The potential of glycine max pod (GMP) in removal of Cd 2+ , Ni 2+ and Cr 6+ ions from aqueous solutions was examined in a batch adsorption process with respect to several experimental conditions including pH of solution, contact time, GMP dosage, initial metal ions concentration, and temperature, etc. The characterization of GMP was performed by using FTIR and SEM techniques. The maximum uptake of Cd 2+ (1.445 mg/g), Ni 2+ (1.585 mg/g) and Cr 6+ (1.594 mg/g) was observed when used 2.0g of GMP biomass, 25 mgL -1 of initial Cd 2+ , 50 mg/l of initial Ni 2+ and 50 mg/l of initial Cr +6 concentration at pH 5, 6 and 3 and contact time of 90, 60 and 90 min at room temperature for Cd 2+ , Ni 2+ and Cr 6+ respectively. The experimental data were analyzed by the Langmuir, Freundlich, Temkin and Dubinin-Radushkevich (D-R) isotherm models. The monolayer adsorption capacity Of GMP was found to be 21.56 mg/g, 53.76 mg/g and 18.87 mg/g for Cd 2+ , Ni 2+ and Cr 6+ ions, respectively. The kinetics of the adsorption was tested using pseudofirst-order, pseudo-second-order, Elovich and intra-particle diffusion models. The results showed that the adsorption of Cd 2+ , Ni 2+ and Cr 6+ ions onto GMP proceeds according to the pseudo-second-order model.
Brick is one of largest material used in construction of infrastructure all over the world. A conventional bricks such as clay brick and concrete brick are produced from clay with high temperature kiln firing and from ordinary Portland cement (OPC) concrete respectively. Both of this activities lead to CO2 emission. The burning process requires high temperature at the same time release carbon dioxide and pollute the environment. At present, carbon emissions has become a crucial issues in the society that must be solved. Several studies had demonstrated that brick can be produced from bacteria based on Microbial Induced Calcite Precipitation (MICP). The objective of this study is to develop cement free- brick from vegetables waste with added eggshell as calcium additive to induce biocementation of brick. Brick specimen was cast in the mould size 210 x 90 x 65 mm and casting for 28 days. The study showed that there was an increased in compressive strength up to 0.062 N/mm2 as the curing period increased to 28 days which showed the occurrence of biocementation activities. SEM-EDX analysis confirmed the presence of calcite precipitation. The result indicated that vege-grout can be used as binding agent for biocementation to produce bricks.
In this study modified feldspar composite (MFC) adsorbent based on feldspar and Theobroma cacao podas (TCP) was prepared, characterized and utilized for adsorption of Pb (II) and Cr (VI) in aqueous solution. The results showed that the cation exchange capacity of the modified feldspar composite (30.66 ± 0.21 meq/100 g) was 5 times higher than that of raw feldspar (6.42 ± 0.45 meq/100g). More so, the novel biohybrid material, MFC has a surface area of 53.60 ± 0.3 m2/g and particle size of 105.4 ± 0.18. X-ray diffraction peaks revealed that after the modification process, there is only slight shift in the position of some diffraction peaks of feldspar and the composite material suggestive of the retention of the crystalline properties of the feldspar in the novel composite (MFC). Infrared spectroscopy (FTIR) spectra showed that some functional groups present in the two starting materials were also available on the surface of the composite (MFC) indicating that the intercalation of TCP biomass into feldspar surface was successful. Response surface methodology (RSM) via a five-levels central composite design (CCD) was applied for optimization of metal adsorption onto the adsorbent in 32 experiment runs considering the effect of pH, adsorbent dose, adsorbate concentration and contact time. Optimization results showed that the predicted and experimental values of Pb (14.021, 14.148 mg/g) and Cr (3.428, 3.504 mg/g) were close at the optimum condition of (pH 2, 5, 6; 0.5 g; 100 mg/L; 60-120 min and 3000K). Results of ANOVA analysis revealed the adequacy of the model with the good correlation between R2 values (0.9916-0.9998) and adjusted R2 (0.9919-0.9986) and F value of (≥ 147). Results showed that Pb (II) ions adsorption onto the adsorbents was well fitted to the Langmuir isotherm model while the Cr (VI) ions uptake onto FS and MFC adsorbents followed Freundlich isotherm model. The results of the kinetic studies showed that rate of Pb (II) removal followed pseudo second order model while the rate of adsorption of Cr (VI) onto the FS and MFC adsorbents best fitted pseudo first order model. Owing to its improved cation exchange capacity and eco-friendliness, the modified feldspar composite have a good potential application in wastewater treatment besides other industrial explorations.
In this study modified feldspar composite (MFC) adsorbent based on feldspar and Theobroma cacao pods (TCP) was prepared using calcination method, characterized and tested for the removal As (III) from aqueous solution. The results showed that the cation exchange capacity of the modified feldspar composite (30.66 ± 0.21 meq/100 g) was 5 times higher than that of raw feldspar (6.42 ± 0.45 meq/100g). More so, the novel biohybrid material, MFC has a surface area of 53.60 ± 0.3 m2/g and particle size of 105.4 ± 0.18. Response surface methodology (RSM) via central composite design (CCD) was utilized in the optimization of the efficiency of As (III) ions uptake by the novel composite (MFC) in 20 experiment runs. The optimization results revealed that predicted adsorption percentages of (99.72%) for As (III) ions was close to the experimental results (99.98%) for the metal ions at the optimum conditions of adsorption parameters (pH 5; 0.5 g; 100 mg/L; 120 min and 3280K). The adequacy and validation of the model was justified with the good agreement between R2 values (0.9959) and adjusted R2 (0.9981) and higher F values (≥ 147) from the analysis of variance (ANOVA) results. Furthermore, the results from isotherm studies showed that As (III) ions adsorption onto the adsorbent best fitted the Langmuir isotherm model, hence chemisorption process. The results of the kinetic studies showed that the rate of uptake of As (III) ions onto MFC active sites followed pseudo second order kinetic model. The Intraparticle diffusion though not the only rate - controlling step, played an important role in the metal ions uptake by the adsorbent. The thermodynamic results revealed that As (III) adsorption onto MFC surface was feasible, spontaneous with negative ∆H values, suggestive of exothermic process. The MFC, owing to its abundance and other properties as its improved cation exchange capacity and eco-friendliness has a good potential as a highly efficient alternative adsorbent to commercial activated carbons in water treatment.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.