Desulfurization performance of MgO/ rice straw biochar adsorbent prepared by co-precipitation/calcination route

A solid adsorbent for SO2 adsorption was prepared from magnesium salt/rice straw via co-precipitation/calcination. The effects of various preparation conditions, including the calcination temperature, the weight ratio of Mg/rice straw, magnesium salts, and amine precipitants, were investigated relative to their effects on the desulfurization performance of adsorbents. Maximum sulfur adsorption capacity (260 mg/g) was obtained with MgO/rice straw biochar adsorbent using tetraethylenepentamine (TEPA) as the precipitants, and the preparation conditions included a calcination temperature of 400 °C, a Mg/rice straw weight ratio of 1.2, and magnesium chloride hexahydrate (MgCl2·6H2O) as the magnesium source. The rice straw biochar-supported MgO sample displayed a high SO2 adsorption capacity due to its excellent textural properties, large specific surface areas, small crystallite size, numerous surface active sites of MgO nanoparticles, and introduced N-H groups. The physical and chemical properties of samples were investigated by field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller (BET) analyses, Fourier transform infrared spectrometer (FT-IR), elemental analysis (EA), and X-ray diffraction (XRD).

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Removal of Cr (III) Ions from Wastewater using Sawdust and Rice Husk Biochar Pyrolyzed at Low Temperature

International Journal for Innovation Education and Research ◽

10.31686/ijier.vol4.iss4.531 ◽

2016 ◽

Vol 4 (4) ◽

pp. 44-54 ◽

Cited By ~ 1

Author(s):

Sunethra Kanthi Gunatilake

Keyword(s):

Functional Groups ◽

Rice Straw ◽

Active Sites ◽

Adsorption Sites ◽

Saw Dust ◽

Optimum Ph ◽

Intra Particle Diffusion ◽

Rice Straw Biochar ◽

Rice Husk Biochar ◽

Complexation Mechanism

Sorption capacity of two different biochar (saw dust and rice straw) was evaluated in the recovery of chromium from wastewater. The optimum pH was 5-7 for recovery of Cr(III). Optimum yield was received after 1 hour contacting time with an adsorbent dose of 1 g/L and initial concentration was ∼20 mg/L. Cr(III) ions were transported to biochar surface through adsorption and intra-particle diffusion process. Langmuir and Freundlich kinetic parameters indicated that the affinity of the sorbent towards the uptake of Cr(III) ions and adsorptions were favorable. According to FTIR analysis of Cr(III) ions bound to active sites either electrostatic attraction or complexation mechanism. These results indicated that carbonyl, hydroxyl, amine and halides are the main adsorption sites in saw dust and rice straw biochar and these functional groups complexes with Cr(III) ions in the aqueous solution and changed the chemical environment of the functional groups in the biochar.

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Rice Straw Biochar and Magnetic Rice Straw Biochar for Safranin O Adsorption from Aqueous Solution

Water ◽

10.3390/w14020186 ◽

2022 ◽

Vol 14 (2) ◽

pp. 186

Author(s):

Do Thi My Phuong ◽

Nguyen Xuan Loc

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Rice Straw ◽

Batch Adsorption ◽

Particle Diffusion ◽

Order Kinetic ◽

Magnetic Biochar ◽

Intra Particle Diffusion ◽

Rice Straw Biochar ◽

Safranin O

This study investigates the adsorption of Safranin O (SO) from aqueous solution by both biochar and magnetic biochar derived from rice straw. Rice straw biochar (RSB) was made by pyrolysis in a furnace at 500 °C, using a heating rate of 10 °C·min−1 for 2 h in an oxygen-limited environment, whilst the magnetic rice straw biochar (MRSB) was produced via the chemical precipitation of Fe2+ and Fe3+. The physicochemical properties of the synthesized biochars were characterized using SEM, SEM- EDX, XRD, FTIR techniques, and N2 adsorption (77 K) and pHpzc measurements. Batch adsorption experiments were used to explore the effect of pH, biochar dosage, kinetics, and isotherms on the adsorption of SO. Experimental data of RSB and MRSB fit well into both Langmuir and Freundlich isotherm models, and were also well-explained by the Lagergren pseudo-second-order kinetic model. The maximum SO adsorption capacity of MRSB was found to be 41.59 mg/g, while for RSB the figure was 31.06 mg/g. The intra-particle diffusion model indicated that the intra-particle diffusion may not be the only rate-limiting step. The collective physical and chemical forces account for the adsorption mechanism of SO molecules by both RSB and MRSB adsorbents. The obtained results demonstrated that the magnetic biochar can partially enhance the SO adsorption capacity of its precursor biochar and also be easily separated from the solution by using an external magnet.

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Effects of Preparation Conditions and Environmental Conditions on Rice-straw-biochar Adsorption of Urea

DEStech Transactions on Engineering and Technology Research ◽

10.12783/dtetr/apetc2017/11415 ◽

2017 ◽

Cited By ~ 1

Author(s):

Zhao Haitao ◽

Han Shuwen ◽

Li Tianpeng ◽

Yao Xu ◽

Li Zongyu ◽

...

Keyword(s):

Rice Straw ◽

Environmental Conditions ◽

Preparation Conditions ◽

Rice Straw Biochar

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Operating Conditions and Composition Effect on the Hydrogenation of Carbon Dioxide Performed over CuO/ZnO/Al2O3 Catalysts

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.14.3.3451.604-613 ◽

2019 ◽

Vol 14 (3) ◽

pp. 604 ◽

Cited By ~ 2

Author(s):

Djaouida Allam ◽

Salem Cheknoun ◽

Smain Hocine

Keyword(s):

Carbon Dioxide ◽

Active Sites ◽

Metallic Copper ◽

Weight Ratio ◽

Hydrogenation Reaction ◽

Operating Conditions ◽

Precipitation Method ◽

X Ray Diffraction ◽

Co Precipitation ◽

Hydrogenation Of Carbon Dioxide

A series of catalysts constituted of mixed copper and zinc oxides supported on alumina were prepared by co-precipitation method. The cooper content was in the 10-90 wt.% range. Their catalytic behavior in the hydrogenation of carbon dioxide to methanol was investigated at high pressure (up to 75 bars). The catalysts were characterized by elemental analysis, N2-adsorption, N2O-chemisorptions, and X-ray diffraction (XRD). The catalysts showed a clear activity in the hydrogenation reaction that could be correlated to the surface area of the metallic copper and to the reaction pressure. The CuO/ZnO/Al2O3 catalyst with a Cu/Zn/Al weight ratio of 60/30/10, exhibits the highest carbon dioxide conversion and methanol selectivity. Finally, a mechanism pathway has been proposed on copper active sites of (Cu0/CuI) oxidation state. Copyright © 2019 BCREC Group. All rights reserved

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Analisis Variasi Temperatur Aktivasi Terhadap Daya Serap Arang Aktif Tandan Aren (Arenga Pinnata Merr) Dengan Agen Aktivasi Potassium Silicate(K2SiO3)

Jurnal Penelitian Pendidikan Fisika ◽

10.36709/jipfi.v5i3.13803 ◽

2020 ◽

Vol 5 (3) ◽

pp. 221

Author(s):

Muhammad Azam ◽

Muhammad Anas ◽

Erniwati Erniwati

Keyword(s):

Methylene Blue ◽

Activated Carbon ◽

Adsorption Capacity ◽

Temperature Variation ◽

Chemical Activation ◽

Weight Ratio ◽

Potassium Silicate ◽

Physical Activation ◽

Activation Temperature ◽

Pyrolysis Reactor

This study aims to determine the effect of variation of activation temperature of activated carbon from sugar palm bunches of chemically activatied with the activation agent of potassium silicate (K2SiO3) on the adsorption capacity of iodine and methylene blue. Activated carbon from bunches of sugar palmacquired in four steps: preparationsteps, carbonizationstepsusing the pyrolysis reactor with temperature of 300 oC - 400 oC for 8 hours and chemical activation using of potassium silicate (K2SiO3) activator in weight ratio of 2: 1 and physical activation using the electric furnace for 30 minutes with temperature variation of600 oC, 650 oC, 700 oC, 750 oC and 800 oC. The iodine and methyleneblue adsorption testedby Titrimetric method and Spectrophotometry methodrespectively. The results of the adsorption of iodine and methylene blue activated carbon from sugar palm bunches increased from 240.55 mg/g and 63.14 mg/g at a temperature of 600 oC to achieve the highest adsorption capacity of 325.80 mg/g and 73.59 mg/g at temperature of 700 oC and decreased by 257.54 mg/g and 52.03 mg/g at a temperature of 800 oCrespectively.However, it does not meet to Indonesia standard (Standard Nasional Indonesia/SNI), which is 750 mg/g and 120 mg/g respectively.

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Processing of Iridium Doped Materials and Experimental Investigation of Their Hydrogen Adsorption Capacity

Revista de Chimie ◽

10.37358/rc.18.6.6348 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1468-1472

Author(s):

Radu Mirea ◽

Mihai Iordoc ◽

Gabriela Oprina ◽

Gimi Rimbu

Keyword(s):

Adsorption Capacity ◽

Hydrogen Adsorption ◽

Weight Ratio ◽

H2 Adsorption ◽

Cyclic Voltametry ◽

Physical Chemical ◽

Good Consistency ◽

Metal Doped ◽

And Storage ◽

Poly Aniline

The paper aims to present the investigation of H2 adsorption capacity in metal doped nanostructured materials, by using two methods. Carbonic materials are considered to be one of the most promising materials to be used for hydrogen adsorption and storage. They have different applications and one of the most important is considered to be fuel cells technology. By using metals for doping these materials, the adsorption capacity increases, thus approaching the target of 6.5% weight ratio of H2 adsorbed in a substrate. Within these investigations multi-wall nanotubes and poly-aniline have been used as substrates. The poly-aniline has been prepared and doped in laboratory while the nanotubes used in experiments have been purchased from the market and afterwards doped in laboratory. The doping procedure consists of a physical-chemical method which involves salts of the metal for doping and the use of ultrasounds in order to activate the substrate for doping. The adsorption capacity of the carbonic materials has been determined by using spill over phenomena in a PCT Pro-User apparatus, provided by SETARAM and also by cyclic voltametry, by using VoltaLab-40 apparatus. In order to investigate the adsorption capacity of the nanostructured carbonic materials, the experiments have been carried out at different pressures. Both substrates have been characterized in order to determine their porosity, BET surface and structure. The collected data have been processed by using the PCT Pro-User apparatus�s software. The results have been compared with the available data from literature and a good consistency was found.

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Study on the adsorption selection of CH$$_4$$ on CuO (110) versus (111) surfaces: a density functional theory study

SN Applied Sciences ◽

10.1007/s42452-021-04386-x ◽

2021 ◽

Vol 3 (4) ◽

Author(s):

Long Lin ◽

Linwei Yao ◽

Shaofei Li ◽

Zhengguang Shi ◽

Kun Xie ◽

...

Keyword(s):

Density Functional Theory ◽

Adsorption Capacity ◽

Active Sites ◽

Density Functional ◽

Oxygen Vacancies ◽

Density Functional Theory Calculations ◽

Density Functional Theory Study ◽

Functional Theory ◽

Strong Adsorption ◽

Selection Of

AbstractFinding the active sites of suitable metal oxides is a key prerequisite for detecting CH$$_4$$ 4 . The purpose of the paper is to investigate the adsorption of CH$$_4$$ 4 on intrinsic and oxygen-vacancies CuO (111) and (110) surfaces using density functional theory calculations. The results show that CH$$_4$$ 4 has a strong adsorption energy of −0.370 to 0.391 eV at all site on the CuO (110) surface. The adsorption capacity of CH$$_4$$ 4 on CuO (111) surface is weak, ranging from −0.156 to −0.325 eV. In the surface containing oxygen vacancies, the adsorption capacity of CuO surface to CH$$_4$$ 4 is significantly stronger than that of intrinsic CuO surface. The results indicate that CuO (110) has strong adsorption and charge transfer capacity for CH$$_4$$ 4 , which may provide experimental guidance.

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Mixed Oxide Layered Double Hydroxide Materials: Synthesis, Characterization and Efficient Application for Mn2+ Removal from Synthetic Wastewater

Materials ◽

10.3390/ma13184089 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4089

Author(s):

Cristina Modrogan ◽

Simona Cǎprǎrescu ◽

Annette Madelene Dǎncilǎ ◽

Oanamari Daniela Orbuleț ◽

Eugeniu Vasile ◽

...

Keyword(s):

Adsorption Capacity ◽

Layered Double Hydroxides ◽

Synthetic Wastewater ◽

Precipitation Method ◽

Metallic Ions ◽

Materials Synthesis ◽

Experimental Conditions ◽

Edx Analysis ◽

Co Precipitation ◽

Double Hydroxides

Magnesium–aluminum (Mg-Al) and magnesium–aluminum–nickel (Mg-Al-Ni) layered double hydroxides (LDHs) were synthesized by the co-precipitation method. The adsorption process of Mn2+ from synthetic wastewater was investigated. Formation of the layered double hydroxides and adsorption of Mn2+ on both Mg-Al and Mg-Ni-Al LDHs were observed by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometry (EDX) analysis. XRD patterns for prepared LDHs presented sharp and symmetrical peaks. SEM studies revealed that Mg-Al LDH and Mg-Al-Ni LDH exhibit a non-porous structure. EDX analysis showed that the prepared LDHs present uniformly spread elements. The adsorption equilibrium on these LDHs was investigated at different experimental conditions such as: Shaking time, initial Mn2+ concentration, and temperatures (10 and 20 °C). The parameters were controlled and optimized to remove the Mn2+ from synthetic wastewater. Adsorption isotherms of Mn2+ were fitted by Langmuir and Freundlich models. The obtained results indicated that the isotherm data fitted better into the Freundlich model than the Langmuir model. Adsorption capacity of Mn2+ gradually increased with temperature. The Langmuir constant (KL) value of Mg-Al LDH (0.9529 ± 0.007 L/mg) was higher than Mg-Al-Ni LDH (0.1819 ± 0.004 L/mg), at 20 °C. The final adsorption capacity was higher for Mg-Al LDH (91.85 ± 0.087%) in comparison with Mg-Al-Ni LDH (35.97 ± 0.093%), at 20 °C. It was found that the adsorption kinetics is best described by the pseudo-second-order model. The results indicated that LDHs can be considered as a potential material for adsorption of other metallic ions from wastewater.

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