scholarly journals Removal of Chromium(VI) from Aqueous Solution using a Strong base Anion Exchange Resin : Kinetic and Equilibrium Studies

Author(s):  
HARISH NAGESH REVANKAR ◽  
PRASANNA S KOUJALAGI ◽  
VIJAYENDRA R GURJAR ◽  
RAVIRAJ M KULKARNI

Abstract The removal of chromium (VI) from aqueous solution using the strong base anion exchange resin Tulsion A-62 (MP) is reported in this study under a variety of experimental conditions, including initial chromium (VI) concentration, contact time, and medium pH. The ion-exchange process for the resin Tulsion A-62 (MP) was relatively simple and after 300 minutes of phase contact, the equilibrium was achieved. The sorption process, which is pH based, extracted the most chromium (VI) when the pH was between 4.0 and 5.0. Both Langmuir and Freundlich adsorption isotherms were used to fit the equilibrium results for Cr(VI) adsorption, however Langmuir isotherm model was found to be more acceptable for the Cr(VI) adsorption and maximum adsorption capacity of Cr(VI) was found to be 201.6 mg/g. Scanning Electron Microscopy with EDX and Fourier transformed infrared spectroscopy were also used to characterize Tulsion A-62 (MP) before and after chromium adsorption. The adsorption mechanism followed reversible first-order kinetics. The findings showed that such anion-exchange resins can be used to effectively extract chromium (VI) ions from water and wastewater.

2015 ◽  
Vol 5 (1) ◽  
pp. 11
Author(s):  
Anies Mutiari ◽  
Wiratni Wiratni ◽  
Aswati Mindaryani

Pemurnian biogas telah banyak dilakukan untuk menghilangkan kadar CO2  dan meningkatkan kandungan CH4  yang terkandung di dalamnya. Kandungan CH4 yang tinggi akan memberikan unjuk kerja yang lebih baik. Model  matematis proses adsorpsi CO2 disusun berdasarkan teori lapisan film antar fasa, dimana pada proses yang ditinjau terdapat tiga fase yaitu gas, cair dan padat. Model matematis dari data eksperimental   kecepatan dan kesetimbangan proses adsorpsi CO2 melalui mekanisme pertukaran ion di suatu kolom adsorpsi telah dibuat. Model ini dibuat untuk mencari konstanta yang dapat dipergunakan pada proses scale up data laboratorium ke skala pilot plant. Parameter proses kecepatan yang dicari nilainya adalah koefisien transfer massa massa volumetris CO2 pada fase cair (kLa), koefisien transfer massa volumetris CO2 pada fasegas (kGa) dan tetapan laju reaksi (k1 dan k2). Pada hasil penelitian ini ditunjukkan bahwa nilai parameter yang diperoleh sesuai hasil fitting data dengan model matematis yang digunakan, yaitu model transfer massa pada lapisan film antar fase secara seri: adalah kGa, kla, k1 dan k2  dengan nilai Sum of Squares Error (SSE) rata-rata 0,0431. Perbandingan nilai kGa hasil simulasi dan teoritisnya memberikan kesalahan rata-rata 18,79%. Perbandingan nilai kLa hasil simulasi dan teoritis memberikan kesalahan rata-rata 7,92%.Kata kunci: model matematis, adsorpsi CO2, pemurnian biogas


Author(s):  
György Pátzay ◽  
József Dobor ◽  
Emil Csonka ◽  
Gábor Lozsi ◽  
Ferenc Feil

Borate ion exchange capacity of Purolite NRW600 strong base anion resin in hydroxide form and mixed bed NRW600+NRW100 ion exchange was investigated with static experiments. Anion exchange resin was saturated with 0.1–45 g/dm3 concentration boric acid solution in a static mixer at 20, 30, 40 and 50 °C at 150 rpm for 24 hours. Remaining borate content of saturation solutions was deter-mined with ion chromatography and ICP-OES. The amount of fixed borate as borate anions increased with the saturation borate concentration as well as in case of simple anion exchange as in case of mixed bed.Column sorption-elution study was carried out by using strong base anion exchange resins (Purolite NRW600 and Amberlite IRN78). Resins in hydroxide and in chloride forms were saturated in column with 5–40 g/dm3 boric acid solution in excess. The resin was then eluted with 200 cm3 salt free water with 5 cm3/min at 25 °C and then eluted by 1 mol/dm3 sodium-sulfate solution with 5 cm3/min. The effluent was collected and analyzed for borate content by titrimetric method. In chloride form the resin adsorbed and released much less borate. Effective borate and polyborate sorption needs hydroxide ions in resin phase.


Processes ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 404 ◽  
Author(s):  
Jiangnan Yu ◽  
Jialin Liao ◽  
Zhenxing Huang ◽  
Peng Wu ◽  
Mingxing Zhao ◽  
...  

The bioproduction of caproate from organic waste by anaerobic mixed culture is a very attractive technology for upgrading low-grade biomass to a high-value resource. However, the caproate production process is markedly restricted by the feedback inhibition of caproate. In this study, four types of anion-exchange resin were investigated for their enhancing capability in caproate fermentation of anaerobic mixed culture. The strong base anion-exchange resin D201 showed the highest adsorption capacity (62 mg/g), selectivity (7.50), and desorption efficiency (88.2%) for caproate among the test resins. Subsequently, the optimal desorption temperature and NaOH concentration of eluent for D201 were determined. The adsorption and desorption efficiency of D201 remained stable during eight rounds of the adsorption–desorption cycle, indicating a satisfactory reusability of D201. Finally, performances of caproate fermentation with and without resin adsorption for carboxylate were evaluated. The results demonstrated that the final concentration of caproate was improved from 12.43 ± 0.29 g/L (without adsorption) to 17.30 ± 0.13 g/L (with adsorption) and the maximum caproate production rate was improved from 0.60 ± 0.01 g/L/d to 2.03 ± 0.02 g/L/d. In the group with adsorption, the cumulative caproate production was increased to 29.10 ± 0.33 g/L broth, which was 134% higher than that of the control group. Therefore, this study provides effective approaches to enhance caproate production.


1985 ◽  
Vol 38 (4) ◽  
pp. 633 ◽  
Author(s):  
IW Stapleton

A simple procedure for the large-scale purification of commercial polyethyleneamines (H2N[CH2CH2NH]nH where n = 2-5) is described in which the per- tosylate salt separates as a crystalline solid from aqueous solution. The salts require no further purification except for pentaethylenehexamine (n = 5), which requires recrystallization from water. The free bases are regenerated from the tosylate salt by an anion-exchange resin.


2020 ◽  
Vol 326 (1) ◽  
pp. 445-454
Author(s):  
Fuping Liu ◽  
Rong Hua ◽  
Feng Zhang ◽  
Heng Liu ◽  
Chuan-Pin Lee ◽  
...  

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