Evaluation and mathematical modeling of foam-mat drying of Momordica charantia L. leaves.

This study aimed to analyze the influence of operational parameters (foaming agent concentration, agitation time, and drying temperature) on the characteristics of the final product and the foam drying process of Momordica charantia L. leaves, in addition to performing mathematical modeling of the experimental data. The foam characteristic was most influenced by the foaming agent concentration, where the increase in this variable increased its stability, reaching the highest index of 0.

Synthesis of superparamagnetic FeO-graphene oxide-based material for the photodegradation of clonazepam.

The global concern over water pollution caused by contaminants of emerging concern has been the subject of several studies due to the complexity of treatment. Here, the synthesis of a graphene oxide-based magnetic material (GO@FeO) produced according to a modified Hummers' method followed by a hydrothermal reaction was proposed; then, its application as a photocatalyst in clonazepam photo-Fenton degradation was investigated. Several characterization analyses were performed to analyze the structure, functionalization and magnetic properties of the composite.

Separation of the heme protein cytochrome using a 3D structured graphene oxide bionanocomposite as an adsorbent.

Proteins are of great importance for medicine and the pharmaceutical and food industries. However, proteins need to be purified prior to their application. This work investigated the application of a hydrogel bionanocomposite based on agar and graphene oxide (GO) for capturing cytochrome (Cyto ) heme protein by adsorption from aqueous solutions with other proteins.

Isotherms, kinetics and thermodynamics of industrial dye acid red 27 adsorption on Sugarcane Bagasse Ash.

In this study, sugarcane bagasse ash (SCBA), obtained as residue from the sugar mill, was used as an adsorbent for Acid Red 27 (AR27) removal from aqueous solutions. The ash characterization data showed 23.63% of organic compounds and silica (α-SiO) as the most expressive inorganic compound (confirmed by X-ray diffractogram), the BET surface area had a value of 62.

Agar/graphene oxide hydrogels as nano-bioadsorbents: a comparative analysis for dye removal.

Nano-biocomposite hydrogel samples were produced using graphene oxide (GO) and agar and applied as adsorbents of organic components in water. The hydrogels were prepared by varying the wt% of Agar and GO. The samples were characterized, and batch adsorption experiments evaluated the effect of initial pH, equilibrium isotherms, and kinetics for the adsorption of the anionic dye Acid Orange 7 (AO) and the cationic dyes Nile Blue A (NB) and methylene blue (MB) in an aqueous medium.

Multi-pollutant biosorption of organic and inorganic pollutants by brown algae waste from alginate production: batch and fixed-bed investigation.

The reuse of biomass waste has been gaining attention in adsorption processes to remove pollutants of emerging concern from water and wastewater. In this work, the potential of alginate-extracted macro-algae waste to uptake synthetic dyes and metal cations was evaluated in comparison with raw algae. In affinity assays, both materials were able to remove metal cations and cationic dyes up to maximum rates, and no significant removal was observed for an anionic dye in an acidic medium.

Adsorption of chloroquine, propranolol, and metformin in aqueous solutions using magnetic graphene oxide nanocomposite.

The work proposes the application of a nanocomposite formed by graphene oxide and magnetite to remove chloroquine, propranolol, and metformin from water. Tests related to adsorption kinetics, equilibrium isotherms and adsorbent reuse were studied, and optimization parameters related to the initial pH of the solution and the adsorbent dosage were defined. For all pharmaceuticals, adsorption tests indicated that removal efficiency was independent of initial pH at adsorbent dosages of 0.

Adsorption of Cd (II) ions and methyl violet dye by using an agar-graphene oxide nano-biocomposite.

In this work, an agar-graphene oxide hydrogel was prepared to adsorb Cd (II) and Methyl Violet (MV) from water. The hydrogel was synthesised and characterised through SEM and EDS. Kinetic, equilibrium and regeneration studies were carried out, in which Langmuir, Freundlich and Sips isotherm models were fitted to the equilibrium experimental data; and regarding the kinetics, studies were conducted by modelling experimental data considering both empirical and phenomenological models.

Continuous removal of pharmaceutical drug chloroquine and Safranin-O dye from water using agar-graphene oxide hydrogel: Selective adsorption in batch and fixed-bed experiments.

In this work, Chloroquine diphosphate, and the cationic dye Safranin-O were selectively removed from water using the agar-graphene oxide (A-GO) hydrogel, produced via simple one-step jellification process. The morphology of the A-GO biocomposite was characterized and batch experiments were performed, with adsorption isotherms satisfactorily fitting (R > 0.98) Sips (Safranin-O) and Freundlich (Chloroquine) isotherms.

Synthesis and application of graphene oxide as a nanoadsorbent to remove Cd (II) and Pb (II) from water: adsorption equilibrium, kinetics, and regeneration.

In this work, graphene oxide (GO) was synthesized by the modified Hummers method. The nanomaterial was characterized by FTIR and Raman spectroscopy, SEM, and pH at the point of zero charge. GO exhibited typical characteristics of graphene-based materials, indicating that graphite oxidation and exfoliation occurred successfully.

Removal of textile dyes by benefited marine shells wastes: From circular economy to multi-phenomenological modeling.

Marine shell wastes were thermally activated and characterized as aragonite and calcite phases and were used in the removal of synthetic anionic dyes, Bright Blue Acid (NB180) and Reactive Red 133 (RR133). Benefited marine shells were classified as low-cost (USD 0.33/g of adsorbent) in comparison with other reported materials.

Detoxification of sisal bagasse hydrolysate using activated carbon produced from the gasification of açaí waste.

Due to its recalcitrance and difficult disruption, biomass requires severe treatment conditions to produce bioproducts. These processes also generate substances that inhibit microbial metabolism, resulting in low conversion of sugars into bioproducts. To minimize this, in this work the sisal bagasse acid hydrolysate was detoxified using the activated carbon obtained from residues of the gasification of açaí endocarp.

In-depth investigation of Sodium percarbonate as oxidant of PAHs from soil contaminated with diesel oil.

Sodium percarbonate (SPC, 2NaCO∙3HO), is a compound that can be used under multiple environmental applications. In this work, SPC was employed as oxidant in the treatment of soil contaminated with diesel oil. The soil samples were collected during the earthmoving stage of RNEST Oil Refinery (Petrobras), Brazil.

Adsorptive and photocatalytic activity of FeO-functionalized multilayer graphene oxide in the treatment of industrial textile wastewater.

Multilayer graphene oxide (mGO) was synthesized and functionalized via co-precipitation method to produce magnetic FeO-functionalized multilayer graphene oxide nanocomposite (MmGO). Photocatalytic properties of MmGO were investigated in the photodegradation of raw textile wastewater samples. Fourier-transformed infrared spectroscopy revealed Fe-O vibrations, characterized by the band shift from 636.

Investigation of paracetamol degradation using LED and UV-C photo-reactors.

This work investigates the efficiency of LED and UV-C photo-reactors for paracetamol degradation using advanced oxidative processes. Among the evaluated processes, photo-Fenton was the most efficient for both radiations. Degradations greater than 81% (λ 197 nm) and 91% (λ 243 nm) were obtained in the kinetic study.

One step forward: How can functionalization enhance the adsorptive properties of graphene towards metallic ions and dyes?

Functionalized graphene and its derivatives have been subject of many recent studies investigating their use as scavenger of various industrial pollutants. Adsorption is a feasible treatment, which can employ a wide variety of materials as adsorbents. Additionally, graphene has been distinguished for its remarkable properties, such as mechanical resistance, flexibility and electric conductivity.

Amino-FeO-functionalized multi-layered graphene oxide as an ecofriendly and highly effective nanoscavenger of the reactive drimaren red.

Amino-functionalized multilayer graphene oxide (Am-nGO) has been synthesized and applied to remove the reactive drimaren red (DR) from aqueous solutions. Infrared spectroscopy evidenced amine and amide presence by peaks at 1579 cm and a band between 3300 and 3500 cm. Raman spectroscopy showed an increment in I/I ratio after amino-FeO-functionalization of nGO from 1.

Graphene-based materials production and application in textile wastewater treatment: color removal and phytotoxicity using as bioindicator.

The dyes used in textile industries are usually difficult to degrade in aquatic environments, being highly toxic to micro fauna and flora. Thus, textile wastewater treatments have been developed, among them, one that stands out is adsorption process. With the rise of nanomaterials applied to adsorption, graphene oxide (GO) shows promise in the removal of dyes.

Environmentally friendly route for graphene oxide production via electrochemical synthesis focused on the adsorptive removal of dyes from water.

This work shows a promising, environmentally friendly and greener alternative for the production and application of electrochemically produced Graphene Oxide (GO) for the adsorptive removal of Methylene Blue (MB) dye in an aqueous medium. During the adsorption tests, GO produced via electrochemical route reached the equilibrium in only 10 min of contact, exhibiting a percentage removal of MB over 97%. It could also be observed that the experimental data better fitted to the pseudo-second order kinetic model.

Removal of azo dye from water via adsorption on biochar produced by the gasification of wood wastes.

It was the aim of this work to evaluate the adsorptive performance of the biochar obtained from the gasification of wood residues onto a solution of Indosol Black NF1200 dye. The study was performed by means of factorial design 2, having as control variables: pH and adsorbent's granulometry. Batch tests were carried out at 200 rpm for 3 h (T = 28 °C).

Anomalocardia brasiliana shellfish shells as a novel and ecofriendly adsorbent of Nylosan Brilliant Blue acid dye.

Malacoculture waste (Anomalocardia brasiliana) shellfish shells (ABSS) were evaluated as adsorbents of Nylosan Brilliant Blue (NBB) acid dye. The ABSS were thermally activated at 1,000 °C for 10 h and then characterized by Fourier-transform infrared spectroscopy, analysis of specific surface area (BET), X-ray diffraction (XRD), and scanning electron microscopy. Point of zero charge (PZC) analysis of ABSS verified pH 13.

Treated residue from aluminium lamination as adsorbent of toxic reactive dyes - a kinetic, equilibrium and thermodynamic study.

The residue generated in the aluminium cold lamination (TTR) was submitted to a direct burning and then it was calcined at 500°C. BET, FTIR, SEM with EDX and TGA techniques were performed to characterize the adsorbent before and after the adsorption. BET analysis showed that TTR specific surface area was 55.