Modification of sugarcane bagasse with iron(III) oxide-hydroxide to improve its adsorption property for removing lead(II) ions

Cationic oxides and dioxides of modified sugarcane bagasse beads with applications as low-cost sorbents for direct red 28 dye

The direct red 28 (DR28) dye contamination in wastewater blocks the transmission of light into the water body resulting in the inability to photosynthesize by aquatic life. In addition, it is difficult to break down and persist in the environment, and it is also harmful to aquatic life and water quality because of its aromatic structure. Thus, wastewater contaminated with dyes is required to treat before releasing into the water body. Sugarcane bagasse beads (SBB), sugarcane bagasse modified with titanium dioxide beads (SBBT), sugarcane bagasse modified with magnesium oxide beads (SBBM), sugarcane bagasse modified with aluminum oxide beads (SBBA), and sugarcane bagasse modified with zinc oxide beads (SBBZ) for DR28 dye removal in aqueous solution, and they were characterized with several techniques of BET, FESEM-FIB, EDX, FT-IR, and the point of zero charges (pHpzc). Their DR28 dye removal efficiencies were examined through batch tests, adsorption isotherms, and kinetics. SBBM had the highest specific surface area and pore volume, whereas its pore size was the smallest among other materials. The surfaces of SBB, SBBM, SBBT, and SBBA were scaly sheet surfaces with an irregular shape, whereas SBBZ was a coarse surface. Oxygen, carbon, calcium, chloride, sodium, O-H, C-H, C=O, C=C, and C-O-C were found in all materials. The pHpzc of SBB, SBBT, SBBM, SBBA, and SBBZ were 6.57, 7.31, 10.11, 7.25, and 7.77. All materials could adsorb DR28 dye at 50 mg/L by more than 81%, and SBBM had the highest DR28 dye removal efficiency of 94.27%. Langmuir model was an appropriate model for SBB, whereas Freundlich model was a suitable model for other materials. A pseudo-second-order kinetic model well described their adsorption mechanisms. Their adsorptions of the DR28 dye were endothermic and spontaneous. Therefore, they were potential materials for adsorbing DR28 dye, especially SBBM.

Kinetic and equilibrium study of graphene and copper oxides modified nanocomposites for metal ions adsorption from binary metal aqueous solution

Presently, the main cause of pollution of natural water resources is heavy metal ions. The removal of metal ions such as nickel (Ni2+) and cadmium (Cd2+) has been given considerable attention due to their health and environmental risks. In this regard, for wastewater treatment containing heavy metal ions, graphene oxide (GO) nanocomposites with metal oxide nanoparticles (NPs) attained significant importance. In this study, graphene oxide stacked with copper oxide nanocomposites (GO/CuO-NCs) were synthesized and characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and atomic force microscopy (AFM) analytical procedures. The prepared GO/CuO-NCs were applied for the removal of Ni2+ and Cd2+ ions from a binary metal ion system in batch and continuous experiments. The obtained results revealed that GO/CuO-NCs exhibited the highest removal efficiencies of Ni2+ (89.60% ± 2.12%) and Cd2+ (97.10% ± 1.91%) at the optimum values of pH: 8, dose: 0.25 g, contact time: 60 min, and at 50 ppm initial metal ion concentration in a batch study. However, 4 mL/min flow rate, 50 ppm initial concentration, and 2 cm bed height were proved to be the suitable conditions for metal ion adsorption in the column study. The kinetic adsorption data exhibited the best fitting with the pseudo-second-order model. The adsorption isotherm provided the best-fitting data in the Langmuir isotherm model. This study suggested that the GO/CuO nanocomposites have proved to be efficient adsorbents for Ni2+ and Cd2+ ions from a binary metal system.

Influence of duck eggshell powder modifications by the calcination process or addition of iron (III) oxide-hydroxide on lead removal efficiency

Lead-contaminated wastewater causes toxicity to aquatic life and water quality for water consumption, so it is required to treat wastewater to be below the water quality standard before releasing it into the environment. Duck eggshell powder (DP), duck eggshell powder mixed iron (III) oxide-hydroxide (DPF), calcinated duck eggshell powder (CDP), and calcinated duck eggshell powder mixed iron (III) oxide-hydroxide (CDPF) were synthesized, characterized, and investigated lead removal efficiencies by batch experiments, adsorption isotherms, kinetics, and desorption experiments. CDPF demonstrated the highest specific surface area and pore volume with the smallest pore size than other materials, and they were classified as mesoporous materials. DP and DPF demonstrated semi-crystalline structures with specific calcium carbonate peaks, whereas CDP and CDPF illustrated semi-crystalline structures with specific calcium oxide peaks. In addition, the specific iron (III) oxide-hydroxide peaks were detected in only DPF and CDPF. Their surface structures were rough with irregular shapes. All materials found carbon, oxygen, and calcium, whereas iron, sodium, and chloride were only found in DPF and CDPF. All materials were detected O-H, C=O, and C-O, and DPF and CDPF were also found Fe-O from adding iron (III) oxide-hydroxide. The point of zero charges of DP, DPF, CDP, and CDPF were 4.58, 5.31, 5.96, and 6.75. They could adsorb lead by more than 98%, and CDPF illustrated the highest lead removal efficiency. DP and CDP corresponded to the Langmuir model while DPF and CDPF corresponded to the Freundlich model. All materials corresponded to a pseudo-second-order kinetic model. Moreover, they could be reusable for more than 5 cycles for lead adsorption of more than 73%. Therefore, CDPF was a potential material to apply for lead removal in industrial applications.

Synthesis, characterization, and lead removal efficiency of orange peel powder and orange peel powder doped iron (III) oxide-hydroxide

Lead contamination in wastewater causes toxicity to aquatic life, the environment, and water quality, and it causes many human dysfunctions and diseases. Thus, it is necessary to remove lead from wastewater before discharging it into the environment. Orange peel powder (OP) and orange peel powder doped iron (III) oxide-hydroxide (OPF) were synthesized, characterized, and investigated lead removal efficiencies by batch experiments, adsorption isotherms, kinetics, and desorption experiments. The specific surface area of OP and OPF were 0.431 and 0.896 m²/g, and their pore sizes were 4.462 and 2.575 nm, respectively which OPF had a higher surface area than OP, whereas its pore size was smaller than OP. They were semi-crystalline structures that presented the specific cellulose peaks, and OPF also detected the specific iron (III) oxide-hydroxide peaks. The surface morphologies of OP and OPF were irregular and porous surfaces. Carbon (C), oxygen (O), calcium (Ca), O-H, C-H, C=C, C-O, C=O, and -COOH were observed in both materials. The pH_pzc of OP and OPF were 3.74 and 4.46. For batch experiments, OPF demonstrated a higher lead removal efficiency than OP because of spending less on material dosage than OP, and OPF demonstrated high lead removal by more than 95% while OP could remove lead at only 67%. Thus, the addition of iron (III) oxide-hydroxide helped to increase material efficiency for lead adsorption. Both materials corresponded to the Freundlich model relating to physiochemical adsorption, and they also corresponded to a pseudo-second-order kinetic model relating to a chemisorption process. Moreover, both materials could be reusable for more than 5 cycles for lead adsorption of more than 55%. Therefore, OPF was potential material to apply for lead removals in industrial applications.

Co-Carbonized Waste Polythene/Sugarcane Bagasse Nanocomposite for Aqueous Environmental Remediation Applications

The conversion of worthless municipal solid wastes to valuables is a major step towards environmental conservation and sustainability. This work successfully proposed a technique to utilize the two most commonly available municipal solid wastes viz polythene (PE) and sugarcane bagasse (SB) for water decolorization application. An SBPE composite material was developed and co-pyrolyzed under an inert atmosphere to develop the activated SBPEAC composite. Both SBPE and SBPEAC composites were characterized to analyze their morphological characteristics, specific surface area, chemical functional groups, and elemental composition. The adsorption efficacies of the composites were comparatively tested in the removal of malachite green (MG) from water. The SBPEAC composite had a specific surface area of 284.5 m²/g and a pore size of ~1.33 nm. Batch-scale experiments revealed that the SBPEAC composite performed better toward MG adsorption compared to the SBPE composite. The maximum MG uptakes at 318 K on SBPEAC and SBPE were 926.6 and 375.6 mg/g, respectively. The adsorption of MG on both composites was endothermic. The isotherm and kinetic modeling data for MG adsorption on SBPEAC was fitted to pseudo-second-order kinetic and Langmuir isotherm models, while Elovich kinetic and D-R isotherm models were better fitted for MG adsorption on SBPE. Mechanistically, the MG adsorption on both SBPE and SBPEAC composites involved electrostatic interaction, H-bonding, and π-π/n-π interactions.

Zeolite A powder and beads from sugarcane bagasse fly ash modified with iron(III) oxide-hydroxide for lead adsorption

The discharging of lead-contaminated wastewater is a concern because of its toxicity to living organisms and water quality resulting in dangerous water consumption, so it is highly recommended to remove lead from wastewater to be below water quality standards for a safe environment. Zeolite A sugarcane bagasse fly ash powder (ZB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide (ZBF), zeolite A sugarcane bagasse fly ash beads (ZBB), zeolite A sugarcane bagasse fly ash powder mixed iron(III) oxide-hydroxide beads (ZBFB), and zeolite A sugarcane bagasse fly ash beads coated iron(III) oxide-hydroxide (ZBBF) were synthesized and characterized in various techniques. Their lead removal efficiencies were investigated by batch experiments, adsorption isotherms, and kinetics. The specific surface area, pore volume, and pore size of ZB were close values to zeolite A standard (STD), and ZBF had the highest specific surface area and the smallest pore size than others. ZB and ZBF demonstrated crystalline phases whereas ZBB, ZBFB, and ZBBF were amorphous phases. The surface morphology of ZB was a cubic shape similar to STD. ZBF demonstrated an agglomerated formation of ZB and iron(III) oxide-hydroxide whereas ZBFB and ZBBF had sphere shapes with coarse surfaces. Si, Al, O, Fe, Na, Ca, O-H, (Si, Al)-O, H₂O, and D₄R were detected in all materials. The surface charges of all zeolite A materials had negatively charged at all pH values, and their surfaces increased more negatively charged with increasing pH value which pH 5 illustrated as the highest negatively charged in all materials. Their lead removal efficiencies were higher than 82%. Langmuir isotherm and pseudo-second-order kinetic models were well explained for their adsorption patterns and mechanisms. Finally, ZBBF is a good offer for applying in industrial wastewater treatment systems because of its easy operation and saving costs than ZBF.