Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts’ surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results.
Environmental Science and Pollution Research - Suicide prevention has become a public health issue of great concern. Previous studies proved that ambient temperature had an impact on suicide death,... 相似文献
Papillary thyroid cancer (PTC) has inflicted huge threats to the health of mankind. Metal pollution could be a potential risk factor of PTC occurrence, but existing relevant epidemiological researches are limited. The current case-control study was designed to evaluate the relationships between exposure to multiple metals and the risk of PTC. A total of 262 histologically confirmed PTC cases were recruited. Age- and gender-matched controls were enrolled at the same time. Urine samples were used as biomarkers to reflect the levels of environmental exposure to 13 metals. Conditional logistic regression models were adopted to assess the potential association. Single-metal and multi-metal models were separately conducted to evaluate the impacts of single and co-exposure to 13 metals. The increased concentration of urinary Cd, Cu, Fe, and Pb quartiles was found significant correlated with PTC risk. We also found the decreased trends of urinary Se, Zn, and Mn quartiles with the ORs for PTC. These dose-response associations between Pb and PTC were observed in the single-metal model and remained significant in the multi-metal model (OR25-50th=1.39, OR50-75th=3.32, OR>75th=7.62, p for trend <0.001). Our study suggested that PTC was positively associated with urinary levels of Cd, Cu, Fe, Pb, and inversely associated with Se, Zn, and Mn. Targeted public health policies should be made to improve the environment and the recognition of potential risk factors. These findings need additional studies to confirm in other population.
Environmental Science and Pollution Research - Drinking water containing environmental endocrine disruptor compounds (EDCs) endangers human health, and researching the purification process of... 相似文献
Environmental Science and Pollution Research - Nitrosamines (NAms) are potent genotoxic and carcinogenic but widely detected in drinking water. This study aimed to investigate the occurrence of... 相似文献
Environmental Science and Pollution Research - The effect of air staging strategies on NOx control was investigated on a 210-kW small-scale biomass boiler (SBB) and a 1.4-MW medium-scale biomass... 相似文献
With the rapid economic development in China, the amount of plastic waste (PW) generated has greatly increased and much of the waste is currently not treated. To reduce greenhouse gas (GHG) emissions from recycling of PW, we estimated the PW flow and considered methods to improve the household PW recycling system in Tianjin by adjusting processes during transportation and establishing a PW recycling factory in Zi’ya Industrial Park. The goal of the study was to identify reasonable improvements for the recycling system and clarify the environmental load. Geographic information system (GIS) technology was used to simulate transport processes for comparing GHG emissions from the transport processes between the present case and an improved case. Life cycle assessment (LCA) was used to compare GHG emissions between a projected scenario and a baseline scenario. Estimated GHG emissions during transport processes in the improved case were reduced by about 12,197 t CO2 eq per year compared to the present case, equivalent to about 65.9 % of the total emissions in the present case. GHG emissions in the projected scenario were about 101,738 t CO2 eq less per year than the baseline scenario, equivalent to about 75.5 % of the total emissions in the baseline scenario. 相似文献
Effects of carbon concentration and Cu additive in simulated fly ash (SFA) and real fly ash (RFA) on the formation of polychlorinated dibenzofurans (PCDFs), polychlorinated dibenzo-p-dioxins (PCDDs), chlorobenzenes, and polychlorinated biphenyls which were all regarded as persistent chlorinated aromatics in iron ore sintering were investigated. In the annealing process of SFA with various carbon contents, the yield of chlorinated aromatics and the I-TEQ obtained their maximum at 10 wt% carbon content. Active carbon in SFA acted as the carbon source as well as an adsorbent which led to higher production of PCDD/F in solid phase at 10 wt% carbon content. The increase of carbon content will be beneficial on the formation of 2,3,7,8-Chloro-substituted PCDF compared with 2,3,7,8-Chloro-substituted PCDD. In addition, the CuCl2·2H2O was a much more powerful catalyst in the formation of chlorinated aromatic compounds compared with elementary Cu, since it served as both a catalyst and a chlorine donor. However, the RFA behaved similarly with SFA with elementary Cu in the formation of chlorinated aromatic compounds. The effect of carbon content and copper additives on formation of 2,3,7,8-chloro-substituted congeners displayed similar characteristics with the tetra- to octa-PCDD/F isomers and even the total PCDD/Fs. 相似文献
Electro conductive hydrogels, consisting of chitosan (CS), hyaluronic acid (HA), and polypyrrole (PPy), were prepared via an in situ enzymic polymerization of pyrrole in the CS–HA hydrogel, using laccase as the catalyst. This CS–HA–PPy composite hydrogel showed good conductivity. The chemical structure and morphology of this conductive hydrogel were studied by Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction technique. For CS–HA–PPy and CH–HA hydrogel, the temperature at which fastest decomposition occurred was 260 and 244 °C, respectively. That means the thermal stability of CS–HA–PPy is better than CS–HA hydrogel. The conductive hydrogel also showed excellent swelling and deswelling behaviors. 相似文献