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排序方式: 共有1431条查询结果,搜索用时 31 毫秒
931.
选取CH4、O2、CO2、Ar、NO、NH3,等气体,作为混合气和煤粉一起送入一维沉降炉内,以模拟O2/CO2气氛下煤中燃料氮、循环NO以及二者的相互作用对NO排放的影响,结果显示,在还原性气氛下NH3、HCN、CH4、CO与循环NO间的反应是NO排放下降的主要因素,且煤焦与NO的异相反应、吸附反应对NO的降解效果要明显高于氧化性气氛,同时,CO2体积分数的增加使得燃料中氮的氧化率升高,循环NO的降解率下降;氧化性气氛下随CO2体积分数的增加,燃料中氮的氧化率也增加,但循环NO的降解率升高.当CO2体积分数不变时,其对NO降解的作用随循环NO体积分数的增加愈加明显,在循环NO也不变且CO2体积分数较低时,随过量空气系数的增加,循环NO的降解率下降,而CO2体积分数较高时则出现相反情况。 相似文献
932.
根据硫酸钠熔炼法处理废合金所得钴渣组成特点 ,通过氧化焙烧、酸分解、水解除杂、沉钴和煅烧等工序制取氧化钴。焙烧最佳工艺条件为 :NaNO3用量为钴渣量的 0 8倍 ,焙烧温度 75 0℃ ,时间 2 5h。盐酸分解、喷淋水解除铁、草酸铵沉钴和煅烧阶段钴的回收率 ( % )分别为 97 5、96 6、99 5和 99 0 ,使Co、Ta的回收率分别达到 92 78%和 85 %。 相似文献
933.
从钢铁酸洗废液制备聚合氯化铁及其应用研究 总被引:7,自引:0,他引:7
以钢铁酸洗废液和废铁屑为原料,测定了Fe^3 和Fe^2 含量,把过量的废铁屑加入钢铁酸洗废液中,使整个溶液还原成氯化亚铁溶液。采用氯酸钠氧化法,在(60~70)℃范围内经氧化、水解、聚合,然后加入一定量的稳定剂制得聚合氯化铁(PFC)溶液,讨论了影响聚合反应的主要因素。对炼油厂废水进行处理,合成的聚合氯化铁的处理效果明显优于市售聚合硫酸铁和三氯化铁。 相似文献
934.
935.
936.
Fe3++草酸盐络合物/H2O2/日光体系对垃圾渗滤液的处理 总被引:15,自引:2,他引:15
以Fe^3 草酸盐络合物/H2O2作光氧化剂,利用太阳光对垃圾渗滤液进行了光氧化降解实验。结果表明:在溶液的初始pH为3.0,H2O2投加量为460mg/L,ρ(Fe^3 )为20mg/L条件下,反应60min后,CODC4去除率可达80%左右;溶液的pH,P(H2O2)和ρ(Fe^3 )对光解过程有显著影响,而且在太阳光的照射下,CODCr去除率比在紫外光下高。在一定实验条件下,用日光/H2O2/草酸铁体系对城市垃圾渗滤液处理效果较好,可作为垃圾渗滤液的深度处理。 相似文献
937.
LI Zhe SHEN Lin-tao HUANG Wei~* XIE Ke-chang Key Laboratory of Coal Science Technology Ministry of Education Shanxi Province Taiyuan University of Technology Taiyuan China. 《环境科学学报(英文版)》2007,19(12)
The catalyst of Fe-Mo/ZSM-5 has been found to be more active than Fe-ZSM-5 and Mo/ZSM-5 separately for selective catalytic reduction (SCR) of nitric oxide (NO) with NH_3.The kinetics of the SCR reaction in the presence of O_2 was studied in this work.The results showed that the observed reaction orders were 0.74-0.99,0.01-0.13,and 0 for NO,O_2 and NH_3 at 350-450℃,respectively. And the apparent activation energy of the SCR was 65 kJ/mol on the Fe-Mo/ZSM-5 catalyst.The SCR mechanism was also deduced. Adsorbed NO species can react directly with adsorbed ammonia species on the active sites to form N_2 and H_2O.Gaseous O_2 might serve as a reoxidizing agent for the active sites that have undergone reduction in the SCR process.It is also important to note that a certain amount of NO was decomposed directly over the Fe-Mo/ZSM-5 catalyst in the absence of NH_3. 相似文献
938.
湿法吸收法处理氮氧化物废气 总被引:6,自引:0,他引:6
介绍了湿法吸收氮氧化物工业废气的方法,并对吸收液和吸收塔进行了深入的探讨和研究。 相似文献
939.
Kazuhiko Sakamoto Katsunori Kimijima Tadao Suzuki Masahiro Uchiyama Yoshikazu Hashimoto Hisao ohta Yasuaki maeda Nobutoshi Horiuchi Shin Suzuki 《环境科学学报(英文版)》1990,(1)
The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively. 相似文献
940.
Saima Noor Shamaila Sajja Sajjad Ahmed Khan Leghari Cristina Flox Saeed Ahmad 《环境科学学报(英文版)》2021,33(10):107-119
The promising solar irradiated photocatalyst by pairing of bismuth oxide quantum dots (BQDs) doped TiO2 with nitrogen doped graphene oxide (NGO) nanocomposite (NGO/BQDs-TiO2) was fabricated. It was used for degradation of organic pollutants like 2,4-dichlorophenol (2,4-DCP) and stable dyes, i.e. Rhodamine B and Congo Red. X-ray diffraction (XRD) profile of NGO showed reduction in oxygenic functional groups and restoring of graphitic crystal structure. The characteristic diffraction peaks of TiO2 and its composites showed crystalline anatase TiO2. Morphological images represent spherical shaped TiO2 evenly covered with BQDs spread on NGO sheet. The surface linkages of , , and vibrational modes are observed by Fourier transform infrared spectroscopy (FTIR) and Raman studies. BQDs and NGO modified TiO2 results into red shifting in visible region as studied in diffused reflectance spectroscopy (DRS). NGO and BQDs in TiO2 are linked with defect centers which reduced the recombination of free charge carriers by quenching of photoluminescence (PL) intensities. X-ray photoelectron spectroscopy (XPS) shows that no peak related to in NGO/BQDs-TiO2 is observed. This indicated that doping of nitrogen into GO has reduced some oxygen functional groups. Nitrogen functionalities in NGO and photosensitizing effect of BQDs in ternary composite have improved photocatalytic activity against organic pollutants. Intermediate byproducts during photo degradation process of 2,4-DCP were studied through high performance liquid chromatography (HPLC). Study of radical scavengers indicated that has significant role for degradation of 2,4-DCP. Our investigations propose that fabricated nanohybrid architecture has potential for degradation of environmental pollutions. 相似文献