Black-wattle tannin/kraft lignin H3PO4-activated carbon xerogels as excellent and sustainable adsorbents

Author(s)

de Moraes, Nicolas Perciani ; Boldrin, Flavio Henrique Covolam ; Campos, Tiago Moreira Bastos ; Thim, Gilmar Patrocinio ; Yu, Lianqing ; Lanza, Marcos Roberto de Vasconcelos ; Rodrigues, Liana Alvares

• Document type: Journal article
• Source: International Journal of Biological Macromolecules; v. 227, p. 13-pg., 2022-12-19.

Abstract

This work proposed new black-wattle tannin/kraft lignin H3PO4-activated carbon xerogels as sustainable and efficient adsorbents. The precursors were chosen based on their eco-friendly and cost-effective nature, aiming to achieve adsorbents with high adsorption capacities. Carbon xerogels were synthesized through polycondensation with formaldehyde and alkaline catalyst in a simple one-pot procedure. Activation was performed using H3PO4 in a tubular furnace (500 degrees C), under a nitrogen atmosphere. Results show that the inclusion of the kraft lignin led to changes in the morphology of the materials, facilitating the development of their porous structure and increasing specific surface area and pore volume. The best adsorbent (XLT 50 %) was synthesized using a 1:1 tannin/kraft lignin mass ratio. This material presented an adsorption capacity of nearly 1150 mg g-1 of methylene blue (pH = 5 and T = 298 K), which was linked to its high specific surface area of 1348 m2 g-1. The adsorption process followed the pseudo-second-order kinetic model, whereas the adsorption isotherms were best fitted by the Sips model. The XLT 50 % presented good reusability properties, maintaining its adsorption capacity for 3 cycles. Finally, the XLT 50 % presented good adsorptive properties toward other pollutants (methyl orange, 4-chloro-phenol, and hexavalent chromium), indicating its versatility for adsorption processes. (AU)

• FAPESP's process: 17/10118-0 - Study and application of electrochemical technology for the analysis and degradation of endocrine interferents: materials, sensors, processes and scientific dissemination
• Grantee: Marcos Roberto de Vasconcelos Lanza
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/10492-1 - Photocatalytic evaluation of heterojunctions semiconductor/ZnO/carbon xerogel in the photodegradation of 4-chlorophenol in both fluidized bed and batch reactors
• Grantee: Liana Alvares Rodrigues
• Support Opportunities: Regular Research Grants
• FAPESP's process: 18/16360-0 - Development of ZnO/Bi2O3/Carbon xerogel ternary composites as photocatalysts for the degradation of persistent organic pollutants
• Grantee: Nicolas Perciani de Moraes
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 22/04058-2 - Photoelectrocatalytic degradation of pollutants (bisphenol-A, sulfamerazine, and 2,4-D) using H2O2 electrogenerated in carbonaceous matrices obtained from sustainable sources
• Grantee: Nicolas Perciani de Moraes
• Support Opportunities: Scholarships in Brazil - Post-Doctoral