Eco-Efficient Green Seaweed Codium decorticatum Biosorbent for Textile Dyes: Characterization, Mechanism, Recyclability, and RSM Optimization

Abstract

Biosorption using natural waste has emerged as a potential and promising strategy for removal of toxic dyes from wastewaters in comparison to conventional ones. Herein, the Codium decorticatum alga (CDA) was biologically identified and used as a biosorbent for anionic and cationic dyes from aqueous solutions. SEM analysis showed a rough surface with an irregular edge and shape while hydroxyl, amine, sulfur and carboxyl functional groups were identified using FTIR analysis. TGA/DTG confirmed the stability of CDA and the adsorption process. Batch studies were conducted to investigate the effect of operational factors such as initial pH, biosorbent dosage, temperature, initial concentration, and solid/liquid contact time on the biosorption of crystal violet (CV) and Congo red (CR) dyes. For both CV and CR dyes, the biosorption kinetics was accurately described by the pseudo-second-order model and the Langmuir isotherm was found to be best fitted for equilibrium data. Maximum uptake capacities have attained up to 278.46 mg/g for CV and 191.01 mg/g for CR. The CV and CR dye biosorption mechanism was ultimately manifested through the electrostatic interactions. The regeneration study showed that the CDA presents excellent reuse performance up to four consecutive cycles. The process optimization was performed using the response surface methodology based on Box–Behnken design (RSM-BDD). Accordingly, the optimum predicted removal efficiencies using RSM-BBD for CV and CR were obtained, respectively, at 96.9 and 89.8% using a CDA dose of 1.5 g/L, dye concentration of 20 mg/L, pH of 10 for CV, and pH of 4 for CR. Overall, CDA behaves as an efficient, recyclable, cheap, and eco-friendly adsorbent for cleaning-up of dyed effluents.

Synthesis of a green magnetic biopolymer derived from oak fruit hull tannin for the efficient and simultaneous adsorption of a mixture of Malachite Green and Sunset Yellow dyes from aqueous solutions

“…Therefore, various mechanisms such as electrostatic repulsion or attraction, and hydrogen bonding can play a role in the absorption of both dyes. 19,49 In this study, pH 6.5 was considered the optimal pH, which is almost equal to that of the natural aqueous dye solutions. 50 Also, the results presented in Fig.…”

“…6c, as the reaction time increases, the dye removal efficiency increases because over time, with the accumulation of dye molecules in empty sites, the dye concentration decreases, and the dye removal rate increases. 49 3.3. Adsorption investigations: kinetic and isotherm models, determination of thermodynamic parameters 3.3.1.…”

Phosphorylated cellulose paper as highly efficient adsorbent for cadmium heavy metal ion removal in aqueous solutions

“…7,8 Adsorption, which has gained a great deal of interest, is preferred because of its easy operation, high efficiency, fast pollutant removal rate, eco-friendly nature, low cost, and reversibility. [9][10][11][12][13][14] The commonly reported adsorbents materials are activated carbon, 15,16 zeolite, 17,18 clay, 19 apatite. 20 Despite materials' extensive use and good adsorption performance, the quest for cheap, environmentally benign, and excellent adsorbents is still ongoing.…”

Comparison of green bio-based cerium/alginate vs. copper/alginate beads: a study of vibrational and thermal properties using experimental and theoretical methods

“…Additionally, these interactions are often found in the biosorption process; the use of biosorption in discharge processes to remove toxic metal ions, pigment, and other toxic chemicals components from water, has showed a very high e ciency [30][31][32][33][34][35]. Among the most cost-effectiveness routes to improve the alginate biosorption practice are, the degradation of chemical and biological silts, and rebirth of biosorbents, including the metal recovery prospect [36][37][38][39].…”