scholarly journals Adsorption of inorganic anionic contaminants on surfactant modified minerals

2003 ◽  
Vol 68 (11) ◽  
pp. 833-841 ◽  
Author(s):  
Aleksandra Vujakovic ◽  
Aleksandra Dakovic ◽  
Jovan Lemic ◽  
Ana Radosavljevic-Mihajlovic ◽  
Magdalena Tomasevic-Canovic
Keyword(s):  
Primary Amine ◽  
Acid Treatment ◽  
Diatomaceous Earth ◽  
Adsorption Properties ◽  
Second Step ◽  
Zeolite Surface ◽  
Anion Adsorption ◽  
Surface Active ◽  
Alkyl Ammonium ◽  
Efficient Adsorbent

Organo-mineral complexes were obtained by treatment of aluminosilicate minerals (zeolite, bentonite and diatomaceous earth) with a primary amine (oleylamine) and an alkyl ammonium salt (stearyldimethylbenzyl ammonium chloride). The modification of the zeolite surface was carried out in two steps. The first step was treatment of the zeolite with 2M HCl. This acid treatment of the zeolite increased its affinity for neutral molecules such as surface-active amines. The second step of the modification was the adsorption of oleylamine on the acid treated zeolite. Four types of organo-mineral complexes were prepared and their anion adsorption properties were compared to those of organo-zeolite. The adsorption of sulphate bichromate and dihydrogenphosphate anions on the organo-mineral complexes was investigated. The anion adsorption measurements showed that the most efficient adsorbent for anion water pollutants was the primary amine modified H+-form zeolite.

Zeolites featuring 14×12-Ring Channels with Unique Adsorption Properties

2021 ◽  
Author(s):  
Peng Wu ◽  
Shiqing Li ◽  
Lu Han ◽  
Zhonglin Zhao ◽  
Hao Xu ◽  
...  
Keyword(s):  
Acid Treatment ◽  
Adsorption Properties ◽  
Silylating Agent

The lamellar precursor PREFER was applied to develop interlayer expanded zeolite IEZ-FER(D4h) with extra-large pores through hydrothermal acid treatment-assisted molecular alkoxysilylation using 1,3,5,7-tetramethyl cyclo tetrasiloxane (D4h) as a silylating agent...

Effects of Acid and Heat Treatments on the Structure of Sepiolite and its Adsorption of Tannin

2012 ◽  
Vol 518-523 ◽  
pp. 728-731
Author(s):  
Cheng Yuan Su ◽  
Wei Guang Li ◽  
Meng Lin Chen
Keyword(s):  
Fourier Transform ◽  
Adsorption Capacity ◽  
Acid Concentration ◽  
Acid Treatment ◽  
Treatment Time ◽  
Heat Treatments ◽  
Adsorption Properties ◽  
Removal Rates ◽  
Calcined Temperature ◽  
Acid Treatments

In this paper, it was investigated the changes of structure of sepiolites under different conditions of acid treatments and heat treatments using fourier transform infrared spectroscopy(FTIR). At the same time, through the tannin adsorption experiments, it was studied the changes adsorption properties of sepiolites by acid treatments and heat treatments. The H2SO4 treatment was found to be more effective for the removal of tannin than HCl and HNO3 treatments. With increasing the acid concentration and acid treatment time of H2SO4, the removal rates and adsorption capacity of tannin by sepiolites were first increased and then decreased. The removal rates and adsorption capacity were 61.0% and 23.7mg/g when the acid concentration was 4.0mol/l. And the removal rates and adsorption capacity were 62.5% and 24.3mg/g when the acid treatment time was 16 hours. The calcinations treatment exhibited significant effects on the adsorption of tannin. The removal rates and adsorption capacity were 77.9% and 30.8mg/g when the calcined temperature was 400°C. However, when the calcined temperature was 700°C, the removal rates and adsorption capacity were only 54.1% and 20.8mg/g.

scholarly journals Pharmaceuticals Removal by Adsorption with Montmorillonite Nanoclay

2021 ◽  
Vol 22 (18) ◽  
pp. 9670
Author(s):  
Marina Kryuchkova ◽  
Svetlana Batasheva ◽  
Farida Akhatova ◽  
Vasily Babaev ◽  
Daina Buzyurova ◽  
...  
Keyword(s):  
Pharmaceutical Compounds ◽  
Adsorption Properties ◽  
Mass Ratio ◽  
Solution Ph ◽  
Freundlich Model ◽  
Chemical Pollutants ◽  
Natural Clays ◽  
Efficient Adsorbent ◽  
Continuous Accumulation ◽  
Better Than

The problem of purifying domestic and hospital wastewater from pharmaceutical compounds is becoming more and more urgent every year, because of the continuous accumulation of chemical pollutants in the environment and the limited availability of freshwater resources. Clay adsorbents have been repeatedly proposed as adsorbents for treatment purposes, but natural clays are hydrophilic and can be inefficient for catching hydrophobic pharmaceuticals. In this paper, a comparison of adsorption properties of pristine montmorillonite (MMT) and montmorillonite modified with stearyl trimethyl ammonium (hydrophobic MMT-STA) towards carbamazepine, ibuprofen, and paracetamol pharmaceuticals was performed. The efficiency of adsorption was investigated under varying solution pH, temperature, contact time, initial concentration of pharmaceuticals, and adsorbate/adsorbent mass ratio. MMT-STA was better than pristine MMT at removing all the pharmaceuticals studied. The adsorption capacity of hydrophobic montmorillonite to pharmaceuticals decreased in the following order: carbamazepine (97%) > ibuprofen (95%) > paracetamol (63–67%). Adsorption isotherms were best described by Freundlich model. Within the pharmaceutical concentration range of 10–50 µg/mL, the most optimal mass ratio of adsorbates to adsorbents was 1:300, pH 6, and a temperature of 25 °C. Thus, MMT-STA could be used as an efficient adsorbent for deconta×ating water of carbamazepine, ibuprofen, and paracetamol.

scholarly journals Study of sepiolite from Goles (Kosovo, Yugoslavia). II. Acid activation

2002 ◽  
Vol 67 (7) ◽  
pp. 499-506 ◽  
Author(s):  
Marina Radojevic ◽  
Vidojko Jovic ◽  
Dragomir Karaulic ◽  
Dragomir Vitorovic
Keyword(s):  
Specific Surface ◽  
Chemical Treatment ◽  
Acid Treatment ◽  
Nitrogen Adsorption ◽  
Adsorption Properties ◽  
Acid Activation ◽  
Surface Areas ◽  
Bet Method ◽  
Specific Surface Areas ◽  
Enhanced Adsorption

The changes in the pore structure and adsorption properties of sepiolite from Goles resulting from treatment with 4MHCl for various periods of time were investigated. The BET method specific surface areas, pore volumes and f ? plots were determined by nitrogen adsorption. The surface area progressively increased during the 70 hours of acid treatment, when a maximum was attained. The differences in the adsorption properties of the original and the acid treated sepiolite were evaluated by comparison of adsorption isotherms obtained with benzene, n-hexane, methanol and isooctane. The enhanced adsorption of isooctane was of great interest, since the sorption of this compound on natural sepiolites is generally very limited. The results suggest that chemical treatment of sepiolite with 4MHCl for 70 h produces an adsorbent of optimal porosity and other adsorption properties.

Adsorption Properties Graphene-Based Composites on Lead(II) Ions

2021 ◽  
Vol 1036 ◽  
pp. 137-144
Author(s):  
Zhi Bo Sheng ◽  
Chen Kang Wang ◽  
Ling Zheng Wu ◽  
Wen Liang Jin ◽  
Shen You Song Jin
Keyword(s):  
Fourier Transform ◽  
Thermogravimetric Analysis ◽  
Infrared Spectrum ◽  
Adsorption Capacity ◽  
Functional Groups ◽  
Acid Treatment ◽  
Adsorption Process ◽  
Adsorption Properties ◽  
Ft Ir ◽  
Equilibrium Adsorption Capacity

The graphene-based composites was prepared by the oxidation of graphene nano-platelets. The characterization results of thermogravimetric analysis (TGA) and Fourier transform infrared spectrum (FT-IR) indicated that acid treatment can generate abundant functional groups on the surface of graphene. The determined equilibrium adsorption capacity of FGN for lead was 57.765 mg/g, which is higher than that of many currently reports. The adsorption process was completed within 40 min and the adsorption isotherms confirmed to Langmuir classical isotherms models.

Zur Abtrennung von Vanadinfluoriden aus UF6-haltigen Gasströmen / Separation of Vanadium Fluorides from UF6 Containing Gas Streams

1972 ◽  
Vol 27 (7) ◽  
pp. 748-752
Author(s):  
Winfried Kuhrt ◽  
Rolf Kreutz ◽  
Hubert Schindler ◽  
Joachim Massonne
Keyword(s):  
Sodium Fluoride ◽  
Adsorptive Capacity ◽  
Gas Streams ◽  
Surface Active ◽  
Short Time ◽  
Efficient Adsorbent

The preparation of surface active MgF2, CaF2, AlF3 and BiF3 in the shape of pellets is described. The testing of the adsorptive capacity of these pellets as well as of NaF pellets of the commercial qualities at temperatures in the range from 60°C to 400°C showed that sodium fluoride seems to be the most efficient adsorbent for the purification of UF6 containing gas streams from small quantities of VOF3 and VF5 at 250-300°C - a problem occurring at the conversion of uranium. For short-time separations of UFe/VOF3/VF5 or of UF6/VOF3 the use of MgF2 at about 300°C, respectively AlF3 at 100-200°C, may be taken into consideration.

Effects of stereochemistry and alternation on the adsorption properties of surface-active cis- and trans-2-n-alkyl-5-hydroxy-1,3-dioxanes

Langmuir ◽  
1991 ◽  
Vol 7 (8) ◽  
pp. 1765-1769 ◽  
Author(s):  
Klaus. Lunkenheimer ◽  
Bogdan. Burczyk ◽  
Andrzej. Piasecki ◽  
Rolf. Hirte
Keyword(s):  
Adsorption Properties ◽  
Surface Active ◽  
Cis And Trans

Preparation of Ion-Sieve Type (H)[M0.5Mn1.5]O4 (M=Mg, Zn) and their Lithium Adsorption Properties in Seawater

2007 ◽  
Vol 124-126 ◽  
pp. 739-742 ◽  
Author(s):  
Kang Sup Chung ◽  
Mi Ae Kim ◽  
Hwan Lee ◽  
Yong Jae Suh ◽  
Dae Sup Kil ◽  
...  
Keyword(s):  
Solid State ◽  
Hydrochloric Acid ◽  
Acid Treatment ◽  
Selective Adsorption ◽  
Adsorption Properties ◽  
Artificial Seawater ◽  
Hydrochloric Acid Concentration ◽  
Adsorption Efficiency ◽  
Freundlich Equation ◽  
Oxide Spinels

Ion-sieve type manganese oxide spinels for the selective adsorption of lithium(Li) from seawater were prepared and their properties were examined. LiM0.5Mn1.5O4 (M=Mg, Zn) precursors, in which part of manganese(Mn) was substituted with magnesium(Mg) or zinc(Zn), were synthesized through the solid-state reaction. The adsorbents, HM0.5Mn1.5O4 (M=Mg, Zn) were derived from LiM0.5Mn1.5O4 (M=Mg, Zn) by acid treatment. The optimum acid treatment was obtained at hydrochloric acid concentration of 0.5M and 0.3M for LiMg0.5Mn1.5O4 and LiZn0.5Mn1.5O4 precursors, respectively. Both cases required thrice-conducted acid treatments for the best results. The adsorption of Li by HMg0.5Mn1.5O4 and HZn0.5Mn1.5O4 adsorbents followed the Freundlich equation and the maximum adsorption of Li in artificial seawater was 30.3 mg/g and 33.1 mg/g, respectively. The adsorption efficiency of Li by HMg0.5Mn1.5O4 and HZn0.5Mn1.5O4 adsorbents in artificial seawater, in which Li concentration was adjusted to 0.2 mg/L, was as high as 88% and 89%.

Sign in / Sign up

Export Citation Format

Share Document