Advanced Materials Research Vols. 535-537

Abstract: A new type of poly(vinyl alcohol)(PVA)/peat/clay composite bead was prepared and shown to be suitable for use as an adsorbent. The mass transport process for the adsorption of metal ions onto the composite beads in an aqueous system was investigated. In the external mass transport process, the rate of ion diffusion decreased and increased with increasing initial metal ion concentrations for Pb+2and Zn+2 ions, respectively. In the intraparticle diffusion process, the diffusion coefficient decreased with increasing initial metal ion concentrations in the range of 1×10-3 to 4×10-3 M, and the diffusion coefficient maintained an almost constant value in the range of 6×10-3 to 22×10-3 M. The rate of ion diffusion within the adsorbent for the Pb+2 ions was faster than that for the Zn+2 ions. The adsorption mechanism was controlled by the intraparticle diffusion process. The maximum amount of adsorbed metal ions at adsorption equilibrium for Pb+2 and Zn+2 ions in this study was 134.57 and 13.28 mg/g composite bead, respectively.

Abstract: The present work investigated the adsorption of thiophene on activated carbons impregnated with PdCl₂ and different kinds of nitrate. The activated carbon was deashed with HCl, oxided with HNO₃ and impregnated with PdCl₂ and one kind of nitrates in acidic media, followed by drying for 12h and roasting at 350°C under N₂ flow. Finally, the model diesel was adsorbed by adsorbent for 12h. They were characterized by N₂ adsorption isotherms, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and gas chromatography. Characterization results provided that the active components of PdCl₂ and Ni(NO₃)₂ were effectively supported on the activated carbon. Organic sulfur compounds are preferentially adsorbed and the desulfurization rate is up to 93.05%.

Abstract: This paper introduces some kinds of UV sterilizers and their characteristics, focusing on system composition, parameter design and characteristics of the new closed UV sterilizer.

Abstract: This article summarizes the research situation of wastewater treatment technology with MBR and modified technology of MBR, especially introduces the efficiency of TiO2-modified PVDF membrane. MBR technology has been widely applied for wastewater treatment and reuse, while its development was always restricted by membrane fouling, but modification can effectively enhance hydrophilic and fouling-resistant ability of the membrane. This paper compares several material modification methods for MBR, and analyses the research situations of PVDF modification with several inorganic nano-particle. The modified MBR with nano-TiO2 has attracted many interests of researchers, which will have a better application and development prospect.

Abstract: Nanosized TiO2 particles were synthesized by sol-gel method using ionic liquid as assistant. The samples were characterized by UV-vis diffuse reflectance spectra, X-ray diffraction (XRD), transmission electron microscopy (TEM). It was shown that the phase detectable was mainly rutile phase with uniform sphericity and the average size was 10nm. Along with the rise of sintering temperature, grain diameter became bigger. The photocatalytic activities of nanosized TiO2 were evaluated by the reduction yield in the presence of CO2 and water. The result showed that TiO2 catalysts has efficient photocatalytic activities, of which made with [OMIM]BF4 displayed the highest photocatalytic active in the experiment.

Abstract: In order to study the purification ability of reed wetland soil to phenol and its influence factors, the dynamic soil column method and static degradation method was conducted, the results indicated that wetland soil without reed-planted had a high purifying efficiency to phenol. Both the residence time of phenol in soil and the range of particle size affect the purifying efficiency of wetland soil to phenol. Reed can affect purifying efficiency of wetland soil to phenol by changing soil infiltration and physicochemical properties of rhizosphere.

Abstract: An intermittent rotation steel spiral automatic cleaning technology has been developed to address the fouling problem of the condenser tubes in small turbines. The intermittent rotation structure reduces steel spiral rotating speed to less than 1/10 of the continuous rotation spiral, which solves the wearing problems between the spiral and the tube. The results of a series of experiments showed that: the proposed technology meets the requirements of cleaning the hard fouling, and the heat transfer enhancement effect is significantly improved. The technology’s simple structure and low cost are suitable for heat exchangers with inside-tube velocity higher than 1 m / s, especially suitable for turbine condenser.

Abstract: In this research, nickel/iron (Ni/Fe) bimetallic nanoparticles were used for the dechlorination of para-nitrochlorobenzene (p-NCB) which could be identified in contaminated soil and wastewater. In the reaction, Ni acted as a collector of hydrogen and the Fe was corroded for producing hydrogen gas. p-NCB was rapidly adsorbed onto the surface of the nanoparticles. Then, p-NCB was degraded to p-CAN and reduced to aniline, or dechlorinated directly to aniline. It was indicated that Ni loading ratio, Ni/Fe mass ratio, and reaction temperature could greatly affect the dechlorination process of p-NCB. Under similar conditions, when 6 g/L of nanoscale Ni/Fe was used, the dechlorination efficiencies reached 25.9 and 100% under 0.5 and 2.0% of Ni/Fe mass ratios, respectively. Thus, a negative linear correlation between the reaction rate and the initial concentration of p-NCB (within a range of 20 to 80 mg/l) could be observed. The reaction activation energy of 94.6 kJ/mol was obtained within the temperature range of 15 to 35 °C.

Abstract: This paper proposes a view to develop low carbon products made from synthetic material of wollastonite by means of four-molding, simple-molding method, joint-mold sleeve tube method and extrusion forming through the analysis on the energy consumption in the manufacturing process of traditional fictile. It conducts comparative study on energy consumption and carbon emission of traditional fictile and energy-conserving products made from synthetic material of wollastonite and verifies the applicable value of low-carbon material, which is the basis for its development.

Abstract: The waste emulsion after recycling,Which was acted as cooling and lubrication in the mechanicalProcessing,can be discharged when it reaches the goal of envirmental protection.The emulsion contains a large number of surfactants and other additives,so this Emulsifying Wastewater is quite stable.However, There is the higher cost in the existing approach of processing.It was reported that The pulse electrolytic process can be used to carry on the treatment the waste emulsion in the text.So the influence on the waste emulsion chemical oxygen demand(COD) elimination rate effect by the factorsof pulse electrolysis were investigated ,such as the electric current size, width pole plate spacing and pH value. The results shown that the shown that: the electrolytic effect of the acidic and neutral media is better than alkaline conditions, electrode spacing can improve the electrolytic effect, and appropriate duty cycle, pulse frequency can play a pulse, not only enhance the electrolytic effect, but also eliminate the passivation effect; it will be effective to take suitable current density.