Sodium hydroxide modified rice husk for enhanced removal of copper ions

Abstract Although rice husk (RH) is a readily available, natural, heavy metal adsorbent, adsorption capacity in its natural form is insufficient for certain heavy metal ions. In this context, the study is based on enhancement of the adsorption capacity of RH for Cu(II). NaOH modified rice husk (SRH) shows higher extent of removal for Cu(II) ions than that of heated rice husk (HRH) and HNO3 modified rice husk (NRH). The extent of removal of SRH is increased with the concentration of NaOH, and the optimum NaOH concentration is 0.2 mol dm−3, used to modify rice husk for further studies. The surface area of SRH is 215 m2 g−1, which is twice as much as that of HRH according to previous studies. The sorption of Cu(II) on SRH obeys the Langmuir adsorption model, leading to the maximum adsorption capacity of 1.19 × 104 mg kg−1. Kinetics studies show that the interaction of Cu(II) with SRH obeys pseudo second order kinetics. The X-ray fluorescence spectroscopy confirms the adsorption of Cu(II) on SRH, while desorption studies confirm that Cu(II) adsorbed on SRH does not leach it back to water under normal conditions.

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Optimization of cadmium(II) adsorption onto modified and unmodified lignocellulosics (rice husk and egussi peeling)

International Journal of Basic and Applied Sciences ◽

10.14419/ijbas.v5i1.5195 ◽

2015 ◽

Vol 5 (1) ◽

pp. 45

Author(s):

Tchuifon Tchuifon Donald Raoul ◽

Nche George Ndifor-Angwafor ◽

Ngakou Sadeu Christian ◽

Kamgaing Théophile ◽

Ngomo Horace Manga ◽

...

Keyword(s):

Adsorption Capacity ◽

Rice Husk ◽

Order Kinetic ◽

Adsorption Model ◽

Batch Technique ◽

Order Kinetic Model ◽

Pseudo Second Order ◽

Adsorbed Quantity ◽

Minimal Mass ◽

Modified Adsorbents

<p>The present study is based on the adsorption of cadmium (II) ions on rice husk and egussi peeling, unmodified and modified with nitric acid in aqueous solution, using batch technique. It was carried out as a function of contact time, dosage, pH and initial concentration. The equilibrium time was achieved within 25 minutes for unmodified rice husk (Glu NT) and 20 minutes for unmodified egussi peeling (Cuc NT) with an adsorbed quantity of 13.18 mg/g. In the case of modified materials, we obtained 15 minutes for modified rice husk (Glu HNO3) and 10 minutes for modified egussi peeling (Cuc HNO3) with an adsorbed quantity of 18.77 mg/g. The maximum biosorption occurred at pH 5.5 for all biosorbents. The adsorbent mass for maximum adsorption was 0.4 g giving an adsorption capacity of 62.02 % for unmodified adsorbents. In the case of modified adsorbents, the minimal mass at which maximum adsorption occurred was 0.4 g giving an adsorption capacity of 98.33 % and 0.6 g giving an adsorption capacity of 98.33 % for modified rice husk and egussi peeling respectively. The adsorbent/adsorbate equilibrium was well described by the pseudo-second order kinetic model and by Langmuir’s and Freundlich adsorption model. This models showed that the adsorption of cadmium (II) is a chemisorption process.</p>

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Karekterisasi, Kinetika, dan Isoterm Adsorpsi Limbah Ampas Kelapa sebagai Adsorben Ion Cu(II)

SAINTIFIK ◽

10.31605/saintifik.v6i2.265 ◽

2020 ◽

Vol 6 (2) ◽

pp. 104-115

Author(s):

Agusriyadin Agusriyadin

Keyword(s):

Adsorption Capacity ◽

Ph Effect ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Optimum Conditions ◽

Langmuir Adsorption ◽

Adsorbent Surface ◽

Adsorption Data ◽

Order Kinetic Model ◽

Pseudo Second Order

Penelitian ini bertujuan untuk menguji kemampuan AK dan AKPM dalam mengadsorpsi ion Cu (II), pengaruh parameter adsorpsi dan mekanisme adsorpsi. AK dan AKP Madsorben dibuat dari residu ampas kelapa. Adsorben dikarakterisasi dengan FTIR, SEM dan EDS. Pengaruh parameter adsorpsi seperti pH awal, dosis adsorben, waktu kontak dan konsentrasi ion Cu (II) awal diperiksa untuk menentukan kondisi optimum serapan tembaga (II). Ion Cu (II) yang teradsorpsi diukur berdasarkan pada konsentrasi Ion Cu (II) sebelum dan sesudah adsorpsi menggunakan metode AAS. Hasil karakterisasi menunjukkan bahwa struktur pori dan gugus fungsi tersedia pada permukaan adsorben. Menurut percobaan efek pH, kapasitas adsorpsi maksimum dicapai pada pH 7. Waktu kontak optimal dan konsentrasi tembaga awal (II) ditemukan masing-masing pada 120 menit dan 100 mg L-1. Data eksperimental sesuai dengan model kinetik orde dua orde dua, dan Langmuir isoterm adsorpsi yang diperoleh paling sesuai dengan data adsorpsi. Kapasitas adsorpsi maksimum adsorben ditemukan menjadi 4,73 dan 6,46 mg g-1 pada kondisi optimal. The results of characterization showed that the pore structure and the functional groups were available on adsorbent surface. According to the pH effect experiments, the maximum adsorption capacity was achieved at pH 7. Optimum contact time and initial copper(II) concentration were found at 120 min and 100 mg L-1, respectively. The experimental data were comply with the pseudo-second-order kinetic model, and Langmuir adsorption isotherm obtained best fitted the adsorption data. The maximum adsorption capacity of the adsorbents was found to be 4.73 and 6.46 mg g-1 at optimum conditions.

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Sorptive removal of phenanthrene from aqueous solutions using magnetic and non-magnetic rice husk-derived biochars

Royal Society Open Science ◽

10.1098/rsos.172382 ◽

2018 ◽

Vol 5 (5) ◽

pp. 172382 ◽

Cited By ~ 7

Author(s):

Wei Guo ◽

Shujuan Wang ◽

Yunkai Wang ◽

Shaoyong Lu ◽

Yue Gao

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Functional Groups ◽

Rice Husk ◽

Maximum Adsorption Capacity ◽

Order Kinetic ◽

Adsorption Data ◽

Magnetic Modification ◽

Pseudo Second Order ◽

Rice Husk Biochar

A magnetically modified rice husk biochar (MBC) was successfully prepared by a hydrothermal method from original biochar (BC) and subsequently used to remove phenanthrene (PHE) from aqueous solutions. The porosity, specific surface area and hydrophobicity of BC were significantly improved (approx. two times) after magnetic modification. The adsorption data fitted well to pseudo-second-order kinetic and Langmuir models. Compared with BC, MBC had a faster adsorption rate and higher adsorption capacity of PHE. The adsorption equilibrium for PHE on MBC was achieved within 1.0 h. The maximum adsorption capacity of PHE on MBC was 97.6 mg g −1 based on the analysis of the Sips model, which was significantly higher than that of other sources of BCs. The adsorption mechanism of the two BCs was mainly attributed to the action of surface functional groups and π–π-conjugated reactions. The adsorption of PHE on MBC mainly occurred in the functional groups of C–O and Fe 3 O 4 , but that on BC was mainly in the functional groups of –OH, N–H, C=C and C–O.

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Nascent Rice Husk as an Adsorbent for Removing Cationic Dyes from Textile Wastewater

Applied Sciences ◽

10.3390/app10103437 ◽

2020 ◽

Vol 10 (10) ◽

pp. 3437

Author(s):

Jude Ofei Quansah ◽

Thandar Hlaing ◽

Fritz Ndumbe Lyonga ◽

Phyo Phyo Kyi ◽

Seung-Hee Hong ◽

...

Keyword(s):

Adsorption Capacity ◽

Rice Husk ◽

Textile Wastewater ◽

Cationic Dyes ◽

Adsorption Model ◽

Order Model ◽

Solution Ph ◽

Freundlich Model ◽

Langmuir Isotherm Model ◽

Pseudo Second Order

We assessed the applicability of rice husk (RH) to remove cationic dyes, i.e., methylene blue (MB) and crystal violet (CV), from water. RH thermally treated at 75 °C showed a higher adsorption capacity than that at high temperatures (300–700 °C). For a suitable CV-adsorption model, a pseudo-first-order model for MB adsorption was followed by the kinetics adsorption process; however, a pseudo-second-order model was then suggested. In the qt versus t1/2 plot, the MB line passed through the origin, but that of CV did not. The Langmuir isotherm model was better than the Freundlich model for both dye adsorptions; furthermore, the adsorption capacity for MB and CV was 24.48 mg/g and 25.46 mg/g, respectively. Thermodynamically, the adsorption of both MB and CV onto the RH was found to be spontaneous and endothermic. This adsorption increased insignificantly on increasing the solution pH from 4 to 10. With an increasing dosage of the RH, there was an increase in the removal percentages of MB and CV; however, adsorption capacity per unit mass of the RH was observed to decrease. Therefore, we conclude that utilizing RH as an available and affordable adsorbent is feasible to remove MB and CV from wastewater.

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Chromium (VI) adsorption onto activated sulfate lignin

Water Practice & Technology ◽

10.2166/wpt.2009.038 ◽

2009 ◽

Vol 4 (2) ◽

Cited By ~ 8

Author(s):

Nassima Tazrouti ◽

Moussa Amrani

Keyword(s):

Adsorption Capacity ◽

Contact Time ◽

Analytical Data ◽

Order Equation ◽

Second Order ◽

Isotherm Models ◽

Maximum Adsorption Capacity ◽

Adsorption Model ◽

Chromium Vi ◽

Pseudo Second Order

Activated lignin having surface area of 1023 m2.g-1 has been prepared from sulfate lignin that was treated by 30 % H2O2 and carbonized at 300 °C in order to test the chromium (VI) adsorption from aqueous solution. The influence of contact time, pH, initial concentration of adsorbent and adsorbate and temperature on the adsorption capacity were investigated. The maximum removal of Cr(VI) was found to be 92,36 % at pH=2 and contact time of 80 min. Optimal concentration of lignin and Cr(VI) were found to be 3.8 g.l-1 and 180 mg.l-1, respectively. The adsorption kinetics was tested pseudo-first-order and pseudo-second-order equation. The analytical data were fitted well in a pseudo-second-order equation and the rate of removal of chromium was found to speed up with increasing temperature. Activation energy for the adsorption process was found to be 18.19 Kj.mol-1. The Langmuir and Freundlich adsorption isotherm models were applied to describe the isotherm and isotherm constants for the adsorption of Cr (VI) on lignin. These constants and correlation coefficients of the isotherm models were calculated and compared. Results indicated that Cr (VI) uptake could be described by the Langmuir adsorption model. The maximum adsorption capacity (qm) of Cr (VI) on lignin was 75.75 mg.g-1 at temperature of 40°C. The dimensionless equilibrium parameter (RL) signified a favorable adsorption of Cr (VI) on lignin and was found between 0.0601 and 0.818 (0<RL<1). The thermodynamic parameters like ΔG°, ΔS° and ΔH° were calculated and it has been found that the reaction was spontaneous and endothermic in nature. This study indicates that lignin has the potential to become an effective and economical adsorbent for removal Cr (VI) from the waste water.

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Adsorptive removal of Ni2+ and Cd2+ from wastewater using a green longan hull adsorbent

Adsorption Science & Technology ◽

10.1177/0263617417722254 ◽

2017 ◽

Vol 36 (1-2) ◽

pp. 762-773 ◽

Cited By ~ 4

Author(s):

Xingmei Guo ◽

Sihan Tang ◽

Yan Song ◽

Junmin Nan

Keyword(s):

Metal Ions ◽

Adsorption Capacity ◽

Adsorption Mechanism ◽

Maximum Adsorption Capacity ◽

Adsorptive Removal ◽

Langmuir Adsorption ◽

Monolayer Adsorption ◽

Pseudo Second Order ◽

Adsorptive Mechanism ◽

Optimized Conditions

The adsorptive removal of Ni2+ and Cd2+ at concentrations of approximately 50 mg L−1 in wastewater is investigated using an agricultural adsorbent, longan hull, and the adsorptive mechanism is characterized. The maximum adsorption capacity of approximately 4.19 mg g−1 Cd2+ was obtained under the optimized conditions of room temperature, pH 5.0, and a solid-to-liquid ratio of 1:30 in approximately 15 min. For Ni2+, the maximum adsorption capacity of approximately 3.96 mg g−1 was obtained at pH 4.7 in approximately 20 min. The adsorption kinetics for both metal ions on the longan hull can be described by a pseudo second-order rate model and are well fitted to the Langmuir adsorption isotherm. The adsorption mechanism of the longan hull to Ni2+ and Cd2+ ions is shown to be a monolayer adsorption of metal ions onto the absorbent surface. Thereinto, the longan hull adsorbent contains N–H, C–H, C=O, and C=C functional groups that can form ligands when loaded with Ni2+ and Cd2+, which reduces the fluorescence of the dried longan hull material.

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ISOTHERM, KINETICS AND THERMODYNAMICS ADSORPTION STUDIES OF DYE ONTO Fe3O4-WASTE PAPER ACTIVATED CARBON COMPOSITES

Jurnal Teknologi ◽

10.11113/jurnalteknologi.v83.14991 ◽

2020 ◽

Vol 83 (1) ◽

pp. 45-55

Author(s):

Adel Fisli ◽

Rahma Dina Safitri ◽

Nurhasni Nurhasni ◽

Sari Hasnah Dewi ◽

Deswita Deswita

Keyword(s):

Methylene Blue ◽

Activated Carbon ◽

Adsorption Capacity ◽

Water Solution ◽

Waste Paper ◽

Carbon Composites ◽

Maximum Adsorption Capacity ◽

Adsorption Model ◽

Methylene Blue Adsorption ◽

Pseudo Second Order

This paper focused on the studying of adsorption properties of Fe3O4-waste paper activated carbon composites for the removal of methylene blue dyes from water. The various parameters were carried out for the adsorption test of the composites, namely; contact time, adsorbent dose, initial MB concentration, pH solution, and temperature. The adsorption of isotherm, thermodynamics and kinetic was used to determine the characteristics of methylene blue adsorption onto the prepared adsorbent. The result indicates that the optimum adsorption capacity has occurred at pH = 6 in water solution. The adsorption capacity increase as the temperature increase until at 315K (45oC). The Langmuir isotherm is more appropriate to be applied as the adsorption model with the maximum adsorption capacity (qm) value of 101 and 93 mg/g for KA HCl-Fe3O4 and KA-Fe3O4 composites, respectively. The value of adsorption thermodynamic parameters was positive for ΔH, negative for ΔGo and positive for ΔSo, meaning the process adsorptions were endothermic, feasibility and spontaneity and randomness, respectively. The pseudo-second-order model was appropriate to predict the kinetic models for methylene blue adsorption onto the composites. The obtained adsorbent composites possess high adsorption efficiency and rapid magnetic separation. They were a promising for practical wastewater treatment for dyes removal from water.

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A Study on Adsorption of Heavy Metals with Zeolite and FeS Media

Journal of Korean Society of Environmental Engineers ◽

10.4491/ksee.2020.42.7.349 ◽

2020 ◽

Vol 42 (7) ◽

pp. 349-359

Author(s):

Gimin Lee ◽

Gyuri Kim ◽

Sungkyu Choi ◽

Tae-jin Lee

Keyword(s):

Heavy Metals ◽

Heavy Metal ◽

Reaction Kinetics ◽

Adsorption Capacity ◽

Second Order ◽

Maximum Adsorption Capacity ◽

Adsorption Characteristics ◽

Removal Of Heavy Metals ◽

Pseudo Second Order ◽

Kinetics Of

Objectives:Adsorption characteristics in aqueous solution were investigated to effectively remove heavy metals by the crystallization of FeS and reaction kinetics were analyzed to compare with heavy metal adsorption characteristics of zeolite.Methods:The adsorption characteristics of each media were analyzed using Langmuir adsorption isotherm, and the adsorption reaction kinetics of heavy metals (Pb, Cu, Zn) on zeolite and FeS media were analyzed by a pseudo-first or pseudo-second order reaction kinetics.Results and Discussion:The maximum adsorption capacity of zeolite was highest in Pb, and the adsorption preference was in the order of Pb>Cu>Zn. In the case of FeS media, Cu was found to have a higher adsorption capacity than Pb or Zn, and the adsorption preference was observed to be Cu>Pb>Zn. It was found that the adsorption mechanism is based on chemical adsorption (chemisorption) because adsorption of each heavy metal onto zeolite or FeS media is more suitable for pseudo-second order kinetics.Conclusions:It was found that the removal of heavy metals through FeS media has a different pattern from zeolite, and when comparing the adsorption capacity of each media, it was found that FeS media is more effective for Zn or Cu except Pb.

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Removal of Cd(II) from water using zero valent iron/copper functionalized spent tea

Water Science & Technology ◽

10.2166/wst.2020.527 ◽

2020 ◽

Vol 82 (11) ◽

pp. 2552-2561

Author(s):

Khan Malook ◽

Hamayun Khan

Keyword(s):

Adsorption Capacity ◽

Morphological Characteristics ◽

Analytical Techniques ◽

Contaminated Water ◽

Maximum Adsorption Capacity ◽

Langmuir Adsorption ◽

A Value ◽

Adsorbate Concentration ◽

Initial Ph ◽

Pseudo Second Order

Abstract Zero valent Fe/Cu functionalized spent tea adsorbent was prepared for the decontamination of Cd(II) contaminated water. The synthesized material was characterized for structural and morphological characteristics using various analytical techniques. The material was used as adsorbent for the adsorption of Cd(II) from aqueous solutions in batch study experiments. The effect of initial pH, adsorbent dosage, contact time and adsorbate concentration was investigated. The obtained data well followed the Langmuir adsorption isotherm model and pseudo-second order rate model with maximum adsorption capacity of 89.686 mg·g−1. Based on Langmuir separation factor (R), having a value of 0.706–0.194, the adsorption process was confirmed to be favorable. The adsorbent was used in the form of a column for the sorption of Cd(II) from a running solution with satisfactory results. The spent material was regenerated and reutilized with reduction of adsorption capacity by 1.48% only. Overall, the current adsorbent can be efficiently utilized for the removal of aqueous Cd(II).

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Removal of Acid Blue 158 from Solution by Sunflower Seed Hull

ASEAN Journal of Chemical Engineering ◽

10.22146/ajche.49722 ◽

2013 ◽

Vol 13 (1) ◽

pp. 25

Author(s):

Siriwan Srisorrachatr ◽

Paranee Sriromreun

Keyword(s):

Adsorption Capacity ◽

Sulphuric Acid ◽

Sunflower Seed ◽

Heating Temperature ◽

Maximum Adsorption Capacity ◽

Adsorption Model ◽

Langmuir Adsorption ◽

Removal Capacity ◽

Seed Hull ◽

Acid Blue

The removal of Acid Blue 158, acid dye for textile dyeing, from aqueous solution by sunflower seed hull was studied. The extent of adsorption capacity was studied as a function of heating temperature, sulphuric acid treatment, adsorbent size and pH of the solution. Sunflower seed hull was heated at 200, 300 and 400oC in oxygen deficient conditioned furnace. As the results, the sunflower seed hull heated at 200oC was the best absorbent for the dye removal with the maximum value of 30.84% at pH 4. Furthermore, removal ratio of Acid Blue 158 increased when the adsorbent was treated with 2M sulphuric acid. Particle sizes examined in this study were 250-355, 710-2000 and over 2000 micrometer. It was showed that the size of adsorbent affected on the removal capacity, i.e. the removal capacity increased along with the decrease of the size of absorbent. pH of the solution was studied between 1 and 6, and it was found that the optimum pH was pH 2. At the optimum condition, the modified adsorbent showed the removal ability of about 50%. The results obtained under the conditions of pH 4, 2M H2SO4 treatment of sunflower seed hull and the size of 500-710 micrometer at room temperature, the adsorption isotherm was fitted to Langmuir adsorption model, and the maximum adsorption capacity, qm, of 18.52 mg/g and Langmuir adsorption constant, Kl, of 5.25x10-3 L/mg were obtained.

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