scholarly journals Facile Synthesis of Polyethylene Glycol@Tannin-Amine Microsphere towards Cr(VI) Removal

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1035
Author(s):  
Chengbing Yuan ◽  
Yan Zhang ◽  
Jinshui Yao ◽  
Qinze Liu ◽  
Fan-Gong Kong
Keyword(s):  
Polyethylene Glycol ◽  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Sewage Treatment ◽  
Maximum Adsorption Capacity ◽  
Hydroxyl Groups ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Synthetic Strategy ◽  
Order Kinetic Model

Herein, a synthetic strategy for a rough microsphere Cr(VI)-adsorbent via the reaction of tannic acid (TA) and 1,6-hexanediamine (HA) and using polyethylene glycol (PEG) as surface modifier was presented. This adsorbent was characterized by a Fourier Transform Infrared spectrometer (FTIR), thermogravimetic analysis (TGA), X-ray photoelectron spectroscopy (XPS), etc. Certain factors, including contact time, PEG@poly(tannin-1,6-hexanediamine) (PEG@PTHA) dosage, initial concentration, and experimental temperature affecting the Cr(VI) adsorption performance of adsorbent were explored. PEG@PTHA can adsorb Cr and the Cr(VI) was reduced up to Cr(III) due to the existence of phenolic hydroxyl groups. Its adsorption capacity can reach up to 300 mg/g within 10 min and approximately 100% removal percentage below the initial concentration of 100 mg/L. Its behavior matched well with the Langmuir isotherm model and pseudo-second-order kinetic model. A PEG@PTHA adsorbent with maximum adsorption capacity (450 mg/g) has great prospects in Cr(VI)-sewage treatment.

scholarly journals Adsorptive removal of phosphate by a Fe–Mn–La tri-metal composite sorbent: Adsorption capacity, influence factors, and mechanism

2020 ◽  
Vol 38 (7-8) ◽  
pp. 254-270
Author(s):  
Yuanrong Zhu ◽  
Xianming Yue ◽  
Fazhi Xie
Keyword(s):  
Aqueous Solutions ◽  
Adsorption Capacity ◽  
Photoelectron Spectroscopy ◽  
Phosphate Removal ◽  
Maximum Adsorption Capacity ◽  
Hydroxyl Groups ◽  
Metal Composite ◽  
Order Kinetic ◽  
Composite Sorbent ◽  
Composite Adsorbent

Reducing input of phosphorus is the key step for control of eutrophication and algal blooming in freshwater lakes. Adsorption technology is a cost-effective technology for phosphate removal in water for the purpose. Thus, in this study, a novel Fe–Mn–La tri-metal composite sorbent was developed, and then evaluated for phosphate removal. The results showed that the maximum adsorption capacity could be approached to 61.80 mg g−1 at 25°C under pH of 6.03. Adsorption of phosphate by Fe–Mn–La tri-metal composite adsorbent fitted better by pseudo-second-order kinetic equation and Langmuir model, which suggested that the adsorption process was surface chemical reactions and mainly in a monolayer coverage manner. The thermodynamic study indicated that the adsorption reaction was an endothermic process. The phosphate removal gradually decreased with the increasing of pH from 3.02 to 11.00. The sequence of coexisting anions competing with phosphates was that CO32− > Cl− > SO42− > NO3−. Dissolved organic matter, fulvic acid as a representative, would also decrease adsorption capacities of phosphate by Fe–Mn–La tri-metal composite adsorbents. Adsorption capacity would be decreased with increasing addition of adsorbents, while removal efficiency would be increased in this process. The Fe–Mn–La tri-metal composite adsorbent showed a good reusability when applied to removal of dissolved phosphate from aqueous solutions. The Fourier transform infrared spectrometer and X-ray photoelectron spectroscopy analyses indicated that some hydroxyl groups (–OH) on the surface of adsorbent were replaced by the adsorbed PO43−, HPO42−, or H2PO4−. Aggregative results showed that the novel Fe–Mn–La tri-mental composite sorbent is a very promising adsorbent for the removal of phosphate from aqueous solutions.

scholarly journals Rapid Adsorption Removal of Triclosan and p-chloro-m-xylenol In Water By Nitrogen Doped Magnetic Porous Carbon

2021 ◽  
Author(s):  
Qiuxing Li ◽  
Li Huang ◽  
Paijin Zhu ◽  
Min Zhong ◽  
Shuxia Xu
Keyword(s):  
Adsorption Capacity ◽  
Porous Carbon ◽  
Photoelectron Spectroscopy ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
One Pot ◽  
X Ray ◽  
Order Kinetic Model ◽  
Endothermic Process ◽  
The One

Abstract Contamination of water resources with organic substances like phenolic fungicides is undesirable due to the improvement of living standards, huge production and consumption of daily chemicals, and an increase in the population. In this study, ZIF-67(Co) was synthesized using the “one pot method”, and the Co-magnetic porous carbon (Co-NPC) was prepared by ZIF-67 (Co) carbonization in an atmosphere of N2. The materials were tested using a X-ray diffractometer (XRD), scanning electron microscope (SEM), infrared spectroscopy (IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), N2 adsorption-desorption and magnetization analysis. These methods indicated that the Co-NPC was successfully prepared. With the original morphology of ZIF-67 (Co) crystal, the Co-NPC also has good porosity, magnetic properties and a large specific surface area. In water, Co-NPC-800 has a good adsorption capacity for triclosan (TCS) and p-chloro-m-xylenol (PCMX), which are kinds of aromatic fungicides. The adsorption of Co-NPC-800 on both reached equilibrium within 3 min, which is in accordance with the quasi-second-order kinetic model. At 298 K, the maximum adsorption capacity of Co-NPC-800 for TCS and PCMX was 163 and 39 mg·g-1, respectively. The adsorption of TCS and PCMX by Co-NPC-800 is a spontaneous endothermic process with reduced entropy. The combination of Co-NPC-800 and phenols come from multiple action of electrostatic, π-π and hydrogen bond effects. Moreover, Co-NPC-800 can be regenerated through simple washing and can be reused several times. Therefore, Co-NPC-800 has great potential to be applied across sewage treatments and other environmental fields.

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

SAINTIFIK ◽  
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.

Preparation of Graphene Oxide Modified Rice Husk for Cr(VI) Removal

2019 ◽  
Vol 19 (11) ◽  
pp. 7035-7043 ◽  
Author(s):  
Tong Ouyang ◽  
Jidan Tang ◽  
Fang Liu ◽  
Chang-Tang Chang
Keyword(s):  
Graphene Oxide ◽  
Adsorption Capacity ◽  
Rice Husk ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Adsorption Sites ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Alkaline Conditions ◽  
Rice Husk Biochar

The objective of this paper is to study the removal of Cr(VI) in aqueous solution by using a new graphene oxide-coated rice husk biochar composite (GO-RHB). GO-RHB is a synthetic material having a porous structure with lots of oxygen-containing functional groups and a large surface area that provide effective adsorption sites. Experiments showed that GO-RHB had higher adsorption capacity under acidic than under alkaline conditions. At pH of 2, GO-RHB has the maximum adsorption capacity(48.8 mg g−1). Equilibrium data obtained by fitting with the Langmuir and Freundlich models indicate that the reaction process was monolayer adsorption. The adsorption of Cr(VI) followed the pseudo-second-order kinetic model that illustrates chemical adsorption. Intraparticlediffusion studies further revealed that film diffusion was taking place. Moreover, the results of thermodynamics showed that the adsorption process was endothermic and spontaneous in nature. The removal mechanism of Cr(VI) was also explained in detail. The prepared adsorbent is highly efficient and might be useful than many other conventional adsorbent used for the removal of Cr(VI) from wastewater.

scholarly journals SURFACE MODIFICATION OF CANARIUM OVATUMENGL.(PILI) SHELL AS ADSORBENT OF LEAD(Pb2+) FROM AQUEOUS SOLUTION

2021 ◽  
Author(s):  
Ernesto Jr. S. Cajucom ◽  
◽  
Lolibeth V. Figueroa ◽  
Keyword(s):  
Aqueous Solution ◽  
Adsorption Capacity ◽  
Freundlich Isotherm ◽  
Cost Effective ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Carboxylic Groups ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
Surface Modified

This study was carried out to investigate the efficiency of raw pili shell (RPS) and the surface modified pili shell using EDTA (EMPS) and oxalic acid (OMPS). A comparative study on the adsorption capacity of the adsorbents was performed against lead (Pb2+) from aqueous solution. The adsorbents were characterized by FTIR, which showed higher peak of adsorption bands of carboxylic groups on the acid modified pili shells. Scanning electron microscope orSEM was also used to describe the surface morphology of the adsorbents. The linear form of Langmuir and Freundlich models were applied to represent adsorption data. The calculated equilibrium data of Pb (II) best fitted to Langmuir compare to Freundlich isotherm model with maximum adsorption capacity (qmax) of 27.03 mg/g and 45.45 mg/g using EMPS and OMPS, respectively. Kinetic sorption models were used to determine the adsorption mechanism and the kinetic data of all the adsorbents correlated (R2=1) wellwith the pseudo second order kinetic model. Among the three adsorbents, OMPS shown higher percent removal of lead compared to RPS and EMPS. The large adsorption capacity rate indicated that chemically modified pili shell in present study has great potential to be used as a cost-effective adsorbent for the removal of lead ions from the water.

scholarly journals Sheet-like Skeleton Carbon Derived from Shaddock Peels with Hierarchically Porous Structures for Ultra-Fast Removal of Methylene Blue

Water ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 2554
Author(s):  
Panlong Dong ◽  
Hailin Liu ◽  
Shengrui Xu ◽  
Changpo Chen ◽  
Suling Feng ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Surface Area ◽  
Adsorption Process ◽  
Batch Adsorption ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Initial Concentration ◽  
Hierarchically Porous ◽  
Column Adsorption

To remove the pollutant methylene blue (MB) from water, a sheet-like skeleton carbon derived from shaddock peels (SPACs) was prepared by NaOH activation followed by a calcination procedure under nitrogen protection in this study. Characterization results demonstrated that the as-prepared SPACs displayed a hierarchically porous structure assembled with a thin sheet-like carbon layer, and the surface area of SPAC-8 (activated by 8 g NaOH) was up to 782.2 m2/g. The as-prepared carbon material presented an ultra-fast and efficient adsorption capacity towards MB due to its macro-mesoporous structure, high surface area, and abundant functional groups. SPAC-8 showed ultrafast and efficient removal capacity for MB dye. Adsorption equilibrium was reached within 1 min with a removal efficiency of 99.6% at an initial concentration of 100 mg/g under batch adsorption model conditions. The maximum adsorption capacity for MB was up to 432.5 mg/g. A pseudo-second-order kinetic model and a Langmuir isotherm model described the adsorption process well, which suggested that adsorption rate depended on chemisorption and the adsorption process was controlled by a monolayer adsorption, respectively. Furthermore, column adsorption experiments showed that 96.58% of MB was removed after passing through a SPAC-8 packed column with a flow rate of 20 mL/min, initial concentration of 50 mg/L, and adsorbent dosage of 5 mg. The as-prepared adsorbent displays potential value in practical applications for dye removal due to its ultrafast and efficient adsorption capacity.

Investigation of Modified Mangrove Bark on the Sorption of Oil in Water

2014 ◽  
Vol 567 ◽  
pp. 74-79 ◽  
Author(s):  
Asadpour Robabeh ◽  
Nasiman Sapari ◽  
Mohamed Hasnain Isa ◽  
Kalu Uka Orji
Keyword(s):  
Palmitic Acid ◽  
Adsorption Capacity ◽  
Sorption Capacity ◽  
Oil Spills ◽  
Low Cost ◽  
Correlation Coefficients ◽  
Kinetic Studies ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Order Kinetic Model

Today oil spills generally cause worldwide worry due to their damaging effects on environment. Use of agricultural wastes such as raw and modified mangrove barks (RhizophoraApiculata), as an abundant and low cost adsorbent for oil-products spill cleanup in aquatic systems, has been developed to control these spills. Sorption capacity can improve by modification of adsorbent. The modification significantly increased the hydrophobicity of the adsorbent. The raw mangrove bark was modified using fatty acid (Palmitic acid) to improve its adsorption capacity. Oil sorption capacity of the modified bark was studied and compared with the raw bark. Kinetic tests were conducted with a series of contact time. The kinetic studies show good correlation coefficients for a pseudo-first-order kinetic model. A correlation between surface functional groups of the adsorbent was studied by FTIR spectrum. The results gave the maximum adsorption capacity of 2640.00 ± 2.00 mg/g for Palmitic acid treated bark (PTB). The prepared adsorbent revealed the potential to use as a low-cost adsorbent in oil-spill clean-up.

scholarly journals Steel slag as low-cost adsorbent for the removal of phenanthrene and naphthalene

2018 ◽  
Vol 36 (3-4) ◽  
pp. 1160-1177 ◽  
Author(s):  
Liyun Yang ◽  
Xiaoming Qian ◽  
Zhi Wang ◽  
Yuan Li ◽  
Hao Bai ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Low Cost ◽  
Steel Slag ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Batch Experiments ◽  
Obvious Effect ◽  
X Ray ◽  
Order Kinetic Model ◽  
Langmuir Isotherm Model

This study investigates the removal effectiveness and characteristics of phenanthrene and naphthalene using low-cost steel slag with batch experiments. The adsorption characteristics of steel slag were measured and analysed using X-ray fluorescence, X-ray diffraction, and Fourier transform infrared spectroscopy. The batch experiments investigated the effect of the time gradient, pH, and steel slag dosage gradient on the adsorption of the steel slag. The results show that with time and dosage of steel slag increased, the adsorption capacity of phenanthrene and naphthalene increased and gradually became balanced, but pH had no obvious effect on the adsorption of phenanthrene and naphthalene. The Langmuir isotherm model best describes the phenanthrene and naphthalene removal by the steel slag, which shows the adsorption occurring in a monolayer. The maximum adsorption capacity of the steel slag to phenanthrene and naphthalene is 0.043 and 0.041 mg/g, respectively. A pseudo-first-order kinetic model can better represent the adsorption of phenanthrene and naphthalene by steel slag. The research demonstrates that the steel slag has a certain adsorption capacity for phenanthrene and naphthalene.

scholarly journals Modified Vermiculite as Adsorbent of Hexavalent Chromium in Aqueous Solution

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 749
Author(s):  
Celia Marcos ◽  
Valeria Medoro ◽  
Alaa Adawy
Keyword(s):  
Adsorption Capacity ◽  
Adsorption Energy ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Ion Chemistry ◽  
Solution Ph ◽  
Cooperative Process ◽  
Order Kinetic Model ◽  
Initial Adsorption ◽  
Initial Adsorption Rate

The aim of this study was to investigate the efficiency of removing Cr6+ from aqueous solutions using two exfoliated vermiculite: (1) heated abruptly at 1000 °C and (2) irradiated with microwave radiation. The effects investigated were contact time, adsorbate concentration and initial Cr6+ concentration. The adsorption with both exfoliated vermiculites was well described by the DKR isotherm, indicative of a cooperative process and with the pseudo second order kinetic model. The Kd value for the two exfoliated vermiculites was similar, 0.2 ·1010 μg/Kg. The maximum adsorption capacity of Cr6+ with thermo-exfoliated vermiculite, 2.81 mol/g, was much higher than with microwave irradiated vermiculite, 0.001 mol/g; both values were obtained with 0.5 g of vermiculite in contact with distilled water enriched with 1 ppm of Cr6+ for 24 h. Factors such as ion chemistry, the solution pH and ionic strength, influence the values of capacity, adsorption energy and initial adsorption rate values of the exfoliated vermiculite. In addition, these values depended on the exfoliation process, being the adsorption capacity highest with abrupt heating of vermiculite, while the adsorption energy and rate values showed just a slight increase with microwave irradiation. This aspect is important to select the most suitable vermiculite modification treatment to use it as an adsorbent.

Adsorption of methylene blue by using novel chitosan-g-itaconic acid/bentonite nanocomposite – equilibrium and kinetic study

2017 ◽  
Vol 75 (8) ◽  
pp. 1932-1943 ◽  
Author(s):  
Farzaneh Shakib ◽  
Ahmad Dadvand Koohi ◽  
Arash Kamran Pirzaman
Keyword(s):  
Methylene Blue ◽  
Adsorption Capacity ◽  
Itaconic Acid ◽  
Maximum Adsorption Capacity ◽  
Order Kinetic ◽  
Oh Groups ◽  
Maximum Sorption ◽  
Equilibrium Data ◽  
Order Kinetic Model ◽  
The Fourier Transform

In this study, novel chitosan-g-itaconic acid/bentonite (CTS-g-IA/BT) and chitosan/bentonite (CTS/BT) nanocomposites were synthesized for adsorption of methylene blue (MB) from aqueous solution. The process was pH-sensitive and maximum sorption was obtained at pH 6 (CTS-g-IA/BT) and 7 (CTS/BT) in 76 h agitation time using 0.03 g of nanocomposites for 50 mL of MB solution. The results showed that in pH less than 6, the adsorption capacity of CTS-g-IA/BT nanocomposite due to the existence of IA monomer is less than that of CTS/BT nanocomposite. The Fourier transform infrared spectroscopy (FTIR) spectrum of CTS-g-IA/BT revealed that both itaconic acid and BT present in the nanocomposite structure, and also the –OH groups of BT, –NH2 and –OH of CTS participated in nanocomposite formation. According to the FTIR results, a schematic diagram of the nanocomposite synthesis was presented. The kinetic results indicated that the adsorption of MB fitted well with the pseudo-second-order kinetic model. The equilibrium data followed Langmuir isotherm with the maximum adsorption capacity of 500 and 181.818 mg/g for CTS-g-IA/BT and CTS/BT nanocomposites, respectively. The negative values of Gibbs free energy change (ΔG0) and the positive values of ΔH0 confirmed that the adsorption process is spontaneous and endothermic. The positive values of ΔS0 suggested the randomness of adsorption at interface.

Sign in / Sign up

Export Citation Format

Share Document