scholarly journals Investigation of Nickel Ion Removal by Means of Activated Clay

1992 ◽  
Vol 9 (4) ◽  
pp. 244-257 ◽  
Author(s):  
S. Hawash ◽  
J.Y. Farah ◽  
M.S. El-Geundi

Natural and activated clays have been investigated as adsorbents for the removal of nickel from wastewater. Analysis of the natural clay under test showed that it was composed, approximately of 51% kaolinite, 46% montmorillonite and 3% illite, having a specific surface area of 65 m2/g. The natural clay was treated with different activators (HCl, NaCl and H2O2) to enhance its adsorption capacity towards nickel. The efficiency of such activation was greater by 16.0% and 23.2% in the case of NaCl and H2O2, respectively, relative to untreated clay. No significant increase in the adsorption capacity was brought about by HCl treatment. A limited comparison has been made between clay and activated carbon by performing isotherm studies under similar conditions. The results indicate that the adsorption capacity of clay activated with H2O2, clay activated with NaCl and natural clay is 216.9%, 204.2% and 176.1% that of activated carbon, respectively. Based solely on the adsorption capacity, an economic analysis demonstrates that natural clay is the cheapest material, followed by clay activated with NaCl and clay activated with H2O2. The relative costs of removing nickel using natural clay, clay activated with NaCl and clay activated with H2O2 were found to be 2.8%, 5.4% and 25.4%, respectively, that of activated carbon.

2021 ◽  
Vol 15 (2) ◽  
pp. 131-144
Author(s):  
Chunjiang Jin ◽  
Huimin Chen ◽  
Luyuan Wang ◽  
Xingxing Cheng ◽  
Donghai An ◽  
...  

In this study, aspen wood sawdust was used as the raw material, and Fe(NO3)3 and CO2 were used as activators. Activated carbon powder (ACP) was produced by the one-step physicochemical activation method in an open vacuum tube furnace. The effects of different mass ratios of Fe(NO3)3 and aspen wood sawdust on the pore structure of ACP were examined under single-variable experimental conditions. The mass ratio was 0–0.4. The detailed characteristics of ACP were examined by nitrogen adsorption, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The adsorption capacity of ACP was established by simulating volatile organic compounds (VOCs) using ethyl acetate. The results showed that ACP has a good nanostructure with a large pore volume, specific surface area, and surface functional groups. The pore volume and specific surface area of Fe-AC-0.3 were 0.26 cm3/g and 455.36 m2/g, respectively. The activator played an important role in the formation of the pore structure and morphology of ACP. When the mass ratio was 0–0.3, the porosity increased linearly, but when it was higher than 0.3, the porosity decreased. For example, the pore volume and specific surface area of Fe-AC-0.4 reached 0.24 cm3/g and 430.87 m2/g, respectively. ACP presented good VOC adsorption performance. The Fe-AC-0.3 sample, which contained the most micropore structures, presented the best adsorption capacity for ethyl acetate at 712.58 mg/g. Under the action of the specific reaction products nitrogen dioxide (NO2) and oxygen, the surface of modified ACP samples showed different rich C/O/N surface functional groups, including C-H, C=C, C=O, C-O-C, and C-N.


2014 ◽  
Vol 976 ◽  
pp. 207-211 ◽  
Author(s):  
Alejandra Alicia Peláez Cid ◽  
Araceli Vázquez Barranco ◽  
Ana María Herrera González

This paper presents the results of the adsorption of textile dyes in static systems, using adsorbent materials prepared from broccoli waste collected after harvest. The adsorption capacities of the non-activated lignocellulosic residue (BrocNat), the chemically activated waste using sodium hydroxide (BrocNaOH), the thermally activated at 823 K ash (AshBroc), and the chemically activated carbon using phosphoric acid at 673 K (CarBrocQ) were tested. Aqueous solutions containing cationic and anionic dyes as well as textile effluents generated after the dyeing process of a cotton-processing factory containing vat and reactive dyes were treated. Lignocellulosic materials were only effective in removing dyes when they were found in aqueous solution. The carbonaceous adsorbent CarBrocQ presented removal percentages close to 100% and between 13 and 75% for reactive and vat dyes contained in the effluents respectively. To accomplish the complete elimination of color from effluents containing vat dyes, these were treated before adsorption, using aluminum chlorohydrate and poly(acrylamide-co-sodium acrylate) as coagulant and flocculant agents, respectively. The COD of the effluent containing vat dyes was reduced up to 93% after both treatments were combined, and the removal of color was absolute. The high adsorption capacity of CarBrocQ occurs because of its high specific surface area, which was determined by N2 adsorption to be 1177 m2g-1. In the case of the lignocellulosic material, the specific surface area was determined by means of adsorption of methylene blue, and it was 485 m2g-1 for both. The adsorption capacity of CarBrocQ was compared with that of commercial carbons, and proved to be similar. The adsorption results obtained indicate that broccoli waste can be used to prepare activated carbon with applications in the removal of dyes present in textile effluents.


2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Hoang Thu Ha ◽  
Pham Tuan Phong ◽  
Tran Dinh Minh

This work reveals the As(V) adsorption behaviors onto iron oxide (Fe3O4) nanoparticles modified activated carbon (AC), originally developed from biochar (BC), as a green adsorbent denoted by FAC. Since FAC has abundant surface functional groups and a desired porous structure that is favorable for the removal of As(V) in contaminated water, FAC has greatly enhanced the As(V) adsorption capacity of the original BC. Various methods were employed to characterize the FAC characteristics and adsorption mechanism, including pHpzc determination, BET specific surface area, elemental analysis (EA), and scanning electron microscopy (SEM). Results show that the AC surface was successfully modified by iron oxide nanoparticles, enhancing the porosity and specific surface area of original adsorbent. Batch adsorption tests indicated a well-fitted Langmuir model and pseudo-second-order model for As(V) adsorption. Additionally, the highest adsorption capacity (Qmax = 32.57 mg/g) by FAC was higher than previously reported literature reviews. Until now, no article was conducted to research the effect of carbon surface chemistry and texture on As removal from waters. It is required to obtain a rational view of optimal conditions to remove As from contaminated water.


2014 ◽  
Vol 2 (2) ◽  
pp. 216
Author(s):  
Baiq Asma Nufida ◽  
Nova Kurnia ◽  
Yeti Kurniasih

This research was aimed to get the effect of particel size of activated natural clay from Tanak Awu to their adsorption capacity for increase reused cooking oil quality. At previous research we done the activation of natural clay using acid (HCl) and got an optimal concentration of acid at 1 molar. Natural clay was grinding until particel size at 50 mesh, 60 mesh and 100 mesh then it was characterized in specific surface area by methylen blue methods and also acidity surface by acid base titration. Then activated natural clay was applied for purifying reused cooking oil by analyzing water content, acid number and peroxide number. The result showed that there are the effect of particel size of natural clay to acidity surface and specific surface area. While the adsorption capacity of natural clay on purifying reused cooking oil got that optimal particel size of activated natural clay at 60 mesh which getting the decrease of water content, acid number and peroxide number by following reach was 89,13%, 58,61% and 60,52%.


2021 ◽  
Author(s):  
Xiaoxia Ren ◽  
Changming Zhang ◽  
Lifang Kou ◽  
Rongxian Wang ◽  
Yaqi Wang ◽  
...  

Abstract Activated carbon spheres with high specific surface area and hierarcal porous texture were prepared from polystyrene-based macroreticular resin spheres by air pre-oxidization and steam activation. The as-prepared carbon spheres had a specific surface area of 1274.95 m2 g− 1, total pore volume of 1.09 cm3 g− 1 and micropore volume of 0.47 cm3 g− 1. Moreover, these carbon spheres showed a hierarcal porous texture composed of ultrafine micropores (0.5-1 nm), micropores (1–2 nm), mesopores (10–50 nm) and macropores (50–100 nm). A CO2 adsorption capacity of 2.82 mmol g− 1 for carbon spheres can be obtained at 30 ℃ and 1 atm. Further, after introducing nitrogen-containing functional groups by gaseous ammonia at 600 ℃, these carbon spheres exhibited a high CO2 adsorption capacity of 3.2 mmol g− 1. In addition, excellent cyclic stability, low hygroscopicity and regenerability temperature suggested these carbon spheres were favorable for CO2 capture.


2021 ◽  
Vol 2 ◽  
pp. 21-32
Author(s):  
Ju.V. Таmarkina ◽  
I.B. Frolova ◽  
O.O. Velichko ◽  
V.O. Кucherenko

The aim of the work is to evaluate the adsorption capacity of activated carbons (ACs) from brown coal in relation to phenol (Ph) and 4-chlorophenol (CPh) and the influence of the AСs formation temperature under carbonization with potassium hydroxide on capacities. The samples of ACs were prepared by heating with KOH (1 g/g, 1 h) at a given temperature in the range of t=400-800°C and marked as AC(t). The ACs porosity characteristics were determined by low-temperature (77 K) adsorption – desorption nitrogen isotherms (Micromeritics ASAP 2020) calculated by the 2D-NLDFT method. They are as follows: total pore volume Vt (cm3 /g), specific surface area S (m2 /g), volume (Vmi) and surface (Smi) of micropores, volume (V1nm) and surface (S1nm) of subnanopores, the total surface of meso- and macropores Sme+ma. The adsorption of phenol and 4-chlorophenol was determined at equilibrium concentrations in aqueous solutions ≤5 mmol/l (25 °C). The alkaline carbonization temperature of brown coal was found to be a key factor in the formation of micro- and subnanopores, the growth of the AC specific surface area (from 12.8 m2 /g to 1142 m2 /g) and adsorption activity against phenolic compounds. Its increase to 800°C causes an exponential increase in the AC adsorption capacity in 8.7 times (Ph) and 6.7 times (CPh), which is proportional to the concentration of surface adsorption centers (AdCs). The values of the effective activation energy of forming AdCs being active in relation to adsorbates were determined as 29.5 kJ/mol (Ph) and 31.5 kJ/mol (CPh). The kinetics of Ph and CPh absorption was found to obey the pseudosecond-order model, and the adsorption rate is limited by the interaction of the adsorbate molecules with the AdCs. Adsorption isotherms at equilibrium concentrations ≤ 5 mmol/l are approximated by the Langmuir model (R2 ≥ 0.994). Compared with Ph, the degree of CPh extraction is much higher, which is a consequence of its stronger connection with the AC surface. The specific adsorption capacity for Ph and CPh shows a sharp decrease (10-16 times) with increasing carbonization temperature from 400° C to 550 °C and a weak temperature dependence at 550-800 °C. In this range, ACs are formed with similar concentrations of AdCs, but different for various phenolic compounds. Adsorption on brown coal ACs was postulated to include π-π interaction, formation of electron-donor-acceptor complexes and formation of hydrogen bonds, but their contributions depend on adsorbate nature and they change while increasing alkaline carbonization temperature. Keywords: brown coal, alkaline carbonization, activated carbon, porosity, adsorption, phenol, 4-chlorophenol. Corresponding author Таmarkina Ju.V., e-mail: [email protected]


Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3811
Author(s):  
Zhongbao Liu ◽  
Jiayang Gao ◽  
Xin Qi ◽  
Zhi Zhao ◽  
Han Sun

In this study, the hydrothermal method was used to synthesize MIL-101(Cr), and activated carbon (AC) with different content was incorporated in to MIL-101(Cr), thereby obtaining AC-MIL-101(Cr) composite material with a huge specific surface area. The physical properties of MIL-101(Cr) and AC-MIL-101(Cr) were characterized by powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), thermogravimetric analysis (TGA), nitrogen adsorption and desorption and specific surface area testing, and ethanol vapor adsorption performance testing. The results show that with the increase of activated carbon content, the thermal stability of AC-MIL-101(Cr) is improved. Compared with the pure sample, the BET specific surface area and pore volume of AC-MIL-101(Cr) have increased; In the relative pressure range of 0–0.4, the saturated adsorption capacity of AC-MIL-101(Cr) to ethanol vapor decreases slightly. It is lower than MIL-101(Cr), but its adsorption rate is improved. Therefore, AC-MIL-101(Cr)/ethanol vapor has a good application prospect in adsorption refrigeration systems. The exploration of AC-MIL-101(Cr) composite materials in this paper provides a reference for the future application of carbon-based/MOFS composite adsorbent/ethanol vapor working fluid in adsorption refrigeration.


2015 ◽  
Vol 749 ◽  
pp. 17-21 ◽  
Author(s):  
Joanna Sreńscek Nazzal ◽  
Karolina Glonek ◽  
Jacek Młodzik ◽  
Urszula Narkiewicz ◽  
Antoni W. Morawski ◽  
...  

Microporous carbons prepared from commercial activated carbon WG12 by KOH and/or ZnCl2 treatment were examined as adsorbents for CO2 capture. The micropore volume and specific surface area of the resulting carbons varied from 0.52 cm3/g (1374 m2/g) to 0.70 cm3/g (1800 m2/g), respectively. The obtained microporous carbon materials showed high CO2 adsorption capacities at 40 bar pressure reaching 16.4 mmol/g.


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