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121.
CO2资源化利用的现状及前景   总被引:6,自引:2,他引:4  
介绍了CO2分离捕集最新工艺——电化学法、膜法、化学循环燃烧法的研究进展。评述分析了CO2的各种资源化应用前景:CO2气体用作生物碳源、辅助注射成型剂及有机物(如氨基甲酸酯、表面活性剂)合成原料等;液态CO2用于人造金刚石、热泵干燥、超临界CO2萃取及固体干冰冷喷射清洗等。CO2作为一种潜在的丰富碳源,应不断研发其新的应用领域,加快其工业化应用。  相似文献   
122.
通过建立地下水数学模型,回答了土壤渗滤工程运行控制中的两个难点问题:(1)工程运行水力负荷.当工程地块周边存在河流时,河流水位低时,有助于增加水力负荷,反之则降低水力负荷;实际土壤运行面积的增加和独立运行单元之间的间距增加也能够增加工程运行水力负荷.(2)地下水水质监测井的优化布设.模拟工程运行后地下水水质空间分布特征,在地下水水质最不利的位置和其他特别关注的位置布置监测井,从而能够以具有典型代表性且数目较少的监测井达到准确评估工程对地下水水质影响的目的.  相似文献   
123.
肖莉  边建东  王昕  施力 《化工环保》2006,26(6):514-517
采用溶胶-凝胶法制备锌铝助剂,该助剂于700℃焙烧后与流化催化裂化(FCC)催化剂进行机械混合,制得混合催化剂;在FCC烟气工业模拟装置上考察混合催化剂的脱硫活性,用混合催化剂的脱硫活性来反映锌铝助剂的脱硫性能。实验结果表明,氧化锌质量分数为10%的锌铝助剂的脱硫活性最佳,脱硫率达62.5%。采用红外光谱和X射线衍射(XRD)对锌铝助剂的脱硫机理进行了研究,红外分析结果表明,弱的L酸中心有利于锌铝助剂脱硫,XRD分析结果表明,锌铝助剂在锌铝尖晶石结构尚未完全形成时,存在较多的晶格缺陷,能够有效地吸附烟气中的SOx,将其转化为H2S。  相似文献   
124.
Environmental Science and Pollution Research - In this study, Mn-doped MgAl-layered double hydroxides (LDHs) were successfully synthesized for efficient removal arsenate from aqueous solution. The...  相似文献   
125.
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   
126.
ABSTRACT

Interaction of environmental pollution between peripheral areas has become a central topic in the field of resources and environment but little is known about the actual impact on peripheral areas in the current literature. This paper sets out a simultaneous equation model to investigate the spillover effect of environmental pollution between China’s peripheral areas utilizing the panel data of 218 cities in China. Making use of indicators for measuring the impact on environmental pollution, it identifies that environmental pollution between cities of China has a significant two-way spillover effect. After standardization of variables, it is found that the spillover effect of peripheral areas on urban environmental pollution cannot be neglected. Nearly, a third of the environmental pollution level in a city is induced by the environmental pollution in peripheral areas. If the indicator of environmental pollution in peripheral areas is missing, wrong conclusions will be drawn. Therefore, government should shift the emphasis of environmental regulation from local to global, and improve the overall environmental quality through coordinated management of regional environment.  相似文献   
127.
Russian Journal of Ecology - The present study was conducted to investigate the n-alkane composition of typical alpine meadows. Plant and soil samples were collected and analyzed to characterize...  相似文献   
128.
Wang  Jiaqing  Lu  Pei  Su  Wei  Xing  Yi  Li  Rui  Li  Yuran  Zhu  Tingyu  Yue  Huifang  Cui  Yongkang 《Environmental science and pollution research international》2019,26(20):20248-20263

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.

  相似文献   
129.
Chen  Hui  Mao  Wei  Shen  Yiqiu  Feng  Weiwei  Mao  Guanghua  Zhao  Ting  Yang  Lanqin  Yang  Liuqing  Meng  Chunfeng  Li  Yong  Wu  Xiangyang 《Environmental science and pollution research international》2019,26(24):24609-24619

Phthalates (PAEs) in drinking water sources such as the Yangtze River in developing countries had aroused widespread concern. Here, the water, suspended particulate matter (SPM), and sediment samples were collected from 15 sites in wet and dry seasons in Zhenjiang, for the determination of six PAEs (DMP, DEP, DIBP, DBP, DEHP, and DOP) using the solid-phase extraction (SPE) or ultrasonic extraction coupled with gas chromatography-mass spectrometry (GC-MS). The total concentrations of six PAEs (Σ6PAEs) spanned a range of 2.65–39.31 μg L?1 in water, 1.97–34.10 μg g?1 in SPM, and 0.93–34.70 μg g?1 in sediment. The partition coefficients (Kd1) of PAEs in water and SPM phase ranged from 0.004 to 3.36 L g?1 in the wet season and from 0.12 to 2.84 L g?1 in the dry season. Kd2 of PAEs in water and sediment phase was 0.001–9.75 L g?1 in the wet season and 0.006–8.05 L g?1 in the dry season. The dominant PAEs were DIBP, DBP, and DEHP in water and SPM, DIBP, DEHP, and DOP in sediment. The concentration of DBP in water exceeded the China Surface Water Standard. The discharge of domestic sewage and industrial wastewater might be the main potential sources of PAEs. The risk quotient (RQ) method used for the risk assessment revealed that DBP (0.01 < RQ < 1) posed a medium risk, while DIBP and DEHP (RQ > 1) posed a high environmental risk in water, DIBP (RQ > 1) also showed a high risk in sediment.

  相似文献   
130.
安选军  王黎  张霖  邵鹏程  何兴 《化工环保》2007,27(4):364-366
针对聚α-烯烃合成油(PAO)生产旧工艺存在的问题,介绍了以固载化AlCl3为催化剂的PAO生产新工艺,考察了各种因素对PAO收率的影响。实验结果表明,在反应温度为100℃、反应时间为8h、A1C1,与α-烯烃质量比为10:75的条件下,PAO收率为48.8%。采用新工艺后,PAO产品质量有了明显提高,黏度指数为132,碱和白土的消耗为零,且没有废渣产生,可实现清洁化生产。  相似文献   
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