Studies on the adsorption of sulfo-group-containing aromatics by chitosan-β-cyclodextrin

2012 ◽  
Vol 65 (5) ◽  
pp. 802-807 ◽  
Author(s):  
Wenjian Shi ◽  
Shuwei Chen ◽  
Fei Chang ◽  
Yue Han ◽  
Yuanzhang Zhang
Keyword(s):  
Sulfonic Acid ◽  
Adsorption Process ◽  
Sulfo Group ◽  
Sodium Dodecylbenzene Sulfonate ◽  
Crosslinking Reaction ◽  
Order Model ◽  
Isothermal Adsorption ◽  
Langmuir Adsorption ◽  
Dodecylbenzene Sulfonate ◽  
Naphthalene Sulfonic Acid

Chitosan-β-cyclodextrin (CTS-CD) prepared through a crosslinking reaction between chitosan and β-cyclodextrin was employed to adsorb the three following sulfo-group-containing aromatics: disodium 2-naphthol-3,6-disulfonate (R salt), 2-naphthalene sulfonic acid (NSA), and sodium dodecylbenzene sulfonate (SDBS). At 318 K, the saturated adsorption capacity of CTS-CD for R salt, NSA, and SDBS was 431, 416, and 376 mg/g, respectively. The experimental data fitted the second-order model well and the rate constant of the adsorption increased with the temperature increment. The values of apparent activation energy for R salt, NSA, and SDBS were calculated as 33.2, 34.2, and 16.8 kJ/mol respectively. The isothermal adsorption was found following the Langmuir adsorption equation. The negative values of ΔG and the positive values of ΔH indicated that the adsorption process was spontaneous and exothermic.

scholarly journals Effective removal of Cu2+ ions from polluted water using new bio-adsorbents

2021 ◽  
Vol 16 (2) ◽  
pp. 566-581
Author(s):  
B. Jagadeeswara Reddy ◽  
Sneha Latha Pala ◽  
Wondwosen Kebede Biftu ◽  
M. Suneetha ◽  
Kunta Ravindhranath
Keyword(s):  
Functional Groups ◽  
Adsorption Process ◽  
Polluted Water ◽  
Order Model ◽  
Langmuir Adsorption ◽  
Effective Removal ◽  
High Sorption ◽  
Pseudo Second Order ◽  
Surface Complex Formation ◽  
Polluted Lake

Abstract Sorbents derived from stem powders of Feronia limonia (FLSP), Amorphophallus paeoniifolius (APSP) and Pumpkin (Cucurbitapepo) (PSP) plants are investigated for the removal of Cu2+ ions from polluted water by adopting batch methods of extraction. Extraction conditions are optimized for the effective removal of Cu2+ ions. High sorption capacities are observed: 175.5 mg/g for FLSP; 140.4 mg/g for APSP; 130.0 mg/g for PSP. Effective pH ranges are: 5 to 10 for FLSP; 6 to 10 for APSP and 7 to 10 for PSP. The three spent adsorbents can be regenerated and used. Thermodynamic parameters indicate that the adsorption process is spontaneous, endothermic and have positive change in entropy values. As ΔH values are more than 25.0 kJ/mole, the adsorption may be due to surface complex formation between Cu2+ ions and functional groups of the adsorbents viz., -OH, -COOH etc. in the effective pH ranges. The good adsorption behaviour of FLSP even in acidic pHs may be due to the ion-exchange of Cu2+ ions for H+ ions of the functional groups of the adsorbent. The Langmuir adsorption isotherm and pseudo second-order model describe well the adsorption process. The sorbents are effectively applied to treat effluents from Cu-based industries and polluted lake water.

scholarly journals Study on the adsorption of Rhodamine B on MoS2/RGO composite

2020 ◽  
Vol 9 (4) ◽  
pp. 57-63
Author(s):  
Trang Phan Thi Thuy ◽  
Tam Truong Thanh ◽  
Vien Vo ◽  
Lien Nguyen Hong
Keyword(s):  
Room Temperature ◽  
Adsorption Process ◽  
Organic Dyes ◽  
Maximum Adsorption Capacity ◽  
Order Model ◽  
Langmuir Adsorption ◽  
Reduced Graphene ◽  
Effects Of Ph ◽  
Pseudo Second Order ◽  
Oxide Composite Material

In this study, MoS2/RGO (reduced graphene oxide) composite material was synthesized and tested for adsorption of RhB in water. The adsorption studies were carried out at room temperature and the effects of pH, amount of adsorbents, concentration of adsorbate and time of adsorption on the adsorption were measured. In addition, the dynamics of the adsorption process was also investigated. The results showed that the MoS2/RGO composite displayed toward RhB with maximum adsorption capacity reaching q = 57.79 mg/g at pH = 3.54 and the adsorption process follows the Langmuir adsorption isotherm with the pseudo-second-order model. Findings from this research indicated that the graphene based semiconductor MoS2/RGO composite could be considered a promising adsorbent for removal of organic dyes from waste waters.

scholarly journals USE OF SURFACTANTS ADDED TO REFRACTORY SLURRY IN PRECISION FOUNDRY AND INVESTMENT CASTINGS WITH ALUMINUM

1994 ◽  
Vol 2 (2) ◽  
pp. 41-54
Author(s):  
Arno Mllller ◽  
Jorge Luiz S. Barcelos ◽  
Lavinel G. IONESCU
Keyword(s):  
Sulfonic Acid ◽  
Casting Process ◽  
Visual Observation ◽  
Sodium Dodecylbenzene Sulfonate ◽  
Monolayer Film ◽  
Food Industries ◽  
Dodecylbenzene Sulfonate ◽  
Ceramic Slurry ◽  
Dioctyl Sodium Sulfosuccinate ◽  
Metal Castings

The investment casting process, involving wax models invested with clays to give ceramic molds from which metal castings are made, is characterized by the obtainment of parts of high metallurgic quality, especially as far as dimensional aspects the complexity of design and surface finishings are concerned. The high-precision parts have a wide application in the electronic, aeronautical, biomedical, textile, and food industries. Twenty-one different surfactants, added to refractive zirconite slurry, were tested for their efficiency in obtaining wetting and adherence to the surface of the wax and good quality finished aluminum parts. Only five surfactants, including sodium dodecylbenzene sulfonate, sulfonic acid, dioctyl sodium sulfosuccinate, and ethoxylated long-chain alcohols, gave satisfactory results. Analysis of the specimens manufactured from 98% aluminum, poured at 710 °C, by visual observation, rugosity, optical photography, and electron microscopy showed that they were of high quality. The present paper describes the results obtained with sulfonic acid C 8-l6 and sodium dodecylbenzene sulfonate and explains the effect of the surfactants by the formation of a monolayer film or hemi-micelles between the wax and the ceramic slurry.

Study on the Formaldehyde Adsorption Kinetics of Dry Waters

2014 ◽  
Vol 809-810 ◽  
pp. 907-911
Author(s):  
Jun Long Wang ◽  
Jie Hou ◽  
Ting Jiang ◽  
Yong Jun He ◽  
Yao Dong Liang
Keyword(s):  
Adsorption Kinetics ◽  
High Speed ◽  
Adsorption Process ◽  
Average Diameter ◽  
Adsorption Rate ◽  
Absorption Kinetics ◽  
Order Model ◽  
Pseudo Second Order ◽  
Kinetics Of ◽  
Formaldehyde Adsorption

Dry waters with an average diameter of 82 μm were prepared by a high speed mixed route. The formaldehyde absorption kinetics of dry waters was investigated by simulating indoor formaldehyde pollution in glass chamber. The results showed that pseudo-second order model could be used to simulate the adsorption process; the adsorption rate was highest in the initial 60 minutes; when the adsorption lasted for 180 minutes, the adsorption reached equilibrium.

Effects of tall fescue biochar on the adsorption behavior of desethyl-atrazine in different types of soil

BioResources ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. 3575-3595
Author(s):  
Wanting Li ◽  
Ruifeng Shan ◽  
Yuna Fan ◽  
Xiaoyin Sun
Keyword(s):  
Tall Fescue ◽  
Adsorption Process ◽  
Exothermic Reaction ◽  
Equilibrium Concentration ◽  
Black Soil ◽  
Adsorption Behavior ◽  
Order Kinetic ◽  
Isothermal Adsorption ◽  
Order Kinetic Model ◽  
Pseudo Second Order

Desethyl-atrazine (DEA) is a metabolite of atrazine that exerts a considerable influence on the environment. In this study, tall fescue biochar was prepared by pyrolysis at 500 °C, and batch experiments were conducted to explore its effect on the adsorption behavior of DEA in red soil, brown soil, and black soil. The addition of biochar increased the equilibrium amount of DEA adsorption for the three soil types. A pseudo-second-order kinetic model most closely fit the DEA adsorption kinetics of the three soils with and without biochar, with a determination coefficient (R2) of 0.962 to 0.999. The isothermal DEA adsorption process of soils with and without biochar was optimally described by the Freundlich and Langmuir isothermal adsorption models with R2 values of 0.98 and above. The DEA adsorption process in the pristine soil involved an exothermic reaction, which became an endothermic reaction after the addition of biochar. Partitioning was dominant throughout the entire DEA adsorption process of the three pristine soils. Conversely, in soils with biochar, surface adsorption represented a greater contribution toward DEA adsorption under conditions of low equilibrium concentration. The overall results revealed that the tall fescue biochar was an effective adsorbent for DEA polluted soil.

scholarly journals ADSORPTION AND KINETIC STUDIES OF A NATURAL DYE FROM CURCUMA LONGA L., ONTO BAMBOO YARN

2017 ◽  
Vol 2 (1) ◽  
pp. 13-26
Author(s):  
Tengku Khamanur Azma Tg. Mohd Zamri ◽  
Mimi Sakinah Abd Munaim ◽  
Zularisam Ab Wahid
Keyword(s):  
Adsorption Process ◽  
Regression Coefficient ◽  
Curcuma Longa ◽  
Freundlich Isotherm ◽  
Kinetic Studies ◽  
Natural Dye ◽  
Isotherm Models ◽  
Order Model ◽  
Dyeing Process ◽  
Pseudo Second Order

Natural dye extracted from the rhizome of Curcuma longa L. were applied to bamboo yarns using exhaustion dyeing process. This study investigates the dyeing behaviour of Curcumin; the major color component isolated from rhizomes of Curcuma longa L.on bamboo yarn. Langmuir, Freundlich, Tempkin and Dubinin-Radushkevich isotherm models were used to test the adsorption process of curcumin on bamboo yarn. Comparison of regression coefficient value indicated that the Freundlich isotherm most fitted to the adsorption of curcumin onto bamboo yarn. Furthermore, the kinetics study on this research fitted the pseudo-second order model which indicates that the basis of interaction was chemical adsorption.

scholarly journals Equilibrium and Kinetic Study of Lead and Copper Ion Adsorption on Chitosan-Grafted-Polyacrylic Acid Synthesized by Surface Initiated Atomic Transfer Polymerization

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2218 ◽  
Author(s):  
Carlos Grande-Tovar ◽  
William Vallejo ◽  
Fabio Zuluaga
Keyword(s):  
Adsorption Capacity ◽  
Polyacrylic Acid ◽  
Adsorption Process ◽  
Kinetic Constant ◽  
Copper Ion ◽  
Toxic Metal ◽  
Maximum Adsorption Capacity ◽  
Order Model ◽  
Equilibrium Studies ◽  
Pseudo Second Order

In this work, we synthesized chitosan grafted-polyacrylic acid (CS-g-PA) through surface-initiated atom transfer radical polymerization (SI-ATRP). We also studied the adsorption process of copper and lead ions onto the CS-g-PA surface. Adsorption equilibrium studies indicated that pH 4.0 was the best pH for the adsorption process and the maximum adsorption capacity over CS-g-PA for Pb2+ ions was 98 mg·g−1 and for Cu2+ it was 164 mg·g−1, while for chitosan alone (CS), the Pb2+ adsorption capacity was only 14.8 mg·g−1 and for Cu2+ it was 140 mg·g−1. Furthermore, the adsorption studies indicated that Langmuir model describes all the experimental data and besides, pseudo-second-order model was suitable to describe kinetic results for the adsorption process, demonstrating a larger kinetic constant of the process was larger for Pb2+ than Cu2+. Compared to other adsorbents reported, CS-g-PA had comparable or even superior adsorbent capacity and besides, all these results suggest that the new CS-g-PA polymers had potential as an adsorbent for hazardous and toxic metal ions produced by different industries.

scholarly journals Inhibition of Pipeline Steel Corrosion in 0.5 M H2SO4 Using Cotyledon of Chrysophyllum Albidum

2020 ◽  
Vol 24 (4) ◽  
pp. 691-697
Author(s):  
E.P. Othaki ◽  
N.C. Ngobiri
Keyword(s):  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Adsorption Process ◽  
Pipeline Steel ◽  
Steel Corrosion ◽  
Langmuir Adsorption ◽  
Extract Concentration ◽  
Ir Studies ◽  
Ft Ir ◽  
As Adsorption

The corrosion inhibition characteristics of Chrysophyllum albidum cotyledon extract was studied as a green and sustainable corrosion inhibitors for pipeline steel in acidic environment attemperatures, 303,313 and 323K using gravimetric technique.The results obtained showed that the inhibition efficiency increased with increase in extract concentration but decrease with increase in temperature. The extract attained an inhibition efficiency of 94 % with 5 g/L at 303 K and 52.2 % with 1 g/L at 333K. Also increase in concentration of the extract lead to increase in activation energydepicting an exothermic process.Fourier transform infrared spectroscopy (FT-IR) studies showed the mode of inhibition as adsorption of phytochemicals from the extract on pipeline steel surface. Langmuir adsorption isotherm best fitted into the adsorption process which is spontaneous and physical. Keywords: Chrysophyllum albidum, Pipeline steel, Inhibition, Adsorption.

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