Zn-doped CoFe2O4Nanoparticles Synthesized Using Ginkgo Biloba Extract: Cation Distribution, Mossbauer Studies and Application for Water Treatment

The cobalt-zinc ferrites Zn1-xCoxFe2O4 (where x=0; 0.2; 0.4; 0.6; 0.8; 1.0) were obtained by green synthesis using Ginkgo Biloba extract as reductant and fuel. The cation distribution of the spinel ferrites has been investigated by means of X-ray diffraction and Mossbauer spectroscopy. The surface morphology and elemental composition were analyzed by SEM and EDS. The crystallite size decrease with increasing Co2+ content calculated from Scherrer equation and Williamson-Hall method. Adsorption properties of the spinel system were investigated using Congo Red (CR) dye as model pollutant. It is concluded that the adsorption of Congo red dye molecules can occur due to electrostatic and donor-acceptor interactions with the adsorbent surface containing various amount of active centers.

UTILIZATION OF WATER HYACINTH FOR DYE EFFLUENT PURIFICATION

Water hyacinth (Eichhornia crassipes) (WH) is an invasive plant floating freely on the water, which is widely spread in tropical and subtropical regions. The plant is characterized by high porosity and a high number of functional groups, such as hydroxyl (-OH), carboxyl (–COOH), and amino groups (–NH2). Activated carbon, which is widely accepted on an industrial level for the adsorption of dyes from wastewaters, is a highly expensive material. Thus, in this research, a bioadsorbent material was prepared based on WH biomass and investigated as an alternative tool for water quality remediation, in the case of dye pollutants (RR HE3B). The WH plants were collected from the nearby Lake Tana and used as an adsorbent material without chemical treatment. The batch adsorption test was performed by varying the pH of the solution, adsorbent dosage and initial dye concentration. The powdered WH and RR HE3B dye loaded WH were characterized using FTIR, revealing the emergence of new stretching vibration peaks in the range from 2800 to 3000 cm-1 on the spectrum of Reactive Red HE3B (RR HE3B) dye loaded WH, confirming that -CH and -CH2 were responsible for the adsorption. The analysis of the adsorption isotherm and of the suitability of different models for describing it has led to the following order: Freundlich > Langmuir > Temkin > Dubinin-Radushkevich, based on their correlation coefficient value. This implies that the WH adsorbent surface is heterogeneous and the adsorption of the dye onto it depends not only on the specific reaction sites, as the n-value of the Freundlich constant confirms that the physical adsorption process might be favored. Therefore, WH could be a potential alternative adsorbent to remove the RR HE3B dye from dye polluted wastewaters.

Natural Batch Adsorption Operation to Remove Dissolved Copper (II) by Carbon Charcoal Rambutan

Carbon charcoal was made from rambutan rods and used as an adsorbent. A gram 70/100 mesh size of adsorbent was then used to adsorb 100 ml of copper ion solution with a 70 ppm concentration. In this investigation, the batch procedure was used without shaking (naturally). The charcoal carbon rambutan ability to remove the copper ion was measured by AAS. The percentage result was 48,135% or about 33,694 ppm. SEM and EDX instrument analysis have applied to confirm the presence of copper ions on the adsorbent surface. The copper ion was found at a concentration of 0.09 percent of the total weight. The carbon charcoal adsorbent in rambutan rods has the ability to purify the water contaminated by metal ions.

3,5-Dinitrosalicylic Acid Adsorption Using Granulated and Powdered Activated Carbons

Some nitroaromatic compounds are found in wastewater from industries such as the weapons industry or the wine industry. One of these compounds is 3,5-dinitrosalicylic acid (DNS), widely used in various tests and frequently found as an emerging pollutant in wastewater and to which the required attention has not been given, even though it may cause serious diseases due to its high toxicity. This study investigated the adsorption of DNS using granulated activated carbon (GAC) and powdered activated carbon (PAC) at different temperatures. The results show that in equilibrium, the adsorption takes place in more than one layer and is favorable for the removal of DNS in both GAC and PAC; The maximum adsorption capacity was obtained at 45 °C, with values of 6.97 mg/g and 11.57 mg/g, respectively. The process is spontaneous and exothermic. In addition, there was a greater disorder in the solid-liquid interface during the desorption process. The predominant kinetics using GAC (7.14 mg/g) as an adsorbent is Elovich, indicating that there are heterogeneous active sites, and when PAC (10.72 mg/g) is used, Pseudo-second order kinetics predominate, requiring two active sites for DNS removal. External mass transfer limitations are only significant in GAC, and ATR-FTIR studies in PAC demonstrated the participation of functional groups present on the adsorbent surface for DNS adsorption.

Potassium Permanganate Dye Removal from Synthetic Wastewater Using A Novel, Low-Cost Adsorbent, Modified from The Powder of Foeniculum Vulgare Seeds

Seeds powder of Foeniculum vulgare (FVES) was used to prepare a novel adsorbent, the new adsorbent was characterized and its ability to eliminate potassium permanganate (KMnO 4 ) was examined. The impact of KMnO 4 concentration, adsorbent dose, contact temperature, contact time, and solution pH on the adsorption performance was also investigated. The experimental data of this adsorption was analyzed by different kinetic and isotherm models. As Constants of thermodynamic ΔG°, ΔH°, and ΔS° have been also evaluated. Surface area, pore volume, and pore size of the FVESP adsorbent were determined as 0.6806 m 2 .g -1 , 0.00215 cm 3 .g -1 , and 522.063 Å, as pH ZPC of Ox- FVESP was stated to be 7.2. The R 2 values obtained from applying different isotherm and kinetic models (0.999 and 0.996) showed that the adsorption performance of KMnO 4 follows the Langmuir and Pseudo 2 nd order models. Furthermore, high adsorption capacities of 1111.11, 1250.00, and 1428.57 (mg/g) were achieved at three temperatures that were used in this study. Constants of thermodynamic ΔG°, ΔH°, and ΔS° values indicate chemical and spontaneous adsorption at the adsorbent surface.

CO2 Adsorption Performance and Kinetics of Ionic Liquid-Modified Calcined Magnesite

CO2 is a major contributor to global warming, and considerable efforts have been undertaken to capture and utilise it. Herein, a nanomaterial based on ionic liquid (IL)–modified calcined magnesites was investigated for CO2 capture. The synthesised nanomaterial (magnesite modified using [APMIM]Br) exhibited the best adsorption performance of 1.34 mmol/g at 30% IL loading amount, 50 °C, 0.4 MPa and 150 mL/min. In particular, the obtained nanomaterial could be regenerated at a low temperature of 90 °C for 3 h, and its CO2 adsorption capacity of 0.81 mmol/g was retained after eight cycles. FT-IR results showed that the imidazole ring and C–N group are directly related to CO2 adsorption capacity. Moreover, improving the conjugative effect of the imidazole ring enhanced the adsorption performance. Further, CO2 was adsorbed on the adsorbent surface and incomplete desorption decreased the BET surface area and CO2 adsorption capacity. Additionally, four models were selected to fit the adsorption kinetics. The results show that the adsorption mechanism fits the pseudo-first-order model well.

The usage of lignin in two significant applications: As adsorbent surface of water pollutants and antioxidant of plastic polymers: short review

Since pollution is very serious problem threating the environmental eco-system around the world, but people do not usually treat this issue properly. Water is contaminated with different type of pollutants such as organic, inorganic, heavy metals, pesticides, dyes, phenols, and many other pollutants. Using adsorption phenomenon is very practical, easy and common method to remove pollutants from water. Owing to the significant properties of lignin such as high surface area, porosity, availability in huge amount, it was chosen to be used as an adsorbent surface of various pollutants. Herein it is going to review some of important literatures regarding that. Another serious problem that is threatening the marine eco-system, human health, and influence the global warming is the huge consumption of plastic polymers every year. Thus, reducing the consumption of plastic polymers is significantly matter. Lignin chemical structures are highly oxygenated and have several aromatic units, so by definition lignin can act as an antioxidant, free radical scavenger and photo-stabilizers. As the chemical structure of monomer moieties to form lignin are highly aromatic so it is suitable to work as UV- blocker to stop the photo-degradation of plastic.

Effective Adsorptive Removal of Methylene Blue from Water Using Wood- Plastic Composite Containing High Density Polyethylene and Wood Particles

In this study, the ability to remove methylene blue cation pigment using wood-plastic composite containing high density polyethylene and wood powder as a recycled material was studied. The effect of some important parameters such as pH, adsorbent amount and contact time were investigated. Adsorption efficiencies for methylene blue was maximized at alkaline pH. Adsorption capacity increased with increasing adsorbent amount and contact time. The value of R2 in Langmuir model was equal to 1 and the separation factor for 0.5 and 1 g of adsorbent were 0.09 and 0.1, respectively. Given that the methylene blue adsorption data were more consistent with the Langmuir isotherm model, it can be stated that the wood-plastic composite probably has uniform adsorption surfaces and the adsorption process occurred in homogeneous system on the adsorbent surface. Based on the results of this study, it was observed that this composite is a suitable adsorbent for removing methylene blue from aqueous solutions and used as a purifying agent in the decolorization of effluents containing pigments. This adsorbent is recyclable and is cost-effective to remove dye from textile industry wastewater.

Montmorillonite-anchored magnetite nanocomposite for recovery of ammonium from stormwater and its reuse in adsorption of Sc3+

The treatment of stormwater to remove and recover nutrients has received increasing interest. The objective of this study was to develop a novel adsorbent that is easy to handle, has good adsorption capacity, and is economical to use. A novel nanocomposite of montmorillonite (MT)-anchored magnetite (Fe3O4) was synthesised by co-precipitation as an adsorbent for ammonium. The MT/Fe3O4 nanocomposite had pore sizes (3–13 nm) in the range of narrow mesopores. The dispersion of the anchored Fe3O4 was confirmed by transmission electron microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy (XPS). The nanocomposite exhibited higher affinity towards ammonium than the original MT. The Langmuir isotherm model was found to be the most suitable model to explain the ammonium adsorption behaviour of the nanocomposite. The maximum adsorption capacity for ammonium was 10.48 mg/g. The adsorption mechanism was a combination of ion exchange and electrostatic interaction. In an authentic stormwater sample, the synthesised adsorbent removed 64.2% of ammonium and reduced the amount of heavy metal contaminants including Mn, Ni, Cu and Zn. Furthermore, the ammonium loading on MT/Fe3O4 during adsorption functionalised the adsorbent surface. Additionally, the spent nanocomposite showed potential for rare earth elements (REEs) adsorption as a secondary application, especially for the selective adsorption of Sc3+. The versatile application of montmorillonite-anchored magnetite nanocomposite makes it a promising adsorbent for water treatment. Graphic abstract

Carboxyl Methyl Cellulose@Guar Gum@ CuO Nanoparticle as Effective Adsorbent for the Removal of Dye From Aqueous Solution

In the present study, the study and fabrication of inorganic organic nanocomposites with Guar gam and Carboxy methyl cellulose biopolymer substrates. The synthesis nanocomposite of CMC/GG/CuO-3 is biodegradable and biocompatible, and also has a significant efficiency in removing malachite green (MG) dye from aqueous solution. Properties were evaluated by XRD, FTIR, SEM, EDX and BET analysis. Important and influential parameters on the adsorption process such as adsorbent amount, initial dye concentration, pH and contact time on the removal efficiency of contaminants from aqueous solutions were investigated. Maximum removal efficiency and adsorption capacity were 92.4% and 18.6 mg/g, respectively. In order to analyze the mechanism of experimental data, two First-order and Second-order kinetic models were used, which followed the second-order kinetics with R2=1. Also, the study of Freundlich and Langmuir isotherms showed that the isotherm model of Freundlich follows the R2=0.94, which indicates the non-uniformity of adsorption on the adsorbent surface.