Advanced Materials Research Vols. 518-523

Abstract: γ-Al₂O₃ was used as carrier and Fe/γ-Al₂O₃ catalyst were prepared by wet impregnation and ultrasonic infiltration method and characterized by specific surface area and pore distribution (BET), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and x-ray diffraction (XRD). Specific surface area of Fe/γ-Al₂O₃ catalyst was 224.93m²/g from BET analysis. Active component of catalyst was attached on the surface of carrier from the characterization of SEM and EDS. The prepared catalyst was used for the catalytic degradation of formaldehyde wastewater. The results indicated that the efficiency of H₂O₂/Fe/γ-Al₂O₃ catalytic oxidation was better than Fe/γ-Al₂O₃ catalytic oxidation and H₂O₂chemical oxidation.

Abstract: The objective of this study is preparing a novel environmental friendly light weight magnetic sorbent consisting of bacteria and cobalt by chemical process to further cleaning crude oil spills in sea. The observations by ESEM indicated that a thin granular layer covered on the surface of model microorganism of Staphylococcus epidermildis which provided host for absorbing cobalt ions and depositing cobalt particulates. The results showed that composite present flower-like microspheres with large-scale yields. The high temperature treatment of amorphous bacteria composited cobalt microspheres showed that it well crystallized corresponding to Co3O4 at 800 °C. The microorganism composited magnetic sorbent opens an important alternation absorbent for timely oil spill cleanup.

Abstract: A constant direct current density of 0.5 mA/cm² was applied in a laboratory experiment for studing the feasibility of electrokinetic treatment on the removal of Cd from red soils. The result shows that the removal efficiency of Cd was remarkably pH-dependent. The initial Cd concentration was1490 mg/kg and over 79% of Cd was removed from the red soils after 96 hours’ treatment. The energy expenditure was about 77.6 kW.h/m³ and the cost was 42.6 RMB Yuan/m³, which suggest that electrokinetic soil processing is a promising technology for remedying cd-contaminated red soils.

Abstract: Direct discharge of livestock wastewater and domestic sewage in rural areas, not only cause serious pollution to the environment, but also waste resources, this article introduces the main technology of sewage, wastewater treatment, main treatment processes and reuse method, pointing out the resource recycling of wastewater is an important way to ease the aquatic environment serious deterioration.

Abstract: Enrichment capacity and transfer capability of R. acetosa were studied in situ at the different growth stages, and the soil was polluted by the two levels (T₁: Cd 0.70 mg/kg+Cu 114.37 mg/kg+Pb 138.94 mg/kg; T₂: Cd 1.34 mg/kg+Cu 164.90 mg/kg+Pb 176.19 mg/kg) of combined heavy metals. The results showed that the content of Cd, Cu and Pb in roots increased first, then decreased and increased again as R. acetosa growing in each test area. And the content of Cd, Cu and Pb in shoots showed the same trend as roots. The enrichment capacity of R. acetosa to Cu and Pb was improved as the level of heavy metal pollution increased at the different growth stages, while the Cd was in inverse proportion to the concentration. But its enrichment capacity and transfer capability of Cd to be significantly higher than Cu and Pb. R. acetosa application on the bioremediation of soil polluted by combined heavy metals of Cd, Cu and Pb showed great potential.

Abstract: Although the concentration of highway runoff’s contaminants is low, highway runoff still have potential risks to the surrounding environment due to the accumulation effect. Infiltration system is a common method to control highway runoff pollution; therefore, this paper used Zn²⁺, P and petroleum that are typical dissolved pollutant in runoff as the target pollutants to investigate the effect of different filter materials removing highway runoff pollutants. The result shows that river sand’s removal effect is better than zeolite, in the experimental period, the efficiency of the river sand column removing Zn²⁺ was higher than 95%, and removal efficiency for Zn²⁺ of the zeolite column was higher than 90% at the first three days’ supply of Zn²⁺ solution, then gradually decreased. Adding a small amount of gravel was appropriate to help increase their infiltrate rate under high removal efficiency, the infiltrate rate of packed column reached 4 mm • min^-1 when its mass ratio of river sand and gravel is 2:1, and its effect on the removal of pollutants was also evident. The way of water flowing through the column from its bottom to upper can help alleviate the clog of packed column.

Abstract: Based on the statistical data of Changsha-Zhuzhou-Xiangtan (CZT) urban agglomeration from the year 2005 to 2010, the environmental learning curves of sulfur dioxide emission per 10 thousand Yuan (RMB) production value and per capita gross domestic product (GDP) were established, and sulfur dioxide emission reduction potential of these cities was analyzed. The results show that the sulfur dioxide emission per 10 thousand Yuan production value declined exponentially with the increase of per capital GDP. From the perspective of time, the sulfur dioxide emission per 10 thousand Yuan production value is declining year by year along with economical development and level of technology improvement; from the perspective of space, the city with the largest potential of sulfur dioxide emission reduction is Zhuzhou, followed by Xiangtan, and then Changsha.

Abstract: _{Subscript text}In this text, Ti/TiO₂-SnO₂ composite electrodes were prepared by Sol-Gel method. Rare earth-doped method can improve the catalytic performance of the composite electrodes. Based on the degradation of oil-field wastewater, e of the electrode surface and the element composition of surface layers were analyzed by SEM, EDX and XRD. When the current density was 30mA/cm², electrode submersed area was 2cm², pH was 3~5, temperature was 30°C and the electrolysis time was 60min, the best treatment process was obtained. The average removal rate of oil content and CODcr were 92.8% and 89.2%, respectively. Under the best treatment process the contaminant was degradated to other intermediate substances during degradation, finally mineralized to CO₂ and H2O.

Abstract: The polyvinyl alcohol (PVA) wastewater was pretreated by the process of flocculation-Fenton oxidation. Raw wastewater was treated by the different flocculants first. The results showed that when the flocculant FeSO₄ was used, its effect was better than Fe₂(SO₄)₃ and PAC, the dosage of it was 10g/L, under which COD removal efficiency reached 61.72%. The effects of FeSO4 and H₂O₂ addition and pH on treatment effect were studied in the follow-up Fenton oxidation. The results showed that when the addition of FeSO₄ was 20g/L, the dosage of H₂O₂ was 250mL/L, pH was 4, the removal efficiency of COD reached over 90%. The experiments of fractionated adding the reagents showed that the removal rate of COD was significantly higher in the situation of fractionated adding FeSO₄ required in the flocculation and Fenton oxidation process than one-time added. The removal rate of COD changed little when the H₂O₂ fractionated addition in the process of Fenton oxidation.

Abstract: China’s oil resource consumption is in the forefront of the world, but the per capita storage capacity of the oil resources is inadequate. With the improvement of the strategic position of the oil resources and the progress in exploitation technology, China has implemented the “go out” strategy, and is continuously seeking cooperative exploitation overseas. However, considered the great cultural difference between China and foreign countries, the oversea cooperation has many obstacles. The recent oil spilling incident of Penglai 19-3 was a minor accident, but finally it has become a major one. So the cultural gap between China and foreign countries really exists, and even more, it is very important. This paper is based on the Penglai19-3 accident and is trying to discuss how to reduce the cultural gap between two countries, so that the oversea cooperation can develop successfully.