The Adsorption Behavior of Modified Peanut Shells for Cr (VI)

The adsorption of Cr(VI) by modified peanut shell has been investigated using chemical methods and IR spectrometry. The optimal condition for the adsorption of Cr(VI) by modified peanut shell is at 308 K and pH = 1.0, which gives a static saturated adsorption capacity of 14.15 mg·g-1, an apparent adsorption rate constant of k298 = 2.43 × 10-4 s-1, and an apparent adsorption activation energy of 10.58 kJ·mol-1. The adsorption follows the Langmuir and Freundlich isotherms and the liquid film diffusion is the controlling process of the adsorption. The adsorption thermodynamic parameters are ΔH = 125.58 kJ·mol-1, ΔS = 0.473 9 kJ·mol-1·K-1, ΔG = -17.81– -27.27 kJ·mol-1. Small amount of desorption is observed only at pH > 11. Adsorption mechanism of modified peanut shells for Cr(VI) was both physical adsorption and chemical adsorption of adsorbent "adsorption-oxidation and reduction processes".

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Evaluation of the Adsorption of Cr(VI) by Modified Bamboo Shells

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.361-363.709 ◽

2013 ◽

Vol 361-363 ◽

pp. 709-715

Author(s):

Xin Long Jiang ◽

Yi Hua Jiang

Keyword(s):

Activation Energy ◽

Adsorption Capacity ◽

Chemical Process ◽

Chemical Methods ◽

Ir Spectrometry ◽

Film Diffusion ◽

Freundlich Isotherms ◽

Langmuir And Freundlich Isotherms ◽

Negligible Influence ◽

Adsorption Activation Energy

The adsorption of Cr(VI) by modified Bamboo shell has been investigated using chemical methods and IR spectrometry. The optimal condition for the adsorption of Cr(VI) by modified Bamboo shell is at 298 K and pH = 1.0, which gives a static saturated adsorption capacity of 12.68 mg·g-1, an apparent adsorption rate constant of k298 = 9.56 × 10-4 s-1, and an apparent adsorption activation energy of 7.38 kJ·mol-1. The adsorption follows the Langmuir and Freundlich isotherms and the liquid film diffusion is the controlling process of the adsorption. The adsorption thermodynamic parameters are ΔH = 66.04 kJ·mol-1, ΔS = 0.2974 kJ·mol-1·K-1, ΔG = −22.58~−28.52 kJ·mol-1. The anions HPO42-, H2PO4- and SO42- have negligible influence on the adsorption capacity. Small amount of desorption is observed only at pH > 11. The adsorption of Cr(VI) by modified bamboo shell is mainly a chemical process.

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Study on Application of Water Granulated Slag in Rare-Earth Ammonia-Nitrogen Wastewater

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.183-185.1178 ◽

2011 ◽

Vol 183-185 ◽

pp. 1178-1184

Author(s):

Li Rong Chen ◽

Fei Hu Jia ◽

Xin Meng ◽

Lian Ke Zhang

Keyword(s):

Rare Earth ◽

Reaction Time ◽

Adsorption Mechanism ◽

Removal Rate ◽

Physical Adsorption ◽

Ammonia Nitrogen ◽

Chemical Adsorption ◽

Optimum Dosage ◽

Granulated Slag ◽

Isothermal Equation

This paper aims to study the technological conditions and adsorption mechanism of the rare-earth ammonia-nitrogen wastewater adsorption by unmodified water granulated slag and modified water granulated slag. The results showed that the optimum adsorption reaction time is around 60min for both of unmodified and modified slag; the optimum dosage of unmodified slag is 0.015g/mL, whereas it is 0.01g/mL for modified slag, correspondingly, the removal rate of ammonia-nitrogen could attain to (59.9±2.49) % and (79.24±1.21) % associated with unmodified slag and modified slag respectively. The ammonia-nitrogen removing process conducted by unmodified water granulated slag fits the Freundlich adsorption isothermal equation, conforming to physical adsorption. By contrast, the ammonia-nitrogen removing process accomplished by modified water granulated slag fits the Temkin adsorption isothermal equation and this process should be chemical adsorption.

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A Revisit to the Corrosion Inhibition of Aluminum in Aqueous Alkaline Solutions by Water-Soluble Alginates and Pectates as Anionic Polyelectrolyte Inhibitors

International Journal of Corrosion ◽

10.1155/2013/508596 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Refat Hassan ◽

Ishaq Zaafarany ◽

Adil Gobouri ◽

Hideo Takagi

Keyword(s):

Adsorption Mechanism ◽

Inhibition Efficiency ◽

Geometrical Structure ◽

Physical Adsorption ◽

Water Soluble ◽

Alkaline Media ◽

Alkaline Solutions ◽

Corrosion Mechanism ◽

Natural Polymer ◽

Freundlich Isotherms

The corrosion behavior of aluminum (Al) in alkaline media in presence of some natural polymer inhibitors has been reinvestigated. The inhibition action of the tested inhibitors was found to obey both Langmuir and Freundlich isotherms models. The inhibition efficiency was found to increase with increasing the inhibitors concentration and decrease with increasing the temperature, suggesting physical adsorption mechanism. Factors such as the concentration and geometrical structure of the inhibitor, concentration of the corrosive medium, and temperature affecting the corrosion rates were examined. The kinetic parameters were evaluated, and a suitable corrosion mechanism consistent with the kinetic results obtained is suggested and discussed.

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Peanut Shell for Energy: Properties and Its Potential to Respect the Environment

Sustainability ◽

10.3390/su10093254 ◽

2018 ◽

Vol 10 (9) ◽

pp. 3254 ◽

Cited By ~ 16

Author(s):

Miguel-Angel Perea-Moreno ◽

Francisco Manzano-Agugliaro ◽

Quetzalcoatl Hernandez-Escobedo ◽

Alberto-Jesus Perea-Moreno

Keyword(s):

Energy Source ◽

Prediction Models ◽

Energy Content ◽

Co2 Reduction ◽

High Energy ◽

Peanut Shell ◽

Agroindustrial Waste ◽

Solid Biofuel ◽

Peanut Shells ◽

Industrial Heating

The peanut (Arachys hypogaea) is a plant of the Fabaceae family (legumes), as are chickpeas, lentils, beans, and peas. It is originally from South America and is used mainly for culinary purposes, in confectionery products, or as a nut as well as for the production of biscuits, breads, sweets, cereals, and salads. Also, due to its high percentage of fat, peanuts are used for industrialized products such as oils, flours, inks, creams, lipsticks, etc. According to the Food and Agriculture Organization (FAO) statistical yearbook in 2016, the production of peanuts was 43,982,066 t, produced in 27,660,802 hectares. Peanuts are grown mainly in Asia, with a global production rate of 65.3%, followed by Africa with 26.2%, the Americas with 8.4%, and Oceania with 0.1%. The peanut industry is one of the main generators of agroindustrial waste (shells). This residual biomass (25–30% of the total weight) has a high energy content that is worth exploring. The main objectives of this study are, firstly, to evaluate the energy parameters of peanut shells as a possible solid biofuel applied as an energy source in residential and industrial heating installations. Secondly, different models are analysed to estimate the higher heating value (HHV) for biomass proposed by different scientists and to determine which most accurately fits the determination of this value for peanut shells. Thirdly, we evaluate the reduction in global CO2 emissions that would result from the use of peanut shells as biofuel. The obtained HHV of peanut shells (18.547 MJ/kg) is higher than other biomass sources evaluated, such as olive stones (17.884 MJ/kg) or almond shells (18.200 MJ/kg), and similar to other sources of biomass used at present for home and industrial heating applications. Different prediction models of the HHV value proposed by scientists for different types of biomass have been analysed and the one that best fits the calculation for the peanut shell has been determined. The CO2 reduction that would result from the use of peanut shells as an energy source has been evaluated in all production countries, obtaining values above 0.5 ‰ of their total emissions.

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Application of Waste Engine Oil for Improving Ilmenite Flotation Combined with Sodium Oleate Collector

Minerals ◽

10.3390/min11111242 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1242

Author(s):

Qingyao Yu ◽

Fuqiang Tian ◽

Yijun Cao ◽

Guixia Fan ◽

Haiqing Hao ◽

...

Keyword(s):

Sodium Oleate ◽

Strong Interaction ◽

Adsorption Mechanism ◽

Engine Oil ◽

Molar Ratio ◽

Chemical Adsorption ◽

Synergetic Effects ◽

Waste Engine Oil ◽

Environmentally Friendly Approach ◽

Long Chain

Collectors commonly have synergetic effects in ores flotation. In this work, a waste engine oil (WEO) was introduced as a collector to an ilmenite flotation system with sodium oleate (NaOL). The results show that the floatability of ilmenite was significantly improved by using WEO and NaOL as a combined collector. The recovery of ilmenite was enhanced from 71.26% (only NaOL) to 93.89% (WEO/NaOL combined collector) at the pH of 6.72. The optimum molar ratio of NaOL to WEO was about 2.08 to 1. The WEO and NaOL also have synergetic effects for the collection of ilmenite, because to obtain the ilmenite recovery of 53.96%, the dosage of 45 mg/L NaOL is equal to 38.56 mg/L WEO/NaOL combined collector (30 mg/L NaOL + 8.56 mg/L WEO). In other words, 15 mg/L of NaOL can be replaced by 8.56 mg/L of WEO. It is an effective way to reduce the dosage of the collector and reuse WEO. Therefore, it is a highly valuable and environmentally friendly approach for WEO reuse. WEO mainly consists of oxygen functional groups, aromatics, and long-chain hydrocarbons, especially for the RCONH2 and RCOOH, thereby forming a strong interaction on the ilmenite surface. The adsorption mechanism of waste engine oil and sodium oleate on the ilmenite surface is mainly contributed by chemical adsorption. Therefore, WEO exhibits superior synergistic power with NaOL as a combined collector. Herein, this work provided an effective collector for ilmenite flotation and a feasible approach for reducing NaOL dosage and recycling WEO.

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Corrosion and Kinetic Study of Eucalyptus camaldulensis Seeds Extract Percolated with Methanol on Aluminium Coupons in HCl

Earthline Journal of Chemical Sciences ◽

10.34198/ejcs.3120.6176 ◽

2020 ◽

pp. 61-76

Author(s):

Ishaq Yahaya Lawan ◽

Fatima Khalil Abdullah ◽

Sani Idris ◽

Shinggu D. Yamta ◽

Abdurrahman Hudu

Keyword(s):

Weight Loss ◽

Kinetic Study ◽

Adsorption Mechanism ◽

Eucalyptus Camaldulensis ◽

Aluminum Surface ◽

Chemical Adsorption ◽

Weight Loss Measurement ◽

Thermodynamic Consideration ◽

Loss Measurement ◽

Inhibitor Efficiency

This research discusses a detail optimization of Eucalyptus camaldulensis seeds extract as corrosion inhibitor for aluminum coupons in HCl using weight loss measurement and kinetic study. The result shows that the maximum inhibitor efficiency was obtained at a concentration of 2.0 (%W/V). However the highest inhibitor efficiency of 85% was obtained at 50ºC and the least inhibitor efficiency of 29% was obtained at 30ºC. Thermodynamic consideration revealed that adsorption of inhibitor of aluminum surface was exothermic and consistent with chemical adsorption mechanism.

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Removal of Methylene Blue from Aqueous Solutions by Using Nance (Byrsonima crassifolia) Seeds and Peels as Natural Biosorbents

Journal of Chemistry ◽

10.1155/2021/5556940 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Lorena Robles-Melchor ◽

Maribel Cornejo-Mazón ◽

Diana Maylet Hernández-Martínez ◽

Gustavo F. Gutiérrez-López ◽

Santiago García-Pinilla ◽

...

Keyword(s):

Methylene Blue ◽

Aqueous Solutions ◽

Driving Forces ◽

Physical Adsorption ◽

Point Of Zero Charge ◽

Transfer Coefficients ◽

Fractal Structures ◽

Free Energy Of Adsorption ◽

Freundlich Isotherms ◽

Byrsonima Crassifolia

Contamination of effluents with chemicals is a serious problem that impacts human health. Methylene blue is a cationic dye found frequently in industrial and urban sewages. In this work, dried grinded seeds and peels of nance were used as biosorbents in aqueous solutions at pH 7 and 10 (simulating urban and textile effluents) finding that Langmuir and Freundlich isotherms adequately described the sorption. Adsorption efficiencies were larger than 98% in all cases and slightly lower at pH 7 due to the closeness with the point of zero charge (pzc) of seeds and peels of nance (5.96 and 3.42, respectively). In all cases, Langmuir adsorption was favorable (RLa < 1), and Gibbs free energy of adsorption was negative indicating spontaneity, and since these values were larger than −80 but lower than 0 kJ/mol, the MB removal process was mainly due to physical interactions, a characteristic of physical adsorption. No significant differences were found amongst bulk mass transfer coefficients for the adsorption of both sorbents, indicating that both bioadsorbents had the same hydrodynamic and driving forces as well as depicted similar MB-adsorbent affinities. Interaction of MB with adsorbents was corroborated by FTIR spectroscopy, and the sorption was evidenced by scanning electron microscopy and image analysis which indicated that both adsorbents had fractal structures.

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Peanut shell hybrid sodium ion capacitor with extreme energy–power rivals lithium ion capacitors

Energy & Environmental Science ◽

10.1039/c4ee02986k ◽

2015 ◽

Vol 8 (3) ◽

pp. 941-955 ◽

Cited By ~ 499

Author(s):

Jia Ding ◽

Huanlei Wang ◽

Zhi Li ◽

Kai Cui ◽

Dimitre Karpuzov ◽

...

Keyword(s):

Lithium Ion ◽

Sodium Ion ◽

Peanut Shell ◽

Active Materials ◽

Peanut Shells

Hybrid sodium ion capacitor with the active materials in both electrodes derived from peanut shells bridges the critical battery–supercapacitor divide.

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Comparison of Co(ii) adsorption by a crosslinked carboxymethyl chitosan hydrogel and resin: behaviour and mechanism

New Journal of Chemistry ◽

10.1039/c6nj03837a ◽

2017 ◽

Vol 41 (9) ◽

pp. 3487-3497 ◽

Cited By ~ 11

Author(s):

Wenqiang Luo ◽

Zhishan Bai ◽

Yong Zhu

Keyword(s):

Adsorption Mechanism ◽

Physical Adsorption ◽

Carboxymethyl Chitosan ◽

Chitosan Hydrogel

This article studies the possible chemical and physical adsorption mechanism for Co(ii) onto the crosslinked carboxymethyl chitosan hydrogel and resin.

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