Effective removal of basic dye onto sustainable chitosan beads: Batch and fixed-bed column adsorption, beads stability and mechanism

Author(s)

Morais da Silva, Paula Mayara ^[1] ; Camparotto, Natalia Gabriele ^[1] ; Neves, Tauany de Figueiredo ^[1] ; Grego Lira, Katherly Taina ^[1] ; Mastelaro, Valmor Roberto ^[2] ; Franco Picone, Carolina Siqueira ^[3] ; Prediger, Patricia ^[1]

Affiliation

^[1] Univ Estadual Campinas, Sch Technol, UNICAMP, BR-13484332 Limeira, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Inst Phys, BR-13566590 Sao Carlos, SP - Brazil

^[3] Univ Estadual Campinas, Sch Food Engn, UNICAMP, BR-13083862 Campinas, SP - Brazil

• Document type: Journal article
• Source: SUSTAINABLE CHEMISTRY AND PHARMACY; v. 18, DEC 2020.
• Web of Science Citations: 0

Abstract

This study aims to develop sustainable low-cost chitosan-based beads by a simple dropping method, with instantaneous formation by reticulation with tripolyphosphate anion. The beads were characterized and applied to basic blue 7 (BB7) uptake. The adsorption process was optimized through variation of several parameters in batch experiments such as bead loading, pH, dye concentration and temperature. At a BB7 concentration of 400 mg/L and 60 min, the best BB7 adsorption capacity (1410 mg/g) and partition coefficient (8.22 mg/g/mu M) were achieved by chitosan beads, which were quite superior to others described in the literature. The obtained data best fitted to mixedand pseudo-first order kinetic models and to Redlich-Peterson isothermal model. A fixed-bed column experiment was conducted and the adsorption capacity and partition coefficient at 100% breakthrough were 12.06 mg/g and 0.06 mg/g/mu M. The bead storage study indicated that its adsorption capacity was not affected for a two-week period and reached 325 mg/g. Also, the presence of basic brown 4 (BB4) dye did not harm basic blue 7 in the simultaneous adsorption process and a removal capacity of 232 and 259 mg/g was reached for BB4 and BB7 dye, respectively. The presence of NaCl reduced the percentage of BB7 removal from 91% to 73%. The removal mechanism based on XPS, FTIR and BET analyses suggests that hydrogen bonds are the main adsorption mechanism followed by cation-exchange. This study gave rise to encouraging results and chitosan/tripolyphosphate beads proved to be potential adsorbents for industrial effluent treatments. (AU)

• FAPESP's process: 13/07296-2 - CDMF - Center for the Development of Functional Materials
• Grantee: Elson Longo da Silva
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 19/07822-2 - Synthesis of new nanoadsorbents, their characterizations and applications in pollutant adsorption in water
• Grantee: PATRICIA PREDIGER
• Support Opportunities: Regular Research Grants
• FAPESP's process: 19/25228-0 - Development of new membranes based on graphene oxide for the removal of contaminants in water
• Grantee: Tauany de Figueiredo Neves
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)