. In this work, a magnetic nanohybrid material (HB) was hydrothermally synthesized from pyrolyzed sugarcane straw (CN) and magnetic iron oxide nanoparticles. The material was characterized by XRD, FTIR, SEM, TGA, and PZC, and tested for the adsorptive removal of congo red (CR) and indigo carmine (IC) dyes from aqueous solutions at pH 7.0 and 10.0, respectively. The kinetics of adsorption was well explained by both the pseudo-second order (PSO) model ( R-adj(2) similar to 0.99 for CR, 0.96 for IC) and the Elovich model ( R-adj(2) similar to 0.98 for CR, 0.98 for IC). After 24 h, the maximum adsorption capacities of the material were similar to 18.39 mg g(-1) for CR and similar to 1.46 mg g(-1) for IC. Adsorption isotherms were obtained at 25, 35, and 45 degrees C, and four different models were tested. The Sips model, which combines Langmuir and Freundlich, was used to fit the data. HB exhibited greater performance removing CR dye (%R similar to 72%) than IC (%R similar to 27%), therefore suggesting great potential as an adsorbent for CR from wastewater.

Automated summary

In this study, a magnetic nanohybrid material was synthesized and used to remove congo red and indigo carmine dyes from aqueous solutions. The material showed good adsorption capacity and kinetics, suggesting its potential for wastewater treatment.