Papers by Author: Ying Chen Zhang

Abstract: Expanded graphite (EG) was prepared by microwave irradiation at 1000 w for 60 s. It is a novel adsorbent for Pb (Ⅱ) adsorption. This paper aims to investigate the effect of the adsorption of EG. The adsorption behavior of Pb (Ⅱ) from aqueous solution onto EG was investigated with variety of parameters such as pH, adsorbents dosage, initial Pb (Ⅱ) concentration, contact time and temperature. On conditions that the pH=6.04,the dosage of adsorbent was 0.075g, the concentration of Pb(Ⅱ) was 100mg/L and the temperature was 15°C, the maximum removal rate could reach at 86.55% .The results showed that the EG was an efficient and novel adsorbent for the removal of lead from aqueous solution. The microstructures of the resultant expanded graphite were observed by scanning electron micrographs.

Abstract: A simple method was developed for the preparation of zinc oxide (ZnO) nanofibers grafted on the expanded graphite(EG) under routine conditions. The synthesized materials were characterized by infrared spectroscopy (IR), scanning electron microscopy (SEM) and X-ray diffractometer (XRD). The results show that the ZnO nanofibers, with a diameter of 50-150 nm, were randomly deposited on the expanded graphite.

Abstract: The expanded graphite coated with different portions of Fe₃O₄ nanoparticles (EG/ Fe₃O₄) were synthesized by a simple hydrothermal reaction and the composite was characterized by scanning electron micrograph (SEM), X-ray diffraction (XRD) and infrared spectroscopy (IR). The catalytic performance of the composite was studied through the degradation of methylene blue. The results indicated that a complete and uniform Fe₃O₄ nanoparticles coating on expanded graphite could be obtained under routine pressure and temperature and the optimum content of Fe₃O₄ in the composite was 6wt% in the experiment of catalytic degradation of methylene blue.

Abstract: Expanded graphite (EG) was prepared by microwave irradiation at 1000 w for 60 s. It is a novel adsorbent for Sn (Ⅱ) adsorption. This paper aims to investigate the effect of the adsorption of EG. The adsorption behavior of Sn (Ⅱ) from aqueous solution onto EG was investigated with variety of parameters such as pH, adsorbents dosage, initial Sn (Ⅱ) concentration, contact time and temperature. On conditions that the pH was 2.5, the dosage of adsorbent was 0.02 g, the concentration of Sn (Ⅱ) was 200 mg/L and the temperature was 15°C, the maximum removal rate can reach to 98.32%, and the adsorption quantity can reach to 245.7985 mg•g-1. The results showed that the EG was an efficient and novel adsorbent for the removal of stannum from aqueous solution.

Abstract: A new material on adsorption of Pb(Ⅱ) was introduced in this paper. EG was modified by soaking in KOH. MEG (modified expanded graphite) was characterized by SEM, XRD and FTIR. The removal rate of Pb(Ⅱ) rose to 92.23% from 59.14% on MEG . And the adsorption quantity came up to 46.3869mg/g from 31.9662mg/g. All above shows that MEG has better adsorption performance.

Abstract: In the present work, expanded graphite (EG) was prepared by microwave irradiation. Then, the expanded graphite/polyaniline (EG/PANi) composite was synthesized in the typical method. The samples of EG and EG/PANi were characterized by SEM and IR analysis techniques. Adsorption property of EG/PANi composite for removing the dye, reactive brilliant red K-2BP, from aqueous solution was investigated. The effects of initial dye concentration and contact time, pH, sorbent dosage on the adsorption process were studied. Experimental data were modelled by Langmuir and Freundlich isotherms. Langmuir isotherm model fitted well the equilibrium data for EG/PANi composite comparing to the Freundlich isotherm model. The uptake capacity of EG/PANi for K-2BP was found to be 1.03047 mg/g. The results indicated that EG/PANi composite is not an ideal sorbent used for reactive dye removal.

Abstract: The expanded graphite (EG) was prepared after microwave irradiation treatment of the expandable graphite in a domestic microwave oven at 1000 W for 60 s. The adsorption of methyl orange (MO) from aqueous solution onto EG was investigated at initial concentrations and contact time, different pH values, adsorbent dosage, temperatures for the removal of dye. The results confirmed that the adsorption isotherm data fitted to Langmuir isotherm with monolayer adsorption capacity of 13.37 mg/g. The results suggested that the EG would be an excellent adsorbent for the removal of MO by adsorption process.

Abstract: This paper deals with the synthesis and characterization of poly(ethylene glycol)-grafted expanded graphite (PEG-grafted EG) as a novel composite material. The PEG-grafted EG composite was prepared by grafting PEG in the EG layers using isophorone diisocyanate (IPDI) as coupling agent. The EG was prepared after microwave irradiation treatment from the expandable graphite, the obtained EG modified by an excess amount of IPDI. Modified expanded graphite (MEG) mixed in anhydrous N,N-dimethylformamide (DMF) and grafted PEG at low temperature atmosphere. The samples of EG and PEG-grafted EG composite was characterized by using scanning electron microscopy (SEM), infrared spectroscopy (IR) and thermogravimetric (TG) analysis technique.

Abstract: A composite photo-catalyst of nano-TiO2 (TIO) grafted in the pores of expanded graphite (EG) was prepared by a process that included microwave irradiation method and hydrolysis method directly. Fourier transformation infrared spectroscope (FT-IR), Scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDS) were used to characterize the structure and the chemical structure of the photo-catalyst. The results indicate that expanded graphite had a unique net-like pores structure and nano TiO2 was loaded on EG to form EG/ TiO2 (EGTIO) composite photo-catalyst.

Abstract: A composite photocatalyst of needle nano-ZnO grafted in the pores of expanded graphite (EG) was prepared by a process of hydrolysis method directly, in which the expanded graphite was prepared by microwave irradiation. Scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and Fourier transformation infrared spectroscope (FT-IR) were used to characterize the structure and the chemical structure of the photo-catalyst. The results indicate that expanded graphite had a unique net-like pores structure and needle nano-ZnO was loaded on EG to form EG/ZnO composite photo-catalyst.