CO还原脱硝反应锌铜双金属有机骨架催化剂的制备

采用离子交换法制备锌铜双金属有机骨架(Zna/HKUST-1,a=1/24,1/12,1/6,1/3,a为Zn与Cu的摩尔比),用于催化CO还原脱硝反应。采用XRD,SEM,FTIR,H2-TPR,BET等方法对Zna/HKUST-1进行了表征。表征结果表明:Zna/HKUST-1中有明显的Zn—O键和铜基金属有机骨架(HKUST-1)的结构,证明Zn成功进入了HKUST-1中;但随a的不同,Zna/HKUST-1的形貌、大小及比表面积出现了差异。实验结果表明,Zna/HKUST-1(a=1/24)对CO还原脱硝反应的催化活性最高,可在230℃达到NO转化率100%。     

Biodegradable Complex Polymers from Casein and Potato Starch

Potato starch was blended with defatted milk in proportions providing a 4:1, 3:1, 2:1, 1:1, 1,:2, 1:3, and 1:4 starch/casein ratio. Precipitation was achieved by addition of either hydrochloric acid or leaven. Composition of precipitated products was determined based on elemental analysis for nitrogen. Generally, differences between attempted and achieved casein-to-starch proportions did not exceed 10%. Products coprecipitated with hydrochloric acid were slightly richer in casein than products obtained with leaven. Aqueous solubility, water binding capacity, IR spectra, and thermal analysis (thermogravimetry, TG, and differential thermogravimetry, DTG) were recorded for the precipitates. Analyses revealed that the precipitates were not simple physical mixtures of the components. Partial insolubility in 7 M aqueous urea showed that casein and potato starch are chemically bound. Comparison of the spectra and thermograms suggested that complexes of the 1:1 composition were formed constituting a nucleus of the aggregates carrying excessive amounts of either starch or casein.     

Improvement of Synthesis and Dielectric Properties of Polyurethane/Mt-QASs<Superscript>+</Superscript> (Novel Synthesis)

Polyurethane-based nanocomposites were prepared and their dielectric properties were characterized. Polyurethane (PU) composites were prepared with different organoclay content (1, 3, 5, and 10 wt% for all cases). The composites included quaternary ammonium salts such as 1-methyl-di-octyl-1 phenyl ammonium iodide (QAS-1), 1-methyl-di-nonyl-1 phenyl ammonium iodide (QAS-2), and 1-methyl-di-dodecyl-1 phenyl ammonium iodide (QAS-3) which were newly synthesized for modification of Na⁺-montmorillonite. Addition of aluminum silicate enhanced the dielectric properties at a constant concentration. Dielectric constants of nanocomposites compounded with 3 %- and 5 %-organoclay were close in value. The characterization of PU/organoclay composites was carried out using Fourier transform infrared and X-ray diffraction.     

Biostabilization of municipal solid waste

A mechanical-biological process for municipal solid waste (MSW) treatment was monitored for one year. Mechanical pre-treatment provided two fractions. The oversize fraction (diameter > 50 mm) (yield of 600 g kg(-1) ww) (46 Mg day(-1)) was used for refuse derived fuel production, after undergoing a mechanical refining processes, because of low moisture content (200-250 g kg(-1)) and high calorific value (2500-2800 kcal kg ww(-1)). The undersize fraction (diameter < 50 mm) (yield 400 g kg(-1) ww) (30 Mg day(-1)) contained about 800 g kg(-1) of the MSW organic matter. This fraction was biologically treated using an aerobic process with an organic waste fraction from separate collection (77 Mg day(-1)) and recycled stabilized material (62 Mg day(-1)) obtained from end-product sieve (diameter < 20 mm) used as bulking agent. A retention time of three weeks was sufficient to obtain stabilized products in agreement with up-dated rules of the Lombardy Region (North Italy) regarding biostabilization and composting processes. Dynamic Respiration Index (DRI), such as required by both Lombardy Region rules and suggested by the European Community, was chosen in preference to other indices in order to assess the degree of biological stability of the end products. A mean DRI value of 1164 mg O2 kg SV(-1) h(-1) was obtained and is in agreement with the proposed limit of 1000+/-200 mg O2 kg SV(-1) h(-1). Self-heating test, potential biogas production and fermentable volatile solids were also used as parameters to describe the potential impact of treated waste, providing further useful information. Nevertheless, all of these methods revealed analytical or interpretative limits. A complete mass balance of the biological treatment section showed that, from a net input of 107 Mg day(-1), only 250 g kg(-1) (27 Mg day(-1)) of the waste needed to be landfilled, with 750 g kg(-1) (80 Mg day(-1)) being lost as CO2 and H2O.     

Morphological Changes in Poly(Caprolactone)/Poly(Vinyl Chloride) Blends Caused by Biodegradation

The biodegradation of blends of poly(caprolactone) (PCL) and poly(vinyl chloride) (PVC) has been studied. Blends of composition PCL/PVC 1:1 and 1:2 w/w were tested. The 1:1 blend contained crystals in the as-cast state and became more crystalline on exposure to different bio-active agents. The 1:2 blend was amorphous in the as-cast state but developed a significant crystal component after 4 months exposure to the bio-agents. Three bio-active agents were used and all were found to produce qualitatively similar behaviour but their activity was somewhat different. For both the 1:1 blend and the 1:2 blend the ranking of the three bio-active agents tested, in increasing order, was Curvularia sp.; Trogia buccinalis; Phanerochaete chrysosporium.     

Degradation of petroleum hydrocarbons from bottom sludge of crude oil storage tanks using in-vessel composting followed by oxidation with hydrogen peroxide and Fenton

In this research the feasibility of aerated in-vessel composting process followed by chemical oxidation with H₂O₂ and Fenton for removal of petroleum hydrocarbons from oily sludge of crude oil storage tanks was investigated. The ratios of the sludge to immature compost were 1:0 (as abiotic control), 1:2, 1:4, 1:6, 1:8 and 1:10 (as dry basis) at a C:N:P ratio of 100:5:1 and 55 % moisture content for a period of 10 weeks. Six concentrations of H₂O₂ and Fenton were added to the compost mixture for a period of 24- and 48-h reaction times. Results showed that petroleum hydrocarbons removal in ratios of 1:2, 1:4, 1:6, 1:8 and 1:10 were 66.6, 73.2, 74.8, 80.2 and 79.9 %, respectively. The results of the abiotic experiments indicated that the main mechanism of hydrocarbon removal in the composting reactors was biological. The application of combined composting and chemical oxidation demonstrated a remarkable (about 88 %) overall removal. The study showed that in-vessel composting combined with chemical oxidation is a viable choice for the remediation of the sludge.     

Nitrogen Budget of a Spruce Forest Ecosystem After Six-year Addition of Ammonium Sulphate in Southwest Sweden

A nitrogen (N) budget was constructed for a period of 6 years (1988–1993) in a Norway spruce stand with current deposition of 19 kg N and 22 kg S ha⁻¹ year⁻¹. The stand was fertilized annually by addition of 100 kg N and 114 kg S ha⁻¹ (NS). Above and below ground biomass, litterfall, fine- root litter production, soil solution and net mineralization were measured to estimate pools, fluxes and accumulation of nitrogen. The average needle litterfall in control (C) and NS plots in 1993 was 2.2 and 2.5 ton ha⁻¹ year⁻¹, respectively. The fine root litter production prior to treatment (1987) was 4.4 ton ha⁻¹ year⁻¹ and after treatment (1993) it was 4.5 and 3.9 ton ha⁻¹ year⁻¹ in C and NS plots, respectively. Net N mineralization in the soil profile down to 50 cm was estimated to be 86 and 115 kg ha⁻¹ year⁻¹ in C and NS plots, respectively in 1992. During the treatment period the uptake of N in the needle biomass in C and NS plots was 29 and 77 kg ha⁻¹ year⁻¹, respectively. No N was accumulated in needles of C plot where the NS plots accumulated 34 kg ha⁻¹ year⁻¹. Of the annually added inorganic N to NS plots 47% was accumulated in the above and below ground biomass and 37% in the soil. N fluxes via fine-root litter production in the C plots were much higher (54 kg ha⁻¹ year⁻¹) than that via litterfall (29 kg ha⁻¹ year⁻¹). The corresponding values in the NS plots were 65 and 43 kg ha⁻¹ year⁻¹, respectively. Most of the net N mineralization occurred in the FH layer and upper mineral soil. It is concluded that fine root litter and litterfall play an important role in the cycling of N. Despite a high N uptake the losses of N in litterfall and fine root litter resulted in an incorporation of N in soil organic matter.     

分子筛催化剂生产废水的生物处理

采用氨化—硝化—反硝化三段联合生物工艺处理分子筛催化剂生产过程中产生的含有机胺废水。实验结果表明：在氨化过程中,当进水COD稳定为1 200~1 600 mg/L时,出水COD低于300 mg/L,COD去除率稳定在80%左右,当进水ρ（有机氮）为100~160 mg/L时,出水ρ（有机氮）均低于30 mg/L,有机氮去除率大于80%,在整个氨化过程中,出水ρ（氨氮）较进水ρ（氨氮）提高了35~200 mg/L;硝化过程中,当进水ρ（氨氮）小于等于300 mg/L时,出水ρ（氨氮）最终稳定在15 mg/L以内,氨氮去除率大于90%;在反硝化过程中,亚硝酸盐氮去除率基本稳定在98%以上,最终出水COD低于80 mg/L,出水ρ（总氮）低于25 mg/L。     

Eco-Friendly Synthesis and Antimicrobial Performance of New Heteropolymer Composites

Journal of Polymers and the Environment - Heteropolymeric materials of resorcinol, aniline, urea, and formaldehyde are synthesized by 1:1:1:3 molar ratios of the respective monomers with different...     

Microbiological characterization and specific methanogenic activity of anaerobe sludges used in urban solid waste treatment

This study presents the microbiological characterization of the anaerobic sludge used in a two-stage anaerobic reactor for the treatment of organic fraction of urban solid waste (OFUSW). This treatment is one alternative for reducing solid waste in landfills at the same time producing a biogas (CH(4) and CO(2)) and an effluent that can be used as biofertilizer. The system was inoculated with sludge from a wastewater treatment plant (WWTP) (Río Frío Plant in Bucaramanga-Colombia) and a methanogenic anaerobic digester for the treatment of pig manure (Mesa de los Santos in Santander). Bacterial populations were evaluated by counting groups related to oxygen sensitivity, while metabolic groups were determined by most probable number (MPN) technique. Specific methanogenic activity (SMA) for acetate, formate, methanol and ethanol substrates was also determined. In the acidogenic reactor (R1), volatile fatty acids (VFA) reached values of 25,000 mg L(-1) and a concentration of CO(2) of 90%. In this reactor, the fermentative population was predominant (10(5)-10(6)MPN mL(-1)). The acetogenic population was (10(5)MPN mL(-1)) and the sulphate-reducing population was (10(4)-10(5)MPN mL(-1)). In the methanogenic reactor (R2), levels of CH(4) (70%) were higher than CO(2) (25%), whereas the VFA values were lower than 4000 mg L(-1). Substrate competition between sulphate-reducing (10(4)-10(5)MPN mL(-1)) and methanogenic bacteria (10(5)MPN mL(-1)) was not detected. From the SMA results obtained, acetoclastic (2.39 g COD-CH(4)g(-1)VSS(-1)day(-1)) and hydrogenophilic (0.94 g COD-CH(4)g(-1)VSS(-1)day(-1)) transformations as possible metabolic pathways used by methanogenic bacteria is suggested from the SMA results obtained. Methanotrix sp., Methanosarcina sp., Methanoccocus sp. and Methanobacterium sp. were identified.     

Effect of compost application rate on carbon degradation and retention in soils

We investigated the effect of a single compost application at two rates (50 and 85Mgha(-1)) on carbon (C) degradation and retention in an agricultural soil cropped with maize after 150d. We used both C mass balance and soil respiration data to trace the fate of compost C. Our results indicated that compost C accumulated in the soil after 150d was 4.24Mgha(-1) and 6.82Mg C ha(-1) for 50 and 85Mg ha(-1) compost rate, respectively. Compost C was sequestered at the rate of 623 and 617g C kg(-1) compost TOC for 50 and 85Mgha(-1) compost dose, respectively. These results point to a linear response between dose of application and both C degradation and retention. The amount of C sequestered was similar to the total recalcitrant C content of compost, which was 586g C kg(-1) compost TOC, indicating that, probably, during the short experiment, the labile C pool of compost (414g C kg(-1) of compost TOC) was completely degraded. Soil respiration measured at different times during the crop growth cycle was stable for soils amended with compost (CO2 flux of 0.96+/-0.11g CO2 m(-2) h(-1) and 1.07+/-0.10g CO2 m(-2) h(-1), respectively, for 50 and 85Mgha(-1)), whereas it increased in the control. The CO2 flux due to compost degradation only, though not statistically significant, was always greatest for the highest compost doses applied (0.22+/-0.40g CO2 m(-2) h(-1) and 0.33+/-0.25g CO2 m(-2) h(-1) for the 50 and 85Mgha(-1) compost dose, respectively). This seems to confirm the highest C degradation for the 85Mgha(-1) compost dose as a consequence of the presence of more labile C. Unlike other studies, the results show a slight increase in the fraction of carbon retained with the increase in compost application rate. This could be due to the highly stable state of the compost prior to application, although it could also be due to sampling uncertainty. Further investigations are needed to better explain how the compost application rate affects carbon sequestration, and how characterization into labile and recalcitrant C can predict the amount of C sequestered in the soil.     

Hazardous medical waste generation rates of different categories of health-care facilities

Goal of this work was to calculate the hazardous medical waste unit generation rates (HMWUGR), in kg bed(-1)d(-1), using data from 132 health-care facilities in Greece. The calculations were based on the weights of the hazardous medical wastes that were regularly transferred to the sole medical waste incinerator in Athens over a 22-month period during years 2009 and 2010. The 132 health-care facilities were grouped into public and private ones, and, also, into seven sub-categories, namely: birth, cancer treatment, general, military, pediatric, psychiatric and university hospitals. Results showed that there is a large variability in the HMWUGR, even among hospitals of the same category. Average total HMWUGR varied from 0.012 kg bed(-1)d(-1), for the public psychiatric hospitals, to up to 0.72 kg bed(-1)d(-1), for the public university hospitals. Within the private hospitals, average HMWUGR ranged from 0.0012 kg bed(-1)d(-1), for the psychiatric clinics, to up to 0.49 kg bed(-1)d(-1), for the birth clinics. Based on non-parametric statistics, HMWUGR were statistically similar for the birth and general hospitals, in both the public and private sector. The private birth and general hospitals generated statistically more wastes compared to the corresponding public hospitals. The infectious/toxic and toxic medical wastes appear to be 10% and 50% of the total hazardous medical wastes generated by the public cancer treatment and university hospitals, respectively.     

Evaluation of batch anaerobic co-digestion of palm pressed fiber and cattle manure under mesophilic conditions

Palm pressed fiber (PPF) and cattle manure (CM) are the waste which can be managed properly by anaerobic co-digestion. The biogas production in co-digested PPF and CM at three volatile solids (VS) ratios of 3:1, 1:1, and 1:3 was investigated in a series of batch experiments at an organic loading rate of 30.0 g VS/L under mesophilic (37 ± 1 °C) conditions. The highest daily biogas yield of PPF and CM only, was 90.0 mL/g VS_added at day 12 and 23.4 mL/g VS_added at day 7. For co-digestion of PPF/CM at mixing ratios of 3:1, 1:1 and 1:3, there were 93.6 mL/g VS_added at day 11, 86.8 and 26.4 mL/g VS_added at day 8. VS removal rate for PPF, CM, and co-digestion at mixing ratio of 3:1, 1:1, and 1:3 were 91.1%, 86.0% and 71.0%, respectively. The anaerobic digestion of PPF and CM and their co-digestion systems were stable in operation with low range of volatile fatty acids (VFA)/TIC (total inorganic carbon) of (0.035–0.091). The main volatile fatty acids were propionic, and iso-butyric acids for PPF, iso-butyric and n-butyric acids for CM. The VFAs and ammonium inhibition were not occurred. The modified Gompertz model can be used to perform a better prediction with a lower difference between the measured and predicted biogas yields. A VS ratio of 3:1 is recommended for practice.     

废聚碳酸酯水解法制双酚A

以1,4-二氧六环为溶剂、NaOH为催化剂,采用废聚碳酸酯(PC)常压水解法制双酚A(BPA).对反应影响因素进行了研究.实验结果表明,在反应温度为100℃、反应时间为8h、m(NaOH):m(水+溶剂)=1:33、m(溶剂):m(PC)=4:1、m(水):m(PC)=1:1的最佳反应条件下,PC水解率大于98%,BPA收率大于95%.     

Methane oxidation in water-spreading and compost biofilters.

This study evaluated two biofilter designs to mitigate methane emissions from landfill vents. Water-spreading biofilters were designed to use the capillarity of coarse sand overlain by a finer sand to increase the active depth for methane oxidation. Compost biofilters consisted of 238-L barrels containing a 1:1 mixture (by volume) of compost to expanded polystyrene pellets. Two replicates of each type of biofilter were tested at an outdoor facility. Gas inflow consisted of an approximately 1:1 mixture (by volume) of CH4 and CO2. Methane output rates (J(out); g m(-2) day(-1)) were measured using the static chamber technique and the Pedersen et al. (2001) diffusion model. Methane oxidation rate (J(ox); g m(-2) day(-1)) and fraction of methane oxidized (f(ox)) were determined by mass balance. For methane inflow rates (J(in)) between 250 and 500 g m(-2) day(-1), the compost biofilter J(ox), 242 g m(-2) day(-1), was not significantly different (P = 0.0647) than the water-spreading biofilter J(ox), 203 g m(-2) day(-1); and the compost f(ox), 69%, was not significantly different (P = 0.7354) than water-spreading f(ox), 63%. The water-spreading biofilter was shown to generally perform as well as the compost biofilter, and it may be easier to implement at a landfill and require less maintenance.     

化工废气排放量灰色预测的GPSM（1）模型

在对ＧＩＭ（１）模型研究的基础上，提出了一种化工废气排放的单变量灰色幂级数曲线预测新模型「简称（ＧＰＳＭ（１）」，并建立了辨识模型参数的优化方法。结果表明，ＧＰＳＭ（１）在有线性输出的平稳系统中，比ＧＭ（１，１）更能反映原始资料提供的信息，系统分辨率高，同态性好，预测精度理想，为环境系统的拟合、预测分析和决策开辟了新途径，从而拓宽了ＧＭ（１，１）模型在环境科学领域中的应用范围。     

Integrated biogas technology in the tropics. 2. Use of slurry for fish culture

The composite slurry from four 3.5-m³ ferrocement digesters fed a mixture of nightsoil, water hyacinth (Eichhornia crassipes) and rice straw was loaded into four 200-m² earth fish ponds at organic loading rates of 25, 50, and 100 kg chemical oxygen demand (COD) ha⁻¹ day⁻¹. Impressive extrapolated net fish yields of about 10 kg ha⁻¹ day⁻¹ (3.7 ton ha⁻¹ year⁻¹) were obtained at the highest organic loading rate, equivalent to loading rates of about 120 kg total solids and 4.5 kg total Kjeldahl nitrogen ha⁻¹ day⁻¹. There may be potential for even greater yields from biogas slurry fed fish ponds because the relationship between net fish yield and slurry loading rate was linear. Constraints in the development of integrated biogas technology for poor farmers in the tropics are likely to be associated with the digester rather than with the reuse of slurry for fish culture.     

Mechanically-biologically treated municipal solid waste as a support medium for microbial methane oxidation to mitigate landfill greenhouse emissions

The residual fraction of mechanically-biologically treated municipal solid waste (MBT residual) was studied in the laboratory to evaluate its suitability and environmental compatibility as a support medium in methane (CH(4)) oxidative biocovers for the mitigation of greenhouse gas emissions from landfills. Two MBT residuals with 5 and 12 months total (aerobic) biological stabilisation times were used in the study. MBT residual appeared to be a favourable medium for CH(4) oxidation as indicated by its area-based CH(4) oxidation rates (12.2-82.3 g CH(4) m(-2) d(-1) at 2-25 degrees C; determined in CH(4)-sparged columns). The CH(4) oxidation potential (determined in batch assays) of the MBT residuals increased during the 124 d column experiment, from <1.6 to a maximum of 104 microg CH(4) g(dw)(-1) h(-1) (dw=dry weight) at 5 degrees C and 578 microg CH(4) g(dw)(-1) h(-1) at 23 degrees C. Nitrous oxide (N(2)O) production in MBT residual (<15 microg N(2)O kg(dw)(-1) d(-1) in the CH(4) oxidative columns) was at the lower end of the range of N(2)O emissions reported for landfills and non-landfill soils, and insignificant as a greenhouse gas source. Also, anaerobic gas production (25.6 l kg(dw)(-1) during 217 d) in batch assays was low, indicating biological stability of the MBT residual. The electrical conductivities (140-250 mS m(-1)), as well as the concentrations of zinc (3.0 mg l(-1)), copper (0.5 mg l(-1)), arsenic (0.3 mg l(-1)), nickel (0.1 mg l(-1)) and lead (0.1 mg l(-1)) in MBT residual eluates from a leaching test (EN-12457-4) with a liquid/solid (L/S) ratio of 10:1, suggest a potential for leachate pollutant emissions which should be considered in plans to utilise MBT residual. In conclusion, the laboratory experiments suggest that MBT residual can be utilised as a support medium for CH(4) oxidation, even at low temperatures, to mitigate greenhouse gas emissions from landfills.     

Fluxes of NO3-, NH4+, NO,NO2, and N2O in an Old Danish Beech Forest

The fluxes of the major nitrogen compounds havebeen investigated in many ecosystem studies over the world.However, only in few studies has attention been drawn to theimportance of the fluxes of minor gaseous nitrogen compoundsto complete the nitrogen cycle. In Denmark a detailed study onthe nitrogen cycle in an old beech forest has been implementedin 1997 at Gyrstinge near Sorø, Zealand. The study includesthe fluxes of the gases NO, N₂O and water mediatedtransport of NO₃ ^- and NH₄ ⁺. Measurementsof the fluxes of the gaseous compounds are performed withmicro-meteorological methods (eddy-correlation and gradient)and with chambers. Water mediated fluxes encompass rain,throughfall, stem-flow and leaching from the root zone. Thehydrological model is verified by TDR measurements. The findings show that the total water mediated N input tothe forest floor with throughfall and stemflow was 25.6 kg Nha^-1 yr ^-1, and open field wet deposition withprecipitation was 19.0 kg N ha^-1 yr ^-1. The internalcycling of N in the ecosystem measured as turnover oflitterfall and plant uptake was 100 kg N ha^-1 yr ^-1and 14 kg N ha^-1 yr ^-1, respectively. The fluxes ofthe gaseous N compounds NO and N₂O were of minorimportance for the total N turnover in the forest, NO_xemission being <1 kg N ha^-1 yr ^-1 and N₂Oemission from the soil being 0.5 kg N ha^-1 yr ^-1 withno significant difference between wet and dry soils.Concentrations of NO₃ ^- and NH₄ ⁺ in thesoil solution beneath the rooting zone are very small andconsequently the N leaching is almost negligible. It isconcluded that the nitrogen mass balance of this old beechforest ecosystem mainly is controlled by the input by dry andwet deposition and a large internal N cycle with a fast litterturnover. The nitrogen input tothe forest ecosystem which currently exceeds the critical loadby 5 kg N ha^-1 yr ^-1is mainly accumulated in the soil and no significant nitrateleaching is occurring.     

用新型絮凝剂处理制浆漂白废水

采用一种新型的有机无机复合型高分子絮凝剂(F-1)处理制浆漂白废水，进行了絮凝条件的优选试验和对比试验，结果表明：F-1絮凝剂的絮凝沉降效果与絮凝剂的用量、废水的pH有很大的关系。当废水的pH为6．0、絮凝剂用量为100mg／L时，漂白废水的色度、SS和COD的去除率分别为98．2％、93．6％和78．6％。而且，其絮凝性能明显优于阳离子聚丙烯酰胺(PAMC)、聚合氯化铝(PAC)以及聚合硫酸铁(PFS)等絮凝剂。