Cloreto de n-(2-hidroxil) propil-3-trimetil amônio quitosana como adsorvente de corantes reativos em solução aquosa

Fávere, Valfredo T.; Riella, Humberto Gracher; Rosa, Sirlei da

doi:10.1590/s0100-40422010000700010

Cited by 25 publications

(18 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Similar to Freundlich´s model, the parameters of Dubinin-Radushkevich´s mathematical model (D-R) may also be employed to explain the mechanisms of the adsorption process of the metals under analysis. The adsorption process of Cu 2+ by the three biosorbents has chemical characteristics since E rates are higher than 8.0 kJ [52] when average sorption energy (E) mol -1 is taken into account. The latter corresponds to the free energy involved in the transference of 1 mol of the solution´s solute to the adsorbent´s surface and thus indicates whether adsorption has physical or chemical features [53].…”

Section: +mentioning

confidence: 99%

Adsorption of Cu (II) and Zn (II) from Water by Jatropha curcas L. as Biosorbent

et al. 2016

View full text Add to dashboard Cite

Abstract:The objective of this work was to evaluate the removal of Cu 2+ and Zn 2+ in water by means of the adsorption process using three biosorbents derived from jatropha biomass (bark, endosperm and endosperm + seed coat). The experiments were performed in batch and evaluated the effect of solution pH, adsorbent mass, contact time, different initial concentrations of the metals Cu 2+ and Zn 2+, and the temperature of the solution during the adsorptive process. By kinetics, the adsorption isotherms and thermodynamics the mechanisms that control the adsorptive process were evaluated. The optimal conditions for the realization of the adsorptive process for both metals were: solution pH of 5.0 and 8 g L -1 of adsorbent mass per volume of solution, with a contact time between adsorbent and adsorbate of 60 min. According to the Langmuir model, the maximum adsorption capacities for the bark, endosperm and endosperm + seed coat of Jatropha were, respectively, for Cu 2+ 11.541, 20.475 and 22.910

show abstract

Section: +mentioning

confidence: 99%

Adsorption of Cu (II) and Zn (II) from Water by Jatropha curcas L. as Biosorbent

et al. 2016

View full text Add to dashboard Cite

show abstract

“…35 The mathematical model of Dubinin-Radushkevich is based on the heterogeneity of the adsorbent surface. This model is widely used for differentiation of a process of physical or chemical nature 5 and is represented by Equation 11:…”

Section: Adsorption Isothermsmentioning

confidence: 99%

Biosorption and removal of chromium from water by using moringa seed cake (Moringa oleifera Lam.)

et al. 2013

View full text Add to dashboard Cite

Recebido em 14/11/12; aceito em 13/5/13; publicado na web em 17/7/13 This study evaluated the adsorption capacity of chromium from contaminated aqueous solutions by using Moringa oleifera Lam. seeds. Parameters such as solution pH, adsorbent mass, contact time between solution and adsorbent, isotherms, thermodynamic, kinetics, and desorption were evaluated. The maximum adsorption capacity (Q m ) calculated to be 3.191 mg g −1 for the biosorbent. Activated carbon was used for comparison purposes in addition to the biosorbent. The best fit was obtained by the Langmuir model for both adsorbents. The average desorption value indicated that both the biosorbent and activated carbon have a strong interaction with the metal. The results showed that the biosorbent has advantages owing to its low cost and efficiency in Cr 3+ removal from contaminated waters.

show abstract

“…The Freundlich isotherm describes equilibrium on heterogeneous surfaces and assumes a monolayer adsorption capacity [40]. This explanation could justify the good fits of the materials used in this model because these adsorbents came from natural sources and were expected to exhibit the behavior of heterogeneous surfaces.…”

Section: Resultsmentioning

confidence: 99%

Preliminary assessment of the performance of oyster shells and chitin materials as adsorbents in the removal of saxitoxin in aqueous solutions

Melegari¹,

Matias

2012

Chemistry Central Journal

View full text Add to dashboard Cite

BackgroundThis study evaluated the adsorption capacity of the natural materials chitin and oyster shell powder (OSP) in the removal of saxitoxin (STX) from water. Simplified reactors of adsorption were prepared containing 200 mg of adsorbents and known concentrations of STX in solutions with pH 5.0 or 7.0, and these solutions were incubated at 25°C with an orbital shaker at 200 RPM. The adsorption isotherms were evaluated within 48 hours, with the results indicating a decrease in STX concentrations in different solutions (2–16 μg/L). The kinetics of adsorption was evaluated at different contact times (0–4320 min) with a decrease in STX concentrations (initial concentration of 10 μg/L). The sampling fractions were filtered through a membrane (0.20 μm) and analyzed with high performance liquid chromatography to quantify the STX concentration remaining in solution.ResultsChitin and OSP were found to be efficient adsorbents with a high capacity to remove STX from aqueous solutions within the concentration limits evaluated (> 50% over 18 h). The rate of STX removal for both adsorbents decreased with contact time, which was likely due to the saturation of the adsorbing sites and suggested that the adsorption occurred through ion exchange mechanisms. Our results also indicated that the adsorption equilibrium was influenced by pH and was not favored under acidic conditions.ConclusionsThe results of this study demonstrate the possibility of using these two materials in the treatment of drinking water contaminated with STX. The characteristics of chitin and OSP were consistent with the classical adsorption models of linear and Freundlich isotherms. Kinetic and thermodynamic evaluations revealed that the adsorption process was spontaneous (ΔGads < 0) and favorable and followed pseudo-second-order kinetics.

show abstract

Cloreto de n-(2-hidroxil) propil-3-trimetil amônio quitosana como adsorvente de corantes reativos em solução aquosa

Cited by 25 publications

References 28 publications

Adsorption of Cu (II) and Zn (II) from Water by Jatropha curcas L. as Biosorbent

Adsorption of Cu (II) and Zn (II) from Water by Jatropha curcas L. as Biosorbent

Biosorption and removal of chromium from water by using moringa seed cake (Moringa oleifera Lam.)

Preliminary assessment of the performance of oyster shells and chitin materials as adsorbents in the removal of saxitoxin in aqueous solutions

Contact Info

Product

Resources

About