Synthesis of Fe3O4 Nanoparticles with Different Shapes Through a Co-Precipitation Method and Their Application

Magnetic Fe3O4 nanoparticles (NPs) were successfully synthesized via co-precipitation method using ferric chloride and ferrous sulphate as the starting materials. The shape and the size of Fe3O4 NPs were controlled by using different types of additive including ammonium hydroxide and sodium hydroxide. The results revealed that by adding ammonium hydroxide, the particles attained a spherical shape with a uniform size. On the other hand, the shape of the particles turned from spherical to cubic using sodium hydroxide. The magnetic results showed that both samples attained hysteresis loop, which indicated that both samples have ferromagnetic behavior. In addition, Fe3O4 NPs with cubic shape showed higher adsorptive behaviour towards Congo red compared to spherical Fe3O4 NPs, which is attributed to the enhancement of their magnetic properties. The adsorption of Congo red onto cubic Fe3O4 NPs was best described by Langmuir isotherm model, while spherical Fe3O4 NPs followed Freundlich isotherm model.Other Information Published in: JOM License: https://creativecommons.org/licenses/by/4.0See article on publisher's website: http://dx.doi.org/10.1007/s11837-022-05380-3</p

Characterization and Separation Performance of a Novel Polyethersulfone Membrane Blended with Acacia Gum

Novel polyethersulfone (PES) membranes blended with 0.1–3.0 wt. % of Acacia gum (AG) as a pore-former and antifouling agent were fabricated using phase inversion technique. The effect of AG on the pore-size, porosity, surface morphology, surface charge, hydrophilicity, and mechanical properties of PES/AG membranes was studied by scanning electron microscopy (SEM), Raman spectroscopy, contact angle and zeta potential measurements. The antifouling -properties of PES/AG membranes were evaluated using Escherichia coli bacteria and bovine serum albumine (BSA). The use of AG as an additive to PES membranes was found to increase the surface charge, hydrophilicity (by 20%), porosity (by 77%) and permeate flux (by about 130%). Moreover, PES/AG membranes demonstrated higher antifouling and tensile stress (by 31%) when compared to pure PES membranes. It was shown that the prepared PES/AG membranes efficiently removed lead ions from aqueous solutions. Both the sieving mechanism of the membrane and chelation of lead with AG macromolecules incorporated in the membrane matrix contributed to lead removal. The obtained results indicated that AG can be used as a novel pore-former, hydrophilizing and antifouling agent, as well as an enhancer to the mechanical and rejection properties of the PES membranes.Other Information Published in: Scientific Reports License: http://creativecommons.org/licenses/by/4.0See article on publisher's website: http://dx.doi.org/10.1038/s41598-017-14735-9</p

Optimizing and control of effective synthesize parameters for Fe3O4 nanoparticles using response surface methodology

To control Fe3O4 nanoparticles (Fe3O4 NPs) size, different molar ratio of Fe2+ and Fe3+ as well as ammonium hydroxide (pH) was used to synthesize Fe3O4 NPs through co-precipitation method. The Box–Behnken design was selected to explore the interaction between process parameters (factors) such as Fe2+ molar ion, Fe3+ molar ion and pH on the final size. The interactive effect between the process variables was evaluated by analysis of variance (ANOVA). The quadratic model predicted by the Box–Behnken design was significant with a P value of Other Information Published in: Chemical Papers License: https://creativecommons.org/licenses/by/4.0See article on publisher's website: http://dx.doi.org/10.1007/s11696-022-02320-y</p

Insight into Biomass as a Renewable Carbon Source for the Production of Succinic Acid and the Factors Affecting the Metabolic Flux toward Higher Succinate Yield

The current world demand for succinic acid is around 30 000 tonnes per annum, which is forecast to expand 6-fold by 2015, owing to the introduction of biosuccinic acid. An insight into the practical usage of different biomass derivatives as substrates in the commercial bioproduction of succinic acid is discussed. Lignocellulosic crop stalk waste (corn straw, rice straw, and cotton straw) appears, in this case, to be the most promising form of biomass for commercial succinic acid fermentation. Another example of a low cost carbon source with high availability, crude glycerol, on the other hand, shows comparable potentials as a sustainable commercial carbon source for biosuccinic acid. In terms of the metabolic pathway of succinate-producing microbes, a greater availability of substrate CO₂ and a lower oxidation/reduction potential (ORP) of the fermentation broth will trigger the microbial metabolic flux toward the generation of highly reduced metabolites (succinate) in order to regain an intracellular redox balance

Adsorption of 4-Nitrophenol onto Iron Oxide Bentonite Nanocomposite: Process Optimization, Kinetics, Isotherms and Mechanism

Despite its importance in chemical industry, 4-Nitrophenol (4-NP) is a persistent organic pollutant that has serious effects on the ecosystem. In the present study, Box–Behnken design in response surface methodology was used to optimize the adsorption process parameters for the maximum 4-NP removal at 30 ℃ using Fe3O4/Bt NC. The regression model results suggested that the optimum adsorbent dosage, initial concentration, pH and contact time were 0.3182 g, 85 mg/L, 11 and 137.2 min, respectively. The regression model showed an optimum removal of 100%, while 99.5% removal was obtained from batch experiments at the optimum conditions suggested by the regression model, which confirm the model validity. The adsorption data best fitted to Freundlich isotherm model and Pseudo second-order kinetic model suggesting the existence of physical and chemical interaction between the fabricated composite and 4-NP. FTIR analysis suggested that the adsorption mechanism included an electrostatic attraction and the formation of new chemical bonds. Obtained results suggest that Fe3O4/Bt NC can be an effective adsorbent for complete 4-NP removal at the indicated optimum conditions. Graphical AbstractOther Information Published in: International Journal of Environmental Research License: https://creativecommons.org/licenses/by/4.0See article on publisher's website: http://dx.doi.org/10.1007/s41742-022-00402-z</p