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

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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Ultrasound and microwave-assisted preparation of Fe-activated carbon as an effective low-cost adsorbent for dyes wastewater treatment

RSC Advances ◽

10.1039/c6ra14082c ◽

2016 ◽

Vol 6 (82) ◽

pp. 78936-78946 ◽

Cited By ~ 24

Author(s):

Song Cheng ◽

Libo Zhang ◽

Hongying Xia ◽

Jinhui Peng ◽

Jianhua Shu ◽

...

Keyword(s):

Wastewater Treatment ◽

Activated Carbon ◽

Adsorption Capacity ◽

Removal Efficiency ◽

Langmuir Isotherm ◽

Low Cost ◽

Order Model ◽

Microwave Assisted ◽

Pseudo Second Order ◽

Mb Adsorption

A and B are Langmuir isotherm and pseudo-second-order model. We conclude that MB adsorption capacity of Fe-activated carbon is bigger than raw activated carbon, indicating that Fe-activated carbon has better MB removal efficiency.

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Trichoderma Biomass as an Alternative for Removal of Congo Red and Malachite Green Industrial Dyes

Applied Sciences ◽

10.3390/app11010448 ◽

2021 ◽

Vol 11 (1) ◽

pp. 448

Author(s):

Rosalba Argumedo-Delira ◽

Mario J. Gómez-Martínez ◽

Ramiro Uribe-Kaffure

Keyword(s):

Activated Carbon ◽

Malachite Green ◽

Removal Efficiency ◽

Congo Red ◽

Fungal Biomass ◽

Cost Effective ◽

Fresh Biomass ◽

Pseudo Second Order ◽

Cost Effective Alternative ◽

Adsorption Rates

The present study evaluated the removal efficiency of two dyes, Congo red (CR) and malachite green (MG), using either fresh or dry fungal biomass of two species of Trichoderma (T. virens and T. viride) and activated carbon. After 24 h, the CR removal efficiency obtained with fresh biomass was higher than that obtained with activated carbon. For the MG dye, the average removal with activated carbon (99%) was higher than those obtained with dry and fresh biomass of T. viride and T. virens. Experimental results for fresh and dry fungal biomass showed a good correlation with Langmuir isotherms. The adsorption rates of CR and MG by of T. virens and T. viride can be more appropriately described using the pseudo-second-order rate. We found an adsorption capacity of 81.82 mg g−1 for T. virens with MG dye. Results show that fresh or dry biomass of T. virens can represent a simple and cost-effective alternative for removing industrial dyes such as CR and MG.

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Response surface methodology as a statistical tool for optimization of removal of chromium (VI) from aqueous solution by Teff (Eragrostis teff) husk activated carbon

Applied Water Science ◽

10.1007/s13201-019-1120-8 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 1

Author(s):

Tsegaye Adane ◽

Daniel Haile ◽

Awrajaw Dessie ◽

Yohannes Abebe ◽

Henok Dagne

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Removal Efficiency ◽

Carbon Adsorbent ◽

Statistical Tool ◽

Chromium Vi ◽

Environment Exposure ◽

Column Adsorption ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

AbstractRecently, rapid industrialization leads to excessive release of heavy metals such as Cr(VI) in the environment. Exposure to chromium (VI) can cause kidney and liver damage, depressed immune systems, and a variety of cancers. Therefore, treatment of Cr(VI) containing wastewater is mandatory. This study aims to optimize the removal of Cr(VI) from aqueous solution using locally available Teff husk activated carbon adsorbent. The laboratory-based study was conducted on the optimization of Cr(VI) removal efficiency of Teff husk activated carbon from aqueous solution. A central composite design was used to examine the effect of the interaction of process parameters and to optimize the process using Design Expert version 7.0 software. The optimized removal efficiency of Teff husk activated carbon (95.597%) was achieved at 1.92 pH, 87.83 mg/L initial concentration, 20.22 g/L adsorbent dose, and 2.07 H contact time. The adsorption of Cr(VI) on Teff husk activated carbon was found to be best fitted with pseudo-second-order kinetics and Langmuir isotherm model of the adsorption. Teff husk activated carbon can be used as an efficient adsorbent for removal of chromium (VI) from contaminated water. Column adsorption needs to be studied in the future.

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Investigating the role of the morphology of the Zn-Al LDH on the adsorption of humic acid from aqueous solutions

Water Science & Technology ◽

10.2166/wst.2021.373 ◽

2021 ◽

Author(s):

Hamid Khoshalhan Davoudli ◽

Solmaz Saadat ◽

Mansour Rahsepar ◽

Fatemeh Azadi

Keyword(s):

Humic Acid ◽

Natural Water ◽

Adsorption Mechanisms ◽

Removal Capacity ◽

Adsorption Behaviors ◽

Pseudo Second Order ◽

Highly Correlated ◽

Double Hydroxides ◽

Background Ions

Abstract Flake Zn-Al layered double hydroxides (FLDHs) and microspheres of LDH (MLDHs) were fabricated with a simple hydrothermal method to investigate the role of the morphology of Zn-Al LDH for the humic acid (HA) adsorption from synthetic solutions and natural water. The effect of process variables i.e. contact time, initial concentration of HA, pH, and competitive ions on the adsorption was investigated. HA removal mechanism was also studied. The two adsorbents exhibited different adsorption behaviors for HA in the presence and absence of background ions, which may be highly correlated with the various adsorption mechanisms involved. Comparison of the HA removal capacity of these two adsorbents implies the superior adsorption capability of FLDH for removal of HA from synthetic solutions (9.5 mg/g), while the adsorption capacity of MLDH was higher for natural organic matters present in natural water samples containing co-existing ions (8.9 mg/g). The pseudo-second-order kinetics model and Longmuir isotherm model could adequately interpret the HA adsorption process for the studied adsorbents. Both LDHs exhibited good regeneration and recycling abilities.

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

Minerals ◽

10.3390/min11101108 ◽

2021 ◽

Vol 11 (10) ◽

pp. 1108

Author(s):

Xiaoqin Nie ◽

Faqin Dong ◽

Mingxue Liu ◽

Wencai Cheng ◽

Congcong Ding ◽

...

Keyword(s):

Removal Efficiency ◽

Deinococcus Radiodurans ◽

Lipid Fraction ◽

Lipid Extraction ◽

Order Kinetic ◽

Oh Groups ◽

Chemical Treatments ◽

Chemically Modified ◽

Pseudo Second Order

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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Mercury (II) adsorption from aqueous solution using nitrogen and sulfur co-doped activated carbon

Water Science & Technology ◽

10.2166/wst.2018.117 ◽

2018 ◽

Vol 2017 (1) ◽

pp. 310-318 ◽

Cited By ~ 7

Author(s):

Hangdao Qin ◽

Rong Xiao ◽

Lei Guo ◽

Jianling Meng ◽

Jing Chen

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Photoelectron Spectroscopy ◽

Point Of Zero Charge ◽

Adsorption Behaviors ◽

Pseudo Second Order ◽

Adsorption Desorption ◽

Initial Cycle ◽

Co Doped

Abstract Activated carbon (AC) was modified with urea, thioglycolic acid and thiourea to obtain nitrogen doped activated carbon (ACN), sulfur doped activated carbon (ACS) and nitrogen and sulfur co-doped activated carbon (ACNS), respectively. The AC samples were characterized by elemental analysis, N2 adsorption-desorption, determination of the pH of the point of zero charge (pHpzc) and X-ray photoelectron spectroscopy, and tested for adsorption behaviors of Hg(II) ions. The experimental data of equilibrium isotherms fitted well with the Langmuir model. ACNS showed the highest adsorption capacity of 511.78 mg/g, increasing more than 2.5 times compared to the original ACA. The adsorption process followed pseudo-second-order kinetics. The thermodynamic parameters of ΔH°, ΔS°, and ΔG° at 30 °C were −20.57 kJ/mol, −0.032 kJ/mol K and −10.87 kJ/mol, respectively. It was concluded that the Hg(II) ions' adsorption on ACNS was exothermic, spontaneous and physiosorptive in nature. Finally, the adsorption capacity of ACNS reduced by just 8.13% even after the sixth cycle compared to the initial cycle.

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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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