Bonding Behavior and Mechanism of U(VI) by Chemically Modified Deinococcus radiodurans

The goal of this study is to understand the role of various functional groups on the cell surface when the microorganisms are exposed to uranium (U(VI)). The biomass of Deinococcus radiodurans was subjected to chemical treatments to modify the carboxyl (-C=O), amino (-NH2), phosphate (-PO2−), and hydroxyl (-OH) groups, as well as the lipid fraction. The behavior and process of U(VI) biosorption by Deinococcus radiodurans were ascertained, followed by scanning electron microscopy (SEM) combined with energy disperse spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) analyses. Carboxyl esterification and amino methylation deteriorated the removal efficiency by 8.0% and 15.5%, respectively, while lipid extraction, phosphate esterification, and hydroxyl methylation improved the removal efficiency by 11.7%, 8.7%, and 4.1%, respectively. The kinetic results revealed that uranium biosorption behavior by the raw and chemically modified biomass fitted well with the model of pseudo-second-order kinetic (R2 = 0.9949~0.9998). FTIR and SEM-EDS indicated that uranium initially bound with the raw and chemically modified Deinococcus radiodurans, which was probably controlled by ion exchange at the first stage, followed by complexation with the -C=O and -NH2 groups, which especially prefer to bond with P and O atoms on the -PO2− group.

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Synthesis of Functionalized Magnetite Titanium Dioxide Nanocomposite for Removal of Acid Fuchsine Dye

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207321666181019111211 ◽

2018 ◽

Vol 21 (8) ◽

pp. 583-593 ◽

Cited By ~ 1

Author(s):

Sara Rahnama ◽

Shahab Shariati ◽

Faten Divsar

Keyword(s):

Titanium Dioxide ◽

Removal Efficiency ◽

Magnetic Core ◽

Fractional Factorial ◽

Order Kinetic ◽

Sorption Data ◽

Salt Addition ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Ft Ir

Objective: In this research, a novel magnetite titanium dioxide nanocomposite functionalized by amine groups (Fe3O4@SiO2@TiO2-NH2) was synthesized and its ability for efficient removal of Acid Fuchsine as an anionic dye from aqueous solutions was investigated. Method: The core-shell structure of Fe3O4@SiO2@TiO2 was prepared using Fe3O4 as magnetic core, tetra ethyl orthosilicate as silica and tetra butyl titanate as titanium source for shell. The synthesized nanocomposites (particle size lower than 44 nm) were characterized by FT-IR, XRD, DRS, SEM and TGA instruments. The various experimental parameters affecting dye removal efficiency were investigated and optimized using Taguchi fractional factorial design. Results: The synthesized adsorbent showed the highest removal efficiency of Acid Fuchsine (99 %) at pH= 3.5, without salt addition and during stirring at contact times less than 10 minutes. The study of kinetic models at two concentration levels showed the fast dye sorption on the surface of proposed nanocomposites with pseudo second order kinetic model (R2=1). Also, the fitting of Acid Fuchsine sorption data to Freundlich, Langmuir and Temkin isotherms suggested that Freundlich model gave a better fitting than other models (R2=0.9936, n=2). Conclusion: Good chemical stability, excellent magnetic properties, very fast adsorption kinetics and high removal efficiency make the synthesized nanocomposite as a proper recoverable sorbent for removal of Acid Fuchsine dye from wastewaters.

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Molybdenum Trioxide: Efficient Nanosorbent for Removal of Methylene Blue Dye from Aqueous Solutions

Molecules ◽

10.3390/molecules23092295 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2295 ◽

Cited By ~ 10

Author(s):

Souad Rakass ◽

Hicham Oudghiri Hassani ◽

Mostafa Abboudi ◽

Fethi Kooli ◽

Ahmed Mohmoud ◽

...

Keyword(s):

Methylene Blue ◽

Aqueous Solutions ◽

Removal Efficiency ◽

Molybdenum Trioxide ◽

Second Order ◽

Blue Dye ◽

Order Kinetic ◽

Methylene Blue Dye ◽

Removal Capacity ◽

Pseudo Second Order

Nano Molybdenum trioxide (α-MoO3) was synthesized in an easy and efficient approach. The removal of methylene blue (MB) in aqueous solutions was studied using this material. The effects of various experimental parameters, for example contact time, pH, temperature and initial MB concentration on removal capacity were explored. The removal of MB was significantly affected by pH and temperature and higher values resulted in increase of removal capacity of MB. The removal efficiency of Methylene blue was 100% at pH = 11 for initial dye concentrations lower than 150 ppm, with a maximum removal capacity of 152 mg/g of MB as gathered from Langmuir model. By comparing the kinetic models (pseudo first-order, pseudo second-order and intraparticle diffusion model) at various conditions, it has been found that the pseudo second-order kinetic model correlates with the experimental data well. The thermodynamic study indicated that the removal was endothermic, spontaneous and favorable. The thermal regeneration studies indicated that the removal efficiency (99%) was maintained after four cycles of use. Fourier Transform Infrared (FTIR) and Scanning Electron Microscopy (SEM) confirmed the presence of the MB dye on the α-MoO3 nanoparticles after adsorption and regeneration. The α-MoO3 nanosorbent showed excellent removal efficiency before and after regeneration, suggesting that it can be used as a promising adsorbent for removing Methylene blue dye from wastewater.

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The Role of Adsorption in the Photocatalytic Decomposition of Dyes on APTES-Modified TiO2 Nanomaterials

Catalysts ◽

10.3390/catal11020172 ◽

2021 ◽

Vol 11 (2) ◽

pp. 172

Author(s):

Ewelina Kusiak-Nejman ◽

Agnieszka Sienkiewicz ◽

Agnieszka Wanag ◽

Paulina Rokicka-Konieczna ◽

Antoni W. Morawski

Keyword(s):

Methylene Blue ◽

Kinetic Models ◽

Second Order ◽

Orange Ii ◽

Order Kinetic ◽

Charged Surface ◽

Surface Charges ◽

Tio2 Nanomaterials ◽

Pseudo Second Order

This work investigated for the first time the role of adsorption in the photocatalytic degradation of methylene blue and Orange II dyes in the presence of 3-aminopropyltriethoxysilane (APTES)-modified TiO2 nanomaterials. It has been demonstrated that the decrease in adsorption has a detrimental effect on photocatalytic activity. APTES/TiO2 photocatalysts were successfully prepared by solvothermal modification of TiO2 in a pressure autoclave, followed by heat treatment in an inert gas atmosphere at the temperature range from 300 °C to 900 °C. It was observed that functionalization of TiO2 via APTES effectively suppressed the anatase-to-rutile phase transformation, as well as the growth of crystallites size during calcination, and reduction of specific surface area (APTES modification inhibits sintering of crystallites). The noted alterations in the adsorption properties, observed after the calcination, were generally related to changes in the surface characteristics, mainly surface charges expressed by the zeta potential. Positively charged surface enhances adsorption of anionic dye (Orange II), while negatively charged surface was better for adsorption of cationic dye (methylene blue). The adsorption process substantially affects the efficiency of the photocatalytic oxidation of both dyes. The methylene blue decomposition proceeded according to the pseudo-first and pseudo-second-order kinetic models, while the degradation of Orange II followed the zero, pseudo-first, and pseudo-second order kinetic models.

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Adsorption performance and mechanisms of mercaptans removal from gasoline oil using core-shell AC-based adsorbents: Role of intra-particles space

10.21203/rs.3.rs-326696/v1 ◽

2021 ◽

Author(s):

Pamphile Ndagijimana ◽

Xuejiao Liu ◽

Zhiwei Li ◽

Zhenjiao Xing ◽

Beibei Pan ◽

...

Keyword(s):

Activated Carbon ◽

Removal Efficiency ◽

Liquid Fuels ◽

Core Shell ◽

High Mechanical Strength ◽

Adsorption Behaviors ◽

Pore Texture ◽

Pseudo Second Order ◽

Granulated Activated Carbon

Abstract Sulfur compound detection such as mercaptans in liquid fuels is undesirable because sulfur is the main sourcing emission of sulfur oxide (SOx) into the air. The use of activated carbon (AC) has proven to efficiently remove mercaptans. In the meantime, it is limited by the generation of the second pollution in oil, and the difficulties of recovery and regeneration. To address these issues, a core-shell structured AC with high mechanical strength and big intra-particles space were synthesized and demonstrated to efficiently remove organic pollutants from an aqueous solution without generation of the second pollution in our previous work. However, the performance, characteristics, and mechanism of mercaptans adsorption from gasoline oil by core-shell structured AC was still unclear. In this study, the mercaptans adsorption behaviors using core-shell powdered activated carbon (CSAC) and core-shell granulated activated carbon (CSGAC), along with raw PAC, PAC-core, raw GAC, and GAC-core were carried out. The results showed that both the CSAC and CSGAC adsorbents effectively removed sulfur-based pollutants and were provided with good recovery and recyclability without second pollution in gasoline oil. The CSGAC exhibited a higher mercaptans removal efficiency compared to those of CSAC as a result of the bigger intra-particles space. PAC-based adsorbents, presented the shrinking of removal efficiency after regeneration. The Pseudo-second-order kinetics and Langmuir isotherms models were dominated for mercaptans adsorption by both CSAC and CSGAC. Furthermore, the interactions between mercaptans and the composites were probably ascribed to the Van der Waals force, hydrophobic compatibility, pore texture, and π-π dispersion interaction.

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The adsorption and Fenton behavior of iron rich Terra Rosa soil for removal of aqueous anthraquinone dye solutions: kinetic and thermodynamic studies

Water Science & Technology ◽

10.2166/wst.2017.468 ◽

2017 ◽

Vol 76 (11) ◽

pp. 3114-3125 ◽

Cited By ~ 8

Author(s):

Doga Aktas ◽

Nadir Dizge ◽

H. Cengiz Yatmaz ◽

Yasemin Caliskan ◽

Yasin Ozay ◽

...

Keyword(s):

Removal Efficiency ◽

Contact Time ◽

Oxidation Process ◽

Second Order ◽

Order Kinetic ◽

Anthraquinone Dye ◽

Thermodynamic Studies ◽

Soil Loading ◽

Pseudo Second Order ◽

The Impact

Abstract Adsorption and advanced oxidation processes are being extensively used for treatment of wastewater containing dye chemicals. In this study, the adsorption and Fenton behavior of iron rich Terra Rosa soil was investigated for the treatment of aqueous anthraquinone dye (Reactive Blue 19 (RB19)) solutions. The impact of pH, initial dye concentration, soil loading rate, contact time and temperature was systematically investigated for adsorption process. A maximum removal efficiency of dye (86.6%) was obtained at pH 2, soil loading of 10 g/L, initial dye concentration of 25 mg/L, and contact time of 120 min. Pseudo-first-order, pseudo-second-order, Elovich, and Weber–Morris kinetic models were applied to describe the adsorption mechanism and sorption kinetic followed a pseudo-second-order kinetic model. Moreover, Langmuir, Freundlich and Temkin isotherm models were used to investigate the isothermal mechanism and equilibrium data were well represented by the Langmuir equation. The maximum adsorption capacity of soil was found as 4.11 mg/g using Langmuir adsorption isotherm. The effect of soil loading and hydrogen peroxide (H2O2) dosage was solely tested for Fenton oxidation process. The highest removal efficiency of dye (89.4%) was obtained at pH 2, H2O2 dosage of 10 mM, soil loading of 5 g/L, initial dye concentration of 50 mg/L, and contact time of 60 min. Thermodynamic studies showed that when the adsorption dosage of dye was 25 mg/L at 293–313 K, adsorption enthalpy (ΔH) and entropy (ΔS) were negative and adsorption free energy (ΔG) was positive. This result indicated that the adsorption was exothermic. Morphological characteristics of the soil were evaluated by X-ray fluorescence (XRF), scanning electron microscopy (SEM), and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy before and after the adsorption and oxidation process.

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Preparation and Methylene Blue Adsorption Characteristics of Highly Mesoporous Rice Husk Active Carbon Prepared by an Alkali-Saving and Equipment-Friendly Method

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.448-453.182 ◽

2013 ◽

Vol 448-453 ◽

pp. 182-187 ◽

Cited By ~ 1

Author(s):

Da Wei Li ◽

Xi Feng Zhu

Keyword(s):

Methylene Blue ◽

Removal Efficiency ◽

Rice Husk ◽

Active Carbon ◽

Dye Removal ◽

Order Kinetic ◽

Mesopore Volume ◽

Order Kinetic Model ◽

Naoh Solution ◽

Pseudo Second Order

Highly mesoporous active carbon for removing methylene blue (MB) from aqueous solution was prepared from pyrolyzed rice husk by combination of CO2activation and NaOH-solution boiling. The preparation method was found to be alkali-saving and equipment-friendly. The prepared active carbon exhibited high mesoporosity (79.1%), with mesopore volume and specific surface area up to 0.619 mL/g and 899 m2/g, respectively. At initial MB concentrations of 240-380 mg/L, the MB removal efficiency of the prepared active carbon ranged from 92% to more than 99%, fairly comparable to that of the highly mesoporous commercial active carbon used for reference. The adsorption of MB onto the prepared active carbon well followed the pseudo second-order kinetic model and Langmuir isotherm. This study indicated that highly mesoporous active carbon with large dye removal efficiency could be prepared from rice husk by an alkali-saving and equipment-friendly process.

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Optimizing modified rice bran for treating aqueous solutions polluted by Cr (VI) ions: isotherm and kinetics analyses

Quality Assurance and Safety of Crops & Foods ◽

10.15586/qas.v13isp1.942 ◽

2021 ◽

Vol 13 (SP1) ◽

pp. 1-11

Author(s):

Zahra Ameri ◽

Mehran Hoodaji ◽

Majid Rajaei ◽

Mitra Ataabadi

Keyword(s):

Removal Efficiency ◽

Rice Bran ◽

Freundlich Isotherm ◽

Contact Duration ◽

Isotherm Equation ◽

Chemically Modified ◽

Ph Values ◽

Chromium Vi ◽

Pseudo Second Order ◽

Modified Adsorbents

This study investigated the possibility and efficiency of absorbing chromium (VI) (Cr [VI]) ions from the polluted solutions by employing the chemically modified adsorbents (alkali, biochar, and acid rice bran), focusing on the possible impacts of the solution’s pH values, adsorbent’s dosages, concentrations, and contact times. The colori-metric method was used for Cr determination by employing an ultraviolet/visible spectrophotometer. The scanning electron microscope and Fourier transform infrared spectroscopy were used to analyze the characteristics of the modified adsorbents. The findings indicated that the optimized acid, biochar, alkali, and unmodified rice bran removal efficiency for Cr (VI) were 94.50%, 94.27%, 88.60%, and 90.18%, respectively. The increase of adsorbent dosage up to 2 g/L led to a rise in removal effectiveness (82.06%). Furthermore, the highest removal efficiency was obtained (94%) at the pH of 2.0, the contact duration of 100 min, Cr (VI) concentration of 50 mg/L, and dosage of 2 g/L, which was statistically the optimal condition for the modified rice bran. The adsorption kinetics was agreeably suited to pseudo-second-order, whereas the Freundlich isotherm equation was also suitably expounded the study’s findings. The findings implied that the acid and biochar rice bran performed remarkably in the reme-diation of the wastewater compared with alkali rice bran for reuse for industrial, agricultural, and environmental purposes.

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Modelling of the adsorption of chlorinated phenols on polyethylene and polyethylene terephthalate microplastic

Journal of the Serbian Chemical Society ◽

10.2298/jsc190712124l ◽

2020 ◽

Vol 85 (5) ◽

pp. 697-709

Author(s):

Maja Loncarski ◽

Aleksandra Tubic ◽

Marijana Kragulj-Isakovski ◽

Branislav Jovic ◽

Tamara Apostolovic ◽

...

Keyword(s):

Polyethylene Terephthalate ◽

Hydrophobic Interactions ◽

Sorption Process ◽

Aquatic Environments ◽

Order Kinetic ◽

Chlorinated Phenols ◽

Adsorption Affinity ◽

Order Kinetic Model ◽

Pseudo Second Order

The role of microplastics (MPs) on the fate and transport of various pollutants in water matrices is of major concern, but it is still relatively under investigated. In order to consider the conditions in real aquatic environments, the changes to polyethylene (PE) structure during the fabrication of microplastic particles for specific uses should not be neglected. Thus, this work considers isolated PE from two types of personal care products, which are possible sources of microplastic contamination in aquatic environments. The adsorption affinity of these PE microplastics towards ionisable compounds was compared with those of standards of PE and polyethylene terephthalate (PET), using chlorinated phenols (4-chlorophenol, 2,4-dichlorophenol, 2,4,6-trichlorophenol and pentachlorophenol) as adsorbates. The pseudo-second order kinetic model described well the sorption process for all chlorinated phenols on all four types of MPs (R2 range: 0.900?0.998). The kinetic study showed that sorption rates are mainly controlled by hydrophobic interactions and molecule size. Adsorption isotherms were best described by the Freundlich model for all MPs. The obtained results indicate that MPs could serve for the transport of chlorinated phenols through ambient waters.

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Adsorptive Removal and Recovery of Aluminium (III), Iron (II), and Chromium (VI) onto a Low Cost Functionalized Phragmities Karka Waste

Journal of Institute of Science and Technology ◽

10.3126/jist.v20i2.13969 ◽

2015 ◽

Vol 20 (2) ◽

pp. 145-152

Author(s):

Shukraraj Regmi ◽

Kedar Nath Ghimire ◽

Megh Raj Pokhrel ◽

Deba Bahadur Khadka

Keyword(s):

Adsorption Process ◽

Low Cost ◽

Volume Ratio ◽

Freundlich Isotherm ◽

Loading Capacity ◽

Order Kinetic ◽

Chemically Modified ◽

Chromium Vi ◽

Pseudo Second Order ◽

Concentrated Sulfuric Acid

Chemically modified adsorbent based on Phragmities stem has been investigated by treating with concentrated sulfuric acid at 2:1 weight/volume ratio. The maximum loading capacity for Al(III) and Fe(II) onto phosphorylated charred Phragmities waste PCPW adsorbent was found to be 148 mg/g and 200 mg/g, while for Cr(VI) 200 mg/g, respectively, at their optimal pH. Similarly, it was 166.66 mg/g and 90.90mg/g for Al(III) and Fe(II) onto the charred Phragmities waste CPW, respectively. The adsorption process followed the Freundlich isotherm and pseudo-second order kinetic models. The desorption of the loaded metal ions recovery was found to be to the extent of 82%, 91% and 100% for Al(III), Fe(II) and Cr(VI), respectively.Journal of Institute of Science and Technology, 2015, 20(2): 145-152

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Methylene Blue Adsorption onto Cockle Shells-Treated Banana Pith: Optimization, Isotherm, Kinetic, and Thermodynamic Studies

Indonesian Journal of Chemistry ◽

10.22146/ijc.42822 ◽

2020 ◽

Vol 20 (2) ◽

pp. 368

Author(s):

Rosalyza Hasan ◽

Wong Jie Ying ◽

Chong Chi Cheng ◽

Nur Farhana Jaafar ◽

Rohayu Jusoh ◽

...

Keyword(s):

Methylene Blue ◽

Low Cost ◽

Alkaline Treatment ◽

Order Kinetic ◽

Positive Role ◽

Independent Variables ◽

Initial Ph ◽

Pseudo Second Order ◽

Kinetic And Thermodynamic Studies

Two low-cost wastes, banana pith (BP) and cockle shells (CS) were explored towards methylene blue (MB) removal. The performance of cockle shells-treated banana pith (CS-BP) in MB removal was compared with untreated BP and commercially Ca(OH)2-treated BP (Ca(OH)2-BP). The adsorption efficacy was following the order of BP < CS-BP < Ca(OH)2-BP, indicating the positive role of alkaline treatment towards MB removal and great potential of CS as a low-cost activation material. The optimization of MB removal onto CS-BP was executed by response surface methodology (RSM) with three independent variables (adsorbent dosage (X1), initial pH (X2) and initial MB concentration (X3)), and the optimal condition was achieved at X1 = 1.17 g/L, X2 = pH 7 and X3 = 214 mg/L, with 87.32% of predicted MB removal. The experimental data well-fitted the pseudo-second-order kinetic (R2 > 0.99) and the Langmuir isotherm (R2 = 0.999) models, demonstrating the chemisorption and naturally homogeneous process. Thermodynamics study discovered that the MB removal by CS-BP is endothermic, feasible, spontaneous and randomness growth at a solid-solute interface. It is affirmed that CS could be employed as a low-cost activation material and CS-BP as a low-cost adsorbent.

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