scholarly journals Grafting of Chloroacetic Acid on EGDE Cross-Linked Chitosan to Enhance Stability and Adsorption Capacity For Pb(II) Ions

2014 ◽  
Vol 14 (1) ◽  
pp. 63-70 ◽  
Author(s):  
Abu Masykur ◽  
Sri Juari Santosa ◽  
Dwi Siswanta ◽  
Jumina Jumina

The aims of this research is to synthesize a chitosan derivative insoluble in acidic aqueous medium and that has high adsorption capacity for Pb(II) ions by cross-linking and grafting. Cross-linking and grafting were done using ethylene glycol diglycidyl ether (EGDE) and chloroacetic acid, respectively. The modified chitosan was characterized using FTIR spectrophotometer, XRD and TG-DTA. Chitosan and Chit-EGDE-Acetate was applied as adsorbent of Pb(II) ions in a batch system. The concentration of Pb(II) in adsorption medium was quantified using AAS. The result showed that the adsorption was optimum at pH 5, contact time of 200 min for chitosan and 300 min for Chit-EGDE-Acetate. Adsorption of Pb(II) ions on both adsorbents followed pseudo second order kinetic equation. Adsorption of Pb(II) ions on chitosan followed Freundlich isotherm while that on Chit-EGDE-Acetate followed the Langmuir adsorption isotherm. The adsorption capacity of Chit-EGDE-Acetate for Pb(II) ions was 200.0 mg L-1 while that for chitosan was 166.7 mg L-1. Interaction type of Pb(II) ions on adsorbent was determined by sequential desorption.

2014 ◽  
Vol 14 (2) ◽  
pp. 152-159 ◽  
Author(s):  
Abu Masykur ◽  
Sri Juari Santosa ◽  
Dwi Siswanta ◽  
Jumina Jumina

The aims of this research is to synthesize Pb(II) imprinted polymers with carboxymethyl chitosan (CMC) as polymers and bisphenol A diglycidyl ether (BADGE) as cross-linker (Pb-IIP). Chitosan (CTS), non imprinted polymer (NIP) and Pb-IIP were characterized using infrared (IR) spectroscopy, X-ray diffraction (XRD), surface area analyzer (SAA), scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) spectroscopy. The result showed that the adsorption was optimum at pH 5 and contact time of 250 min. Adsorption of Pb(II) ion with all of adsorbents followed pseudo-second order kinetic equation. Adsorption of Pb(II) ion on CTS followed Freundlich isotherm while that on NIP and Pb-IIP followed the Langmuir adsorption isotherm. The adsorbent of Pb-IIP give higher capacity than the NIP and CTS. Adsorption capacity of Pb-IIP, NIP and CTS were 167.1, 128.9 and 76.1 mg/g, respectively. NIP gave higher adsorption selectivity for Pb(II)/Ni(II) and Pb(II)/Cu(II), whereas Pb-IIP showed higher adsorption selectivity for Pb(II)/Cd(II).The hydrogen bonding dominated interaction between Pb(II) ion on NIP and Pb-IIP.


2010 ◽  
Vol 5 (1) ◽  
Author(s):  
Hülya Karaca ◽  
Turgay Tay ◽  
Merih Kıvanç

The biosorption of lead ions (Pb2+) onto lyophilized fungus Aspergillus niveus was investigated in aqueous solutions in a batch system with respect to pH, contact time and initial concentration of the ions at 30 °C. The maximum adsorption capacity of lyophilized A. niveus was found to be 92.6 mg g−1 at pH 5.1 and the biosorption equilibrium was established about in 30 min. The adsorption capacity obtained is one of the highest value among those reported in the literature. The kinetic data were analyzed using the pseudo-first-order kinetic, pseudo-second-order kinetic, and intraparticle diffusion equations. Kinetic parameters, such as rate constants, equilibrium adsorption capacities, and related correlation coefficients for the kinetic models were calculated and discussed. It was found that the adsorption of lead ions onto lyophilized A. niveus biomass fit the pseudo-second-order kinetic model well. The Langmuir and Freundlich isotherm parameters for the lead ion adsorption were applied and the Langmuir model agreed better with the adsorption of lead ions onto lyophilized A. niveus.


SAINTIFIK ◽  
2020 ◽  
Vol 6 (2) ◽  
pp. 104-115
Author(s):  
Agusriyadin Agusriyadin

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.


2021 ◽  
Author(s):  
Mingyue Piao ◽  
Hongxue Du ◽  
Yuwei Sun ◽  
Honghui Teng

Abstract Hybrid hydrogel was synthesized by immobilizing TiO2 in polyethylene glycol diacrylate (TiO2@PEGDA) as an efficient adsorbent with photocatalysis property for bisphenol A (BPA) elimination. TiO2@PEGDA exhibited spherical and rough structure with limited crystallinity and abundant functional groups. The contact angle was 61.96°, indicating that TiO2@PEGDA is hydrophilic. The swelling capacity of TiO2@PEGDA (9.0%) was decreased compared with pristine PEGDA (15.6%). Adsorption results demonstrated that the maximum adsorption capacity of TiO2@PEGDA (101.4 mg/g) for BPA was slightly higher than pristine PEGDA (97.68 mg/g). The adsorption capacity was independent with pH at pH < 8.0, and decreased obviously when the value of pH was higher than 8.0. The adsorption behavior was fitted well with the pseudo-second-order kinetic and the Freundlich isotherm model. Both ΔG0 and ΔH0 were negative, indicating that BPA adsorbed on TiO2@PEGDA was an exothermic and spontaneous process. Regeneration study was performed by photocatalysis, and the adsorption capacity was 85.6% compared with the initial capacity after four cycles of illumination, indicating that TiO2@PEGDA could be recycled without significant loss of adsorption capacity. Consequently, TiO2@PEGDA can serve as an eco-friendly and promising material for efficiently adsorbing BPA with self-clean property.


2021 ◽  
Vol 15 (1) ◽  
pp. 1-8
Author(s):  
Angelica Macalalad ◽  
◽  
Quennie Rose Ebete ◽  
Dominic Gutierrez ◽  
Madelaine Ramos ◽  
...  

The present study is focused on the use of activated carbon derived from water hyacinth (WH-AC) as adsorbent for the removal of Cr(VI) from aqueous solution. The optimized WH-AC was found to be mesoporous and considered as granular. The surface area of 11.564 m2/g was found to have a good adsorption capacity. The adsorption data of the optimized WH-AC followed a pseudo-second order kinetics and the Freundlich isotherm model. Based on the correlation coefficient obtained from pseudo-second-order kinetic model, the R2 values were all above 0.99, which is closer to unity of one (1) indicating that it followed a chemisorption process. The adsorption capacity of WH-AC increased from 1.98 to 4.68 mg/g when adsorbate concentration increased from 20 to 50 mg/l. The overall study proved that the adsorption by activated carbon derived from water hyacinth can be an alternative and efficient technique in hexavalent chromium removal.


2018 ◽  
Vol 16 (1) ◽  
pp. 36 ◽  
Author(s):  
Idha Yulia Ikhsani ◽  
Sri Juari Santosa ◽  
Bambang Rusdiarso

Adsorption of disperse dyes from wastewater onto Ni-Zn LHS (layered hydroxide salts) and Mg-Al LDH (layered double hydroxides) has been compared in this study. Effects of initial pH solution, contact time and initial dye concentration were investigated. The ability of the adsorbent to be reused was also studied. The results showed that acidic condition was favorable for the adsorption of each dyes onto both adsorbent. The adsorption kinetics was studied using pseudo-first-order, pseudo-second-order and Santosa’s kinetics models. The experimental data fits well with the pseudo-second order kinetic model. The equilibrium adsorption data were analyzed using Langmuir and Freundlich isotherm models. The results showed that adsorption of navy blue onto both adsorbent followed Freundlich isotherm adsorption, while yellow F3G followed Langmuir isotherm adsorption. In the application for the adsorption the wastewater containing dyes, Ni-Zn LHS has a better adsorption capacity of 52.33 mg/g than that of Mg-Al LDH that 30.54 mg/g. Calcination of the adsorbent which has already been used increased the adsorption capacity of Mg-Al LDH to 84.75 mg/g, but decreased the adsorption capacity of the Ni-Zn LHS to 42.65 mg/g.


2012 ◽  
Vol 629 ◽  
pp. 358-363
Author(s):  
Xue Qing Chen ◽  
Ji Lin Cao ◽  
Tian Shui Feng ◽  
Xin Ling You

Aiming at the removal of chlorinated disinfection by-products in water and the difficulty of separation of powder bentonite from water, the polyacrylamide bentonite composite was prepared and used as absorbent. The mechanism of adsorption and regeneration was discussed. The adsorption of chloroacetic acid on polyacrylamide bentonite composite followed Langmuir isothermal and Pseudo second order kinetic equation, and the adsorption capacity was 63.01mg/g at optimal temperature 30°C. The sorption heat were at the range of 9~16kJ/mol and decreased with the increase of temperature. It was indicated the adsorption mainly belonged to chemical adsorption, and the proportion of physical adsorption increased with the temperature increase. The thermodynamic parameters were ΔH0=-5.226kJ/mol, ΔG0=-27.753kJ/mol. These showed the adsorption was spontaneous and exothermal process. The composites were characterized by XRD and FT-IR. It was found the acrylamide intercalated in interlayer of bentonite and polymerized, then interacted with bentonite by hydrogen bonds. The d001 increased and decreased with adsorption and regeneration, the chloroacetic acid was considered to intercalate in the interlayer of polyacrylamide bentonite composite. The hydrogen bonds may exist between chloroacetic acid and CH2 groups. The polyacrylamide bentonite composite adsorbed chloroacetic acid could be regenerated by NaOH solution.


2012 ◽  
Vol 550-553 ◽  
pp. 2255-2258
Author(s):  
Bing Bing Liu ◽  
Hua Yong Zhang ◽  
Lu Yi Zhang

Phosphate adsorption from aqueous solution using slag was investigated as the function of pH, contact time and adsorbent dosage. The results showed that the optimum value of pH was 2. Both Langmuir isotherm and Freundlich isotherm model were fit to describe the phosphate adsorption, and the maximum adsorption capacity from Langmuir model calculated was 9.09 mg/L. The adsorption process on slag followed pseudo second-order kinetic. Due to the relatively high adsorption capacity, the slag has the potential for application to removal phosphate from wastewater.


2021 ◽  
Vol 7 (2) ◽  
pp. 55-65
Author(s):  
Nazanin Parsa ◽  
Hassan Rezai

Today, due to the industrialization of societies, the existence of heavy metals has created many problems for humans, other organisms, and the environment. Lead (Pb) is highly toxic and the second most commonly used metal. The aim of this study was to evaluate the efficiency of melamine-modified nanographene oxide in the removal of Pb from aqueous media. To increase the efficiency of graphene oxide, it was mechanically converted to nano graphene oxide and melamine (4, 2 and 6-triazine, 3, 1 and 5 triamine). Experiments were performed at pH value of 3-8, temperature of 15-50°C, Pb concentration of 5-200 mg/g, adsorbent dose of 0.01-0.06 g, and contact time of 15- 150 minutes. The mechanism of the adsorption process was investigated using two Langmuir and Freundlich isotherm models, pseudo-first order and pseudo-second order kinetic equations, and thermodynamic equations. The results showed that the adsorption rate corresponds to the Freundlich isotherm model and pseudo-second order kinetic equation. Thermodynamic studies also showed that the adsorption process is associated with increasing irregularities and it is endothermic. In constant conditions (pH of 6, contact time of 60 minutes, ambient temperature of 22°C, Pb concentration of 20 mg/L, and adsorbent dose of 0.01 g), the adsorption capacity was 191.65 mg/g. The highest adsorption occurs at the concentration of 5 mg/L and the highest adsorption capacity and removal percentage was observed at a concentration of 200 mg/L, which were 1896.3 mg/g and 98.8%, respectively. Due to the high adsorption capacity, the adsorbent was able to remove lead from the contaminated environment.


Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4318
Author(s):  
Elie Meez ◽  
Abbas Rahdar ◽  
George Z. Kyzas

The threat of the accumulation of heavy metals in wastewater is increasing, due to their abilities to inflict damage to human health, especially in the past decade. The world’s environmental agencies are trying to issue several regulations that allow the management and control of random disposals of heavy metals. Scientific studies have heavily focused on finding suitable materials and techniques for the purification of wastewaters, but most solutions have been rejected due to cost-related issues. Several potential materials for this objective have been found and have been compared to determine the most suitable material for the purification process. Sawdust, among all the materials investigated, shows high potential and very promising results. Sawdust has been shown to have a good structure suitable for water purification processes. Parameters affecting the adsorption mechanism of heavy metals into sawdust have been studied and it has been shown that pH, contact time and several other parameters could play a major role in improving the adsorption process. The adsorption was found to follow the Langmuir or Freundlich isotherm and a pseudo second-order kinetic model, meaning that the type of adsorption was a chemisorption. Sawdust has major advantages to be considered and is one of the most promising materials to solve the wastewater problem.


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