IN THE NAME OF GOD

Diethylenetriamine-bacterial cellulose (EABC) was synthesized by amination with diethylenetriamine on bacterial cellulose (BC). Its adsorption properties for Cu(II) and Pb(II) were investigated. The parameters affecting the metal ions adsorption, such as contact time, solution pH, and initial metal ions concentration have been investigated. The adsorption kinetics and adsorption isotherms were further studied.

EABC (0.01 g) was added to 10 mL of the different buffered metal ions solutions. The pH was adjusted using 0.1 N HNO3 or 0.1 N NaOH. The mixture was stirred for different times (10–180 min) at room temperature (25 C). The amount of remaining metal ions was determined by an atomic absorption spectrophotometer (ZEEnit 700, German). The amount of metal ions adsorbed on the adsorbent at adsorption equilibrium was calculated according to the following Eq. (1)

4. Conclusion In conclusion, EABC was synthesized and characterized by FT-IR and element analysis. The capacity of EABC in adsorption Cu(II) and Pb(II) was investigated. The experimental data showed that the best adsorption performance of EABC for Cu(II) and Pb(II) ions was obtained in solution at pH 4.5 ± 0.1. The adsorption process reached the adsorption equilibrium at about 2 h. The adsorption kinetics closely followed the pseudo-second-order kinetic model, indicating the importance of chemical adsorption in the process.

We prepared novel Fe 3 O 4 magnetic nanoparticles (MNPs) modified with 3-aminopropyltriethoxysilane (APS) and copolymers of acrylic acid (AA) and crotonic acid (CA). The MNPs were characterized by trans-mission electron microscopy, X-ray diffraction, infra-red spectra and thermogravimetric analysis. We explored the ability of the MNPs for removing heavy metal ions (Cd2+, Zn2+, Pb2+ and Cu2+) from aqueous solution.

We investigated the adsorption capacity of Fe 3 O 4 co-CA at different pH in solution adsorption isotherms, kinetics and thermodynamics were studied to understand the mechanism of the synthesized MNPs adsorbing metal ions the MNPs could efficiently remove the metal ions with high maximum adsorption capacity at pH 5.5 and could be used as a reusable adsorbent with convenient conditions.

Adsorption measurement Adsorption of metal ions from aqueous solution was measured in batch experiments. pH (1.0–8.0), kinetics time (0–90 min), adsorption isotherms (initial concentration 20–450 mg L −1 ) of metal ions (Cd 2+, Zn 2+, Pb 2+ and Cu 2+ ). adding g Fe 3 O 4 to 50 ml of solution of the metal ions at dif-ferent concentrations at 298 K. The equilibrium time was 45 min, when the adsorption behavior reached equilibrium. The adsorbents were separated by powerful magnets.

4. Conclusions We describe the preparation and characterization of MNPs modified with APS and AA-co-CA (Fe 3 O 4 Fe 3 O 4 MNPs are excellent for removal of heavy metal ions such as Cd 2+, Zn 2+, Pb 2+ and Cu 2+ from aqueous solution. Furthermore, the MNPs could efficiently remove the metal ions with high maximum adsorption capacity at pH 5.5 and could be used as a reusable adsorbent with convenient conditions.

Adsorption of Cu(II), Cd(II) and Pb(II) from aqueous single metal solutions by succinylated twice-mercerized sugarcane bagasse functionalized with triethylenetetramine

mass percent gain, concentration of amine groups, FTIR, and elemental analysis. MMSCB 3 and 5 showed mass percent gain of 19.9 and 57.1%,concentration of amine groups of 2.0 and 2.1 mmol/g, and nitrogen content of 5.8 and 4.4%. The capacity of MMSCB 3 and 5 to adsorb Cu 2 ‏, Cd 2 ‏, and Pb 2 ‏ from aqueous single metal ion solutions was evaluated at different contact times, pHs, and initial metal ion concentrations.Adsorption isotherms were well fitted by Langmuir model. Maximum adsorption. capacities of MMSCB 3 and 5 for Cu 2 ‏, Cd 2 ‏, and Pb 2 ‏ were found to be 59.5 and 69.4, 86.2 and 106.4, and mg/g, respectively

The adsorption experiments in this study were carried out in a series of 100 mL Erlenmeyer flasks containing the desired dose of CAS and 50 mL of aqueous Pb(NO3) 2 solution at the desired concentration and initial pH (adjusted with 0.1 N hydrochloric acid or 0.1 N(NaOH) in a shaking bath. After shaking for a certain time, the supernatant was removed and the concentration of Pb (II) was analyzed by atomic adsorption spectrophotometry. All results were performed in triplicate and the data were recorded as a mean (C.V.!5%). The adsorption capacity of the CAS was calculated by the follo wing expression

4. Conclusion The adsorption between Pb (II) ion and crosslinked amphoteric starches (CASs) with quaternary ammonium and carboxymethyl groups is found to be dependent on the pH of the solution, the dose of absorbents, the initial concentration of Pb 2 C ion, as well as the adsorption temperature. The adsorption follows the Langmuir isotherm. The adsorption capacity increases with the increasing DS of the anionic group in the CASs, and reaches to 19.2 and mg/g, respectively, for CAS1 and CAS2 (20–70 mg/L initial concentrations) and mg/g for CAS3 (70–110 mg/L initial concentrations).

The adsorption processes are endothermic, the apparent enthalpies (DHq) are 2.43, and kJ/mol for CAS1, CAS2 and CAS3, respectively, and negative DGq for CAS3 and CAS2 indicates that adsorption happens more readily when the CAS has a higher DS of carboxymethyl groups. Moreover, the adsorption for CAS2 is more dependent on the temperature.

 Alayiding Yushan College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi, Xinjiang , China Received 24 June 2004; revised 16 September 2004; accepted 17 January 2005 Available online 31 March 2005  Universidade Federal de Ouro Preto, Campus Morro do Cruzeiro, Ouro Preto, Minas Gerais, Brazil  State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999#, Rinmin North Road, Shanghai , PR China  Chemistry, School of Chemistry and Chemical Engineering, Shandong University, Jinan , PR China

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