Advanced Materials Research Vols. 550-553

Abstract: Effects of white-rot fungus Trametes sp.lg-9 treatment on properties of chlorine-containing bleaching wastewater were investigated. Trametes sp.lg-9 was cultured in chlorine-containing bleaching wastewater under optimal growth conditions, COD sharply decreased from 10740mg/l to 7811mg/l after 5 days; chroma firstly increased from 6212 degree to 7272 degree at 5 days and then declined to 5303 degree; lignin content firstly increased to 0.33 g/l and then decreased to 0.323 g/l. Separating the crude enzyme solution to treat chlorine-containing bleaching wastewater, demonstrating the suitable temperature of the crude enzyme treatment is 40 °C and the optimum pH value is 5.6. COD, chroma and lignin content of chlorine-containing bleaching wastewater can be significantly reduced by crude enzyme treatment on conditions of low dosage and short time.

Abstract: Investigations and phisibilty studies on using agriculture wastes as a resource for producing energy and materials is regarded insufficient and unsatisfactory. Nonetheless, the utilization of the agriculture solid wastes is suggested a viable solution to reduce pollution and to bring economical benefits. This review study emphasis on the importance of conducting experimental characterization in order to determine which application is suitable for determined waste material. These characterizations could suggest the necessary treatments or methods required to make these materials more efficient as a resource for energy and materials applications. This tailoring may enable researcher to optimize both costs and technical performances of agriculture solid waste as a resource for different application.

Abstract: Phosphate adsorption from aqueous solution using slag was investigated as the function of pH, contact time and adsorbent dosage. The results showed that the optimum value of pH was 2. Both Langmuir isotherm and Freundlich isotherm model were fit to describe the phosphate adsorption, and the maximum adsorption capacity from Langmuir model calculated was 9.09 mg/L. The adsorption process on slag followed pseudo second-order kinetic. Due to the relatively high adsorption capacity, the slag has the potential for application to removal phosphate from wastewater.

Abstract: The adsorption behavior of methylene blue (MB) dye from aqueous solutions onto honeycomb-cinder (HC) and its acid-activated product was investigated in a batch system. The results showed the adsorption capacity was decreased for raw HC samples with the increase of pH value, while it was increased for activated samples. The adsorption data were fit with Langmuir isotherm model for MB adsorption by all samples. The MB adsorption capacity on samples was increased from 2.62 mg/g to 7.81 mg/g and 7.00 mg/g after acid-activated by HCl and H₂SO₄, respectively. The adsorption processes of MB followed pseudo-second-order kinetics with a coefficient of correlation≥0.99. This study demonstrated that acid-activated HC has superior adsorbing ability for MB than raw HC and can be used as alternative adsorbents in dye wastewater treatment.

Abstract: Studies on comparison of principal factors between CAER (China Actual Environmental Risk) and CZER (China Zero Environmental Risk) from Project Angle are seldom found, so we studied the theme above in this thesis. By analysis, we have known that on one hand, there are such aspects in common as projects for resources excavation, and refinement, etc., projects for primary industries, other non-living projects, waste disposal, and general management between CAER and CZER. On the other hand, they are different in such aspects as chemical engineering projects and living projects only for CAER, and energy projects and public construction projects only for CZER. And our related advice is as follows: first, strict management on production of waste from such projects as public construction projects, resources excavation and refinement, natural resources, projects for primary industries, and other non-living projects. Secondly great encouragement to environment-friendly technological innovations in waste disposal, etc..

Abstract: Polypropylene spunbond nonwovens were researched by comparing ultraviolet degradation and weathering-aging. The spunbond nonwoven samples with different content of CaCO₃ were exposed to ultraviolet lights from UVA-340 lambs and natural sunshine. Trends of the decrease of mechanical properties of all samples are similar but the curves in artificial UV degradation are steeper. CaCO₃ can promote the degradation of polymer matrix while weight per unit area has a less impact on the photo-degradation.

Abstract: This article introduces a low-energy preparation method of the insulated sandwich panel from rigid Polyurethane foam wastes through three technological processes of foam cutting, mixture of particles and adhesive, and curing and moulding. It is featured by curing at normal temperature, low energy consumption and simple technologies due to the application of adhesive with the main composition of unsaturated resin that cures at normal temperature. The mechanical property, moisture permeability and thermal insulation of finished products depend on the size and dosage of foam particles and adhesive consumption. Results of tensile test, moisture-permeability test and coefficient of thermal conductivity test on different samples show that the effect of foam particle size can be neglected because it has less influence on the tensile strength, moisture permeability and thermal insulation of insulated sandwich panel; that the tensile strength increases with more foam particles and adhesive used; that the dosage of adhesive is also negligible when its effect on moisture permeability and thermal insulation is evaluated, while the moisture permeability and thermal insulation increase with more foam particles used.

Abstract: Laccase immobilized on polyurethane foam cubes in bioreactors, were used to decolorize three industrial and model dyes at concentrations of 200, 1000 and 2000 ppm. Five sequential cycles were run for each dye and fungus. The activity of laccase, Mn-dependent and independent peroxidases, lignin peroxidase, and aryl-alcohol oxidase were daily monitored during the cycles and the toxicity ofmedia containing 1000 and 2000 ppm of each dye was assessed by the Lemna minor (duckweed) ecotoxicity test. Laccase was able to efficiently decolorize all dyes even at the highest concentration, and the duckweed test showed a significant reduction (p≤ 0.05) of the toxicity after the decolorization treatment. Laccase activities varied greatly and no clear correlation between decolorization and enzyme activity was obselved a high laccase activity during decolorization cycles. Laccase showed better decolorization and detoxication capability.

Abstract: Depolymerization of nylon 6 (PA 6) to obtain caprolactam in the mixture of water and ionic liquid ([Bmim]Cl) was a environmentally benign and high efficient method. There are two reasons for the using of ionic liquid: first is that high H+ concentration in the mixture and the other is that anions of ionic liquid can break the hydrogen bonding of PA 6. The products of depolymerization are analyzed by mass spectrometry and high-performance liquid chromatography and the main is caprolactam. The optimal conditions to obtain caprolactam are determined of reaction temperature 170 °C, IL/H2O (w/w) 13.4%, and reaction time 8 h, and thus the yield of caprolactam 30.7% and degradation of PA 6 94.1%.

Abstract: In order to research the removal effect of potassium ferrate to COD in the different wasterwater, the papermaking wastewater and the tanning wastewater were used as research objects. This paper was focused on evaluating the effectiveness of potassium ferrate preoxidation on COD removal by coagulation in different wastewater of papermaking and tanning. Potassium ferrate is a strong oxidant in the entire pH range: its redox potentials are 2.20 and 0.72 V in acidic and basic media, respectively ferrate (VI) ions will be reduced to Fe (III) ions or ferric hydroxide during the oxidation process, potassium ferrate has also the ability to act as coagulant. The removal efficiency was 78.21% to the papermaking wastewater and 85.51% to the tanning wastewater, respectively, when the dosage concentration of potassium ferrate was 20 mg/L. Altogether, potassium ferrate is a perfect sewage treatment agent to papermaking wastewater and tanning wastewater.