Papers by Author: Min Cong Zhu

Abstract: In order to generate powerful radicals as oxidizing species for the complete oxidation of NO, homogeneous activation of peroxymonosulfate (Oxone: PMS) by the Mn₃O₄/GO catalysts was explored. The catalytic oxidation of NO from waste gas was investigated using advanced oxidation process based on sulfate radicals that produced. The manganese oxide immobilized on graphene oxide (GO) can activate PMS for the oxidation of NO in water. We not only took advantage of the high oxidation–reduction potential of produced sulfite radicals but also an opportunity to oxidize NO on less complex compounds with low dosages. The Mn₃O₄/GO catalysis system was characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that Mn₃O₄ was well-distributed on GO. The Mn₃O₄/GO catalyst system exhibited high efficiency for NO oxidation when the Mn₃O₄/GO catalyst has an optimum Mn₃O₄ loading. In addition, the best catalytic oxidation can be achieved within 30 min with pH 4 and 6 mM PMS at 25 °C. Therefore, the results indicate promising potential for a system utilizing Mn₃O₄/PMS to oxidize NO for offgas treatment.

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: 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.