Pb(II) biosorption on reed biosorbent derived from wetland: effect of pretreatment on functional groups

Reed biomass harvested from wetland constructed for water purification was modified into a biosorbent for Pb(II) removal from aqueous solution. The enhancement of Pb(II) adsorption by reed biosorbent depended not only on the types of reagent used for pretreatment, but also on the pH during the pretreatment process. The mechanisms, as elucidated using relational data obtained from Boehm titration, Fisher esterification and FTIR, involved the conversion of carboxylic groups into carboxylate groups, and proved the role of the carboxylate group, which occupied more than 80% in binding Pb(II). The Langmuir sorption isotherm of Pb(II) by R-NaOH-12 showed Qmax and b values of 0.082 mmol/g and 312.5 g/mmol, suggesting enough adsorption performance to reduce the concentration of Pb(II) to meet the range of WHO guidelines. The salinity of aqueous solution containing NaH2PO4 and NaNO3 promoted the adsorption of Pb(II), while NaCl and Na2SO4 suppressed the adsorption capacity of Pb(II). The adsorption mechanism of reed biosorbent provides valuable insight on the pretreatment effects and the advantages of utilizing this plant as biosorbent for Pb(II) and other heavy metals.

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Dispersion of TiO2 Nanoparticles in Aqueous Solution

Materials Science Forum ◽

10.4028/www.scientific.net/msf.922.8 ◽

2018 ◽

Vol 922 ◽

pp. 8-13

Author(s):

Wen Xiu Liu ◽

Peng Sun ◽

Jun Zhang ◽

Wen Bin Cao

Keyword(s):

Aqueous Solution ◽

Particle Size ◽

Mass Fraction ◽

Adsorption Mechanism ◽

Secondary Particle ◽

Aqueous Dispersion ◽

Ftir Analysis ◽

Carboxylate Groups ◽

The Stability ◽

Potential Test

Stable TiO2aqueous dispersion with an averaged secondary particle size of about 10 nm was achieved by using commercially available dispersant Di-7N. The stability of the dispersion was measured by Zeta-potential test. And the results showed that the optimal mass fraction of Di-7N was 12 wt%. The adsorption mechanism examined by FTIR analysis indicates that the carboxylate groups in Di-7N is absorbed on the surface of nano-TiO2particles and the adsorbed structure is proposed to be bidentate chelating.

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Facile synthesis of a polythiophene/TiO2 particle composite in aqueous medium and its adsorption performance for Pb(ii)

RSC Advances ◽

10.1039/c5ra14614c ◽

2015 ◽

Vol 5 (106) ◽

pp. 86945-86953 ◽

Cited By ~ 26

Author(s):

Jie Chen ◽

Jiangtao Feng ◽

Wei Yan

Keyword(s):

Aqueous Solution ◽

Aqueous Medium ◽

Adsorption Mechanism ◽

Tio2 Particle ◽

Facile Synthesis ◽

Green Method ◽

Particle Composite ◽

Adsorption Performance

A polythiophene/TiO2 particle composite was synthesized by a facile and green method in aqueous medium to adsorb Pb2+ ions from aqueous solution, and both of synthesis and adsorption mechanism were proposed.

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Biochars’ adsorption performance towards moxifloxacin and ofloxacin in aqueous solution: Role of pyrolysis temperature and biomass type

Environmental Technology & Innovation ◽

10.1016/j.eti.2021.101912 ◽

2021 ◽

pp. 101912

Author(s):

Lubna Akhtar ◽

Mahtab Ahmad ◽

Sajid Iqbal ◽

Ahmed A. Abdelhafez ◽

Muhammad Taqi Mehran

Keyword(s):

Aqueous Solution ◽

Pyrolysis Temperature ◽

Adsorption Performance

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Characteristics of Cr (VI) Adsorption in Aqueous Solution by Wheat Straw

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.1262 ◽

2013 ◽

Vol 750-752 ◽

pp. 1262-1266

Author(s):

Li Xiu Peng ◽

Qin Ai Lin

Keyword(s):

Aqueous Solution ◽

Activated Carbon ◽

Wheat Straw ◽

Adsorption Mechanism ◽

Adsorption Process ◽

Adsorption Properties ◽

Effect Factors ◽

Adsorption Time ◽

Initial Concentration ◽

Adsorption Performance

The adsorption process of Cr (VI) in aqueous solution on activated carbon prepared by wheat straw was investigated to study the effect factors on adsorption properties. adsorption mechanism was discussed. The results showed that the adsorption performance was influenced by dosage, initial concentration and adsorption time. Adsorption reached equilibrium after 100 min at temperature 25°C. The highest removal efficiency can reach 94%. The results indicated that activated carbon as adsorbent can effectively deal with waste water containing (VI).

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Simultaneous Removal of Inorganic and Organic Pollutants from Polycontaminated Wastewaters on Modified Hemp-Based Felts

Revista de Chimie ◽

10.37358/rc.21.1.8401 ◽

2021 ◽

Vol 72 (1) ◽

pp. 25-43

Author(s):

Gregorio Crini ◽

Corina Bradu ◽

Cesare Cosentino ◽

Jean-Noel Staelens ◽

Bernard Martel ◽

...

Keyword(s):

Adsorption Mechanism ◽

Adsorption Process ◽

Oxygen Demand ◽

Hemp Fiber ◽

Adsorption Capacities ◽

Carboxylic Groups ◽

Conventional Material ◽

Butanetetracarboxylic Acid ◽

Treatment Step

In this study, an adsorption process using hemp-based materials in felt form was applied to remove between 45 and 53 contaminants present in wastewater from the surface treatment industry. Several materials were compared using batch experiments, including a felt made of 100% hemp fiber (HEMP), the same felt cross-linked with 1,2,3,4-butanetetracarboxylic acid (HEMPBA), a felt coated with a maltodextrin-1,2,3,4-butanetetracarboxylic cross-linked polymer (HEMPM), and a felt coated with hydroxypropyl-a-cyclodextrin-1,2,3,4-butanetetra-carboxylic cross-linked polymer (HEMPCD). Chemical analysis showed that HEMPBA, HEMPM and HEMPCD materials had high adsorption capacities on metals in wastewater, confirming the role of carboxylic groups. Only HEMPCD was able to remove both metals and organics, resulting in the virtual elimination of organics such as chloroform, 1,2-dichlorobenzene, and nonylphenol. This result demonstrated the important role of cyclodextrin molecules in adsorption mechanism. HEMPCD also resulted in an important decrease in residual chemical oxygen demand and total organic carbon of more than 83% and 53%, respectively, while the treatment with HEMP lowered them by 12% and 12%, HEMPBA by 9% and 7%, and HEMPM by 45% and 26%. Chemical abatement and toxicity mitigation have demonstrated that adsorption onto a non-conventional material could be an interesting treatment step for the detoxification of wastewater.

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Preparation and Structure of Zinc Complexes of Cysteine Derivatives

Zeitschrift für Naturforschung B ◽

10.1515/znb-1984-1220 ◽

1984 ◽

Vol 39 (12) ◽

pp. 1732-1737 ◽

Cited By ~ 21

Author(s):

P. Bell ◽

W. S. Sheldrick

Keyword(s):

Structural Analysis ◽

Acid Solutions ◽

Carboxylate Group ◽

Alkaline Ph ◽

Solution Ph ◽

Binding Properties ◽

X Ray ◽

Zwitterionic Form ◽

Carboxylate Groups

Sodium bis(L-cysteinato)zincate(II) hexahydrate (1) and bis(O-ethvl-L -cysteinato)zinc(II) (2) have been prepared from respectively alkaline (pH > 11) and neutral aqueous solutions and their structures determined by X-ray structural analysis. N ,S-coordination of the Zn atoms with the formation of two five-membered chelate rings is observed for both complexes. The deprotonated carboxylate groups in 1 do not coordinate the Zn atom. Dibromo-bis(DL-penicillamine)zinc(II) (3) and dibromo-bis(D-penicillamine)zinc(II) have been isolated from acid solutions with a pH of 2. The penicillamine moieties which are present in the zwitterionic form HS-C(CH3)2-CH(NH3+) - COO- behave as m onodentate ligands with the deprotonated carboxylate group as binding site. The role of solution pH in determining the binding properties of cysteine and penicillamine with zinc(II) is discussed.

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