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1.
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
2.
Ethyl mercaptans which commonly exist in natural gas need to be removed due to their toxic, odorous, and corrosive properties. Herein, a novel Fe2O3-modified HNbMoO6 nanosheet catalyst (Fe2O3@e-HNbMoO6) was prepared by an exfoliation-impregnation method for the ethyl mercaptans removal. In the heterojunction catalyst, e-HNbMoO6 can be excited by visible light to generate the photogenic charge and has certain adsorption property for ethyl mercaptan with hydrogen bonding (Nb-OH or Mo-OH as the hydrogen bonding donor); Fe2O3 plays the role of accelerating photogenerated electrons and holes, and enhancing the adsorption of ethyl mercaptan with another hydrogen bonding (Fe-OH as the hydrogen bonding donor and receptor). Results showed that the adsorption capacity of Fe2O3@e-HNbMoO6 is 69.9 μmol/g for ethyl mercaptan. In addition, the photocatalytic conversion efficiency of ethyl mercaptan to diethyl disulfide is nearly 100% and it is higher than that of the other Nb-Mo based photocatalysts, such as LiNbMoO6, Fe1/3NbMoO6, Ce1/3NbMoO6, TiO2-HNbMoO6, e-HNbMoO6, CeO2@e-HNbMoO6, and Ag2O@e-HNbMoO6. Under the experimental conditions, the photocatalytic conversion efficiency is greater than the adsorption efficiency over Fe2O3@e-HNbMoO6, and there is no ethyl mercaptan output in the process of adsorption and photocatalytic conversion. Fe2O3@e-HNbMoO6 heterojunction catalyst has practical value and reference significance for purifying methane gas and enhancing photocatalytic conversion of ethyl mercaptan. 相似文献
3.
The body of Information presented in this paper is directed to those Individuals concerned with the removal of NO x in combustion flue gases. A catalytic process for the selective reduction of nitrogen oxides by ammonia has been investigated. Efforts were made toward the development of catalysts resistant to SO x poisoning. Nitrogen oxides were reduced over various metal oxide catalysts in the presence or absence of SO x(SO 2 and SO 3). Catalysts consisting of oxides of base metals (for example, Fe 2O 3) were easily poisoned by SO 3, forming sulfates of the base metals. A series of catalysts which are not susceptible to the SO x poisoning has been developed. The catalysts possess a high activity and selectivity over a wide range of temperatures, 250—450°C. The catalysts were tested in a pilot plant which treated a flue gas containing 110-150 ppm NO x, 660-750 ppm SO 2, and 40-90 ppm SO 3. The pilot plant was operated at 350°C and at a space velocity of 10,000 h -1. The removal of nitrogen oxides was more than 90% for several months. A mechanism of the NO-NH 3 reaction has also been investigated. It is found that NO reacts with NH 3 at a 1:1 mole ratio in the presence of oxygen and the reaction is completely inhibited by the absence of oxygen. The experimental data show that the NO-NH 3 reaction in the presence of oxygen is represented byNO + NH 3 + 1/4 O 2 = N 2 + 3/2 H 2O. 相似文献
4.
Media depth (MD) and moisture content (MC) are two important factors that greatly influence biofilter performance. The purpose of this study was to investigate the combined effect of MC and MD on removing ammonia (NH 3), hydrogen sulfide (H 2S), and nitrous oxide (N 2O) from swine barns. Biofiltration performance of different MDs and MCs in combination based on a mixed medium of wood chips and compost was monitored. A 3 × 3 factorial design was adopted, which included three levels of the two factors (MC: 45%, 55%, and 67% [wet basis]; MD: 0.17, 0.33, and 0.50 m). Results indicated that high MC and MD could improve NH 3 removal efficiency, but increase outlet N 2O concentration. When MC was 67%, the average NH 3 removal efficiency of three MDs (0.17, 0.33, and, 0.50 m) ranged from 77.4% to 78.7%; the range of average H 2S removal efficiency dropped from 68.1–90.0% (1–34 days of the test period) to 36.8–63.7% (35–58 days of the test period); and the average outlet N 2O concentration increased by 25.5–60.1%. When MC was 55%, the average removal efficiency of NH 3, H 2S, and N 2O for treatment with 0.33 m MD was 72.8 ± 5.9%, 70.9 ± 13.3%, and –18.9 ± 8.1%, respectively; and the average removal efficiency of NH 3, H 2S, and N 2O for treatment with 0.50 m MD was 77.7 ± 4.2%, 65.8 ± 13.7%, and –24.5 ±12.1%, respectively. When MC was 45%, the highest average NH 3 reduction efficiency among three MDs was 60.7% for 0.5 m MD, and the average N 2O removal efficiency for three MDs ranged from –18.8% to –12.7%. In addition, the pressure drop of 0.33 m MD was significantly lower than that of 0.50 m MD ( p < 0.05). To obtain high mitigation of NH 3 and H 2S and avoid elevated emission of N 2O and large pressure drop, 0.33 m MD at 55% MC is recommended. Implications: The performances of biofilters with three different media depths (0.17, 0.33, and 0.50 m) and three different media moisture contents (45%, 55%, and 67% [wet basis]) were compared to remove gases from a swine barn. Using wood chips and compost mixture as the biofilters media, the combination of 0.33 m media depth and 55% media moisture content is recommended to obtain good reduction of NH3 and H2S, and to simultaneously prevent elevated emission of N2O and large pressure drop across the media. 相似文献
5.
Odor pollution is a big environmental problem caused by large-scale livestock production in China, and developing a practical way to reduce these odors is pressing. In this study, a combination of 0.2–1.0 U/mL lignin peroxidase (LiP) and one of three peroxides (H 2O 2, CaO 2, 2Na 3CO 3·3H 2O 2) was examined for its efficiency in reducing the release of eight chemicals (propionic acid, isobutyric acid, isocaproic acid, isovaleric acid, phenol, p-cresol, indole, and skatole), NH 3, H 2S, and odor intensity from pig manure. The results showed an approximately 90% reduction in p-cresol, 40–60% reduction in odor intensity, 16.5–40% reduction in indolic compounds, and 25–40% reduction in volatile fatty acids. Being the electron acceptors of LiP, 2Na 3CO 3·3H 2O 2 and CaO 2 performed better than H 2O 2 in reducing the concentration of eight chemicals, NH 3, H 2S, and odor intensity from pig manure. The effect of deodorization can last for up to 72 hr. Implications: In China, one of the major environmental problems caused by confined feeding is odor pollution, which brings a major threat to the sustainability, profitability, and growth of the livestock industry. To couple the LiP with the electron acceptors, a low–cost, simple, and feasible method for odor removal was established in this study. Based on the study results, a practical treatment method was provided for odor pollution and supply the farm operators a more flexible time to dispose treated manure. 相似文献
6.
ABSTRACT The purpose of this research was to determine the efficiency of a polymer biocover for the abatement of H 2S and NH 3 emissions from an east-central Missouri swine lagoon with a total surface area of 7800 m 2. The flux rate of NH 3, H 2S, and CH 4 was monitored continuously from two adjacent, circular ( d = 66 m) control and treatment plots using a nonintrusive, micrometeorological method during three independent sampling periods that ranged between 52 and 149 hr. Abatement rates were observed to undergo a temporal acclimation event in which NH 3 abatement efficiency improved from 17 to 54% ( p = <0.0001 to 0.0005) and H 2S abatement efficiency improved from 23 to 58% ( p < 0.0001) over a 3-month period. The increase in abatement efficiency for NH 3 and H 2S over the sampling period was correlated with the development of a stable anaerobic floc layer on the bottom surface of the biocover that reduced mass transfer of NH 3 and H 2S across the surface. Analysis of methanogenesis activity showed that the biocover enhanced the rate of anaerobic digestion by 25% when compared with the control. The biocover-enhanced anaerobic digestion process was shown to represent an effective mechanism to counteract the accumulation of methanogenic substrates in the biocovered lagoon. 相似文献
7.
A new sampling device is described for the simultaneous collection of NH 3, HNO 3, HCl, SO 2 and H 2O 2 in ambient air. The apparatus is based on air sampling by two parallel annular denuder tubes. The gases are collected by absorption in solutions present in the annulus of the denuder tubes. After a sampling time of 30 min at flow rate of 32 ℓ min −1 the solutions are extracted from the denuders and analyzed off-line. The detection limits of NH 3, HNO 3, HCL and SO 2 are in the order of 0.1–0.5 μm −3. For H 2O 2 the detection limit is 0.01 μm −3. The reproducibility is 5–10% at the level of ambient air concentrations. Comparison of this novel technique with existing methods gives satisfactory results. The compact set-up offers the possibility of field experiments without the need of extensive equipment. 相似文献
8.
A series of manganese-cerium oxide (MnO x-CeO 2) catalysts supported by Ti-bearing blast furnace slag were prepared by wet impregnation and used for low-temperature selective catalytic reduction (SCR) of NO with NH 3. The slag-based catalyst exhibited high nitrogen oxide removal (deNO x) activity and wide effective temperature range. Under the condition of NO = 500 ppm, NH 3 = 500 ppm, O 2 = 7–8 vol%, and total flow rate = 1600 mL/min, the Mn-Ce/Slag catalyst exhibited a NO conversion higher than 95% in the range of 180–260 °C. The activity of Mn/Slag catalysts was greatly enhanced with the addition of CeO 2. The results indicated that Ti-bearing blast furnace slag had suitable phase composition as good support of SCR catalyst. Implications: Ti-bearing blast furnace slag is a kind of industrial waste in China. Much slag was underused and piling up, which could cause many environmental issues, such as enormous waste of titanium and groundwater and soil contamination by heavy metals in leachates. The utilization of slag as the support of SCR catalyst will not only make use of solid waste but also cut down the NOx emitted from power plant. 相似文献
9.
Biotreatment of various ratios of H 2S and NH 3 gas mixtures was studied using the biofilters, packed with co-immobilized cells ( Arthrobacter oxydans CH8 for NH 3 and Pseudomonas putida CH11 for H 2S). Extensive tests to determine removal characteristics, removal efficiency, removal kinetics, and pressure drops of the biofilters were performed. To estimate the largest allowable inlet concentration, a prediction model was also employed. Greater than 95% and 90% removal efficiencies were observed for NH 3 and H 2S, respectively, irrespective of the ratios of H 2S and NH 3 gas mixtures. The results showed that H 2S removal of the biofilter was significantly affected by high inlet concentrations of H 2S and NH 3. As high H 2S concentration was an inhibitory substrate for the growth of heterotrophic sulfur-oxidizing bacteria, the activity of H 2S oxidation was thus inhibited. In the case of high NH 3 concentration, the poor H 2S removal efficiency might be attributed to the acidification of the biofilter. The phenomenon was caused by acidic metabolite accumulation of NH 3. Through kinetic analysis, the presence of NH 3 did not hinder the NH 3 removal, but a high H 2S concentration would result in low removal efficiency. Conversely, H 2S of adequate concentrations would favor the removal of incoming NH 3. The results also indicated that maximum inlet concentrations (model-estimated) agreed well with the experimental values for space velocities of 50–150 h −1. Hence, the results would be used as the guideline for the design and operation of biofilters. 相似文献
10.
A series of lead dioxide electrodes developed on titania nanotube arrays with different matrix were fabricated by electrodeposition. Before the deposition of PbO 2, the matrix of this anode was electrochemically reduced in (NH 4) 2SO 4 solution and/or pre-deposited with certain amounts of copper. To gain insight into these pretreatments, the PbO 2 electrodes were characterized by SEM, LSV, and XRD, and their electrocatalytic activities for pollutant degradation were compared using p-nitrophenol ( p-NP) as a model. It was confirmed that the electrochemical reduction with (NH 4) 2SO 4 resulted in the partial conversion of TiO 2 into Ti 4O 7 and Ti 5O 9, which increased the conductivity of PbO 2 anode, but decreased its electrochemical activity, while the Ti/TNTs*-Cu/PbO 2 electrode with both pretreatments possessed the highest oxygen evolution overpotential of 2.5 V (vs. SCE) and low substrate resistance. After a 180-min treatment on this electrode, the removal efficiency of p-NP reached 82.5 % and the COD removal achieved 42.5 % with the energy consumption of 9.45 kWh m ?3, demonstrating the best performance among these electrodes with different matrices. Therefore, this titania nanotube array-based PbO 2 electrode has a promising application in the industrial wastewater treatment. 相似文献
11.
Impacts of diazinon ( O, O-diethyl O-2-isopropyl-6-methylpyrimidin-4-yl phosphorothioate), imidacloprid [1-(6-chloro-3-pyridylmethyl)- N-nitroimidazolidin-2-ylideneamine] and lindane (1,2,3,4,5.6-hexachlorocyclohexane) treatments on ammonium, nitrate, and nitrite nitrogen and nitrate reductase enzyme activities were determined in groundnut ( Arachis hypogaea L.) field for three consecutive years (1997 to 1999). Diazinon was applied for both seed- and soil-treatments but imidacloprid and lindane were used for seed treatments only at recommended rates. Diazinon residues persisted for 60 days in both the cases. Average half-lives (t 1/2) of diazinon were found 29.3 and 34.8 days respectively in seed and soil treatments. In diazinon seed treatment, NH 4 +, NO 3 ?, and NO 2 ? nitrogen and nitrate reductase activity were not affected. Whereas, diazinon soil treatment indicated significant increase in NH 4 +-N in a 1-day sample, which continued until 90 days. Some declines in NO 3 ?N were found from 15 to 60 days. Along with this decline, significant increases in NO 2 ?N and nitrate reductase activity were found between 1 and 30 days. Imidacloprid and lindane persisted for 90 and 120 days with average half-lives (t 1/2) of 40.9 and 53.3 days, respectively. Within 90 days, imidacloprid residues lost by 73.17% to 82.49% while such losses for lindane residues were found 78.19% to 79.86 % within 120 days. In imidacloprid seed-treated field, stimulation of NO 3 ?N and the decline in NH 4 +NO 2 ?-N and nitrate reductase enzyme activity were observed between 15 to 90 days. However, lindane seed treatment indicated significant increases in NH 4 +-N, NO 2 ?-N and nitrate reductase activity and some adverse effects on NO 3 ?N between 15 and 90 days. 相似文献
12.
以锐钛矿型二氧化钛和钛钨粉(5%WO3-TiO2)为载体,制备了系列钒和钨负载量不同的钒钛催化剂,考察碱金属和碱土金属(钾、钠和钙)对催化剂在氨选择性催化还原(NH3-SCR)氮氧化物反应中催化活性的影响。钾、钠和钙对钒钛催化剂的中毒影响大小顺序为钾钠钙。提高钒钛催化剂中钒的含量可显著提高催化剂的SCR活性和抗碱金属中毒性能,但高钒负载量(4.5%V2O5)造成催化剂氮气选择性明显下降,氧化亚氮生成显著增加。钨的添加有利于提高钒钛催化剂的低温活性和抗碱金属中毒性能,对氮气选择性无明显影响。 相似文献
13.
A series of iron–manganese oxide catalysts supported on TiO 2 and titanium nanotubes (TNTs) were studied for low temperature selective catalytic reduction (SCR) of NO with NH 3 in the presence of SO 2. The results showed that the specific surface area and the amount of Brønsted acid sites were highly correlated. The results also demonstrated that higher Mn 4+/Mn 3+ ratios and larger specific surface areas might be the main reasons for the excellent performance of MnFe-TNTs catalyst after SO 2 poisoning. The SO 2 poisoning effect could be minimized by reducing the GHSV, increasing the reaction temperature, or increasing the [NH 3]/[NO] molar ratio. The results also indicated that the formation of ammonium sulfate had a stronger effect on the NO conversion efficiency as compared to the formation of metal sulfate. Thus operating the low temperature SCR at above 230 oC to avoid the formation of ammonium sulfate would be the priority choice when SO 2 poisoning is a concerned issue.? Implications: Low-temperature selective catalytic reduction (SCR) has attracted increasing attention due to that it can reduce the energy consumption for the SCR process employed in industries such as steel plants and glass manufacturing plants. However, it also suffers from the sulfur dioxide (SO 2) poisoning problem. This study investigates the possibility of using titania nanotubes (TNTs) as the support of Mn/Fe bimetal oxide catalysts for low-temperature SCR to reduce the SO 2 poisoning. The results indicated that the MnFe-TNT catalyst can tolerate SO 2 for a longer time as compared with the MnFe-TiO 2 catalyst. 相似文献
14.
Ammonia emission during composting results in anthropogenic odor nuisance and reduces the agronomic value of the compost due to the loss of nitrogen. Adjusting the operating parameters during composting is an emerging in situ odor control technique that is cheap and highly efficient. The effects of in situ NH3 emission control were investigated in this study by simultaneously adjusting key operating parameters (such as C/N ratio, aeration rate, and moisture content) during the composting processes (C1–C9). Results showed that the average NH3 emission concentrations for different treatments were in the order of C1 > C4 > C2 > C5 > C3 > C6 > C7 > C8 > C9. The total content of NH3 emission (21.02 g/kg) in C9 (C/N ratio = 35, aeration rate = 15 L/min, and moisture content = 60%) was much lower than that (65.95 g/kg) in C1 (C/N ratio = 15, aeration rate = 5 L/min, and moisture content = 60%). The nitrogen loss ratio was 27.36% for C1, while 16.15% for C9. The microbial diversity and abundance in C9 and C1 were compared using high-throughput sequencing. The relationship between NH3 emission, operating parameters, and the related functional microbial communities was also investigated. Results revealed that Nitrosospira, Nitrosomonas, Nitrobacter, Pseudomonas, Methanosaeta, Rhodobacter, Paracoccus, and Sphingobacterium were negatively related to NH3 emission. According to the above results, the optimal values for different operating parameters for the in situ NH3 control during kitchen waste composting were, respectively, moisture content of 70%, C/N ratio of 35, and aeration rate of 15 L/min, with the order of effectiveness from high to low being aeration rate > C/N > moisture. This information could be used as a valuable reference for the in situ NH3 emission control during kitchen waste composting. 相似文献
15.
为进一步提高铁炭内电解法处理制药废水的处理效率,采用添加不同强化剂的方法考察分析强化因子的影响效果.在C加入量10g/L,铁屑30g/L,反应时间150 min,pH值7.5的条件下,以不同的盐、金属铜、双氧水作强化剂分别加入反应体系中,检测COD去除效果.实验结果表明:当每升废水中分别加入氯化铜、硫酸锰、硝酸镍、金属... 相似文献
16.
采用A/O工艺,在连续运行条件下,以DO、SRT和硝化液回流比(R)为影响因素,对A/O生物脱氮工艺处理模拟城市生活污水过程中N2O的释放进行了研究。实验结果表明,SRT对A/O工艺N2O释放的影响最大,其次是DO,R的影响最小。N2O转化率随着SRT的升高而降低,当SRT从10 d升高到20 d时,总N2O平均转化率从0.319%下降到0.002%。总N2O转化率随着好氧池DO的升高先降低后有所升高,当DO分别为0.6 mg O2/L、1.2 mg O2/L、2.5 mg O2/L时,反应器的总N2O平均转化率分别为0.306%、0.007%和0.013%。R对N2O释放的影响差异不明显,总N2O平均转化率在300%时最低,为0.007%。N2O释放量最低的工艺运行条件组合是SRT为20 d、DO为1.2 mg O2/L、R为300%。 相似文献
17.
The H 2O 2/UVC process was applied to the photodegradation of a commercial formulation of glyphosate in water. Two organisms ( Vibrio fischeri bacteria and Rhinella arenarum tadpoles) were used to investigate the toxicity of glyphosate in samples M 1, M 2, and M 3 following different photodegradation reaction times (120, 240 and 360 min, respectively) that had differing amounts of residual H 2O 2. Subsamples of M 1, M 2, and M 3 were then used to create samples M 1,E, M 2,E and M 3,E in which the H 2O 2 had been removed. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in tadpoles to determine possible sub-lethal effects. In V. fischeri, M 1,E, which was collected early in the photodegradation process, caused 52% inhibition, while M 3,E, which was collected at the end of the photodegradation process, caused only 17% inhibition. Survival of tadpoles was 100% in samples M 2, M 3, and in M 1,E, M 2,E and M 3,E. The lowest percentages of enzymatic inhibition were observed in samples without removal of H 2O 2: 13.96% (AChE) and 16% (BChE) for M 2, and 24.12% (AChE) and 13.83% (BChE) for M 3. These results show the efficiency of the H 2O 2/UVC process in reducing the toxicity of water or wastewater polluted by commercial formulations of glyphosate. According to the ecotoxicity assays, the conditions corresponding to M 2 (11 ± 1 mg a.e. L ?1 glyphosate and 11 ± 1 mg L ?1 H 2O 2) could be used as a final point for glyphosate treatment with the H 2O 2/UV process. 相似文献
18.
Pentachlorobenzene (PeCB) in simulated flue gas was destructed by a commercial V 2O 5-WO 3/TiO 2 catalyst in this study. The effects of reaction temperature, oxygen concentration, space velocity and some co-existing pollutants on PeCB conversion were investigated. Furthermore, a possible mechanism for the oxidation of PeCB over the vanadium oxide on the catalysts was proposed. Results show that the increase of gas hourly space velocity (GHSV) and the decrease of operating temperature both resulted in the decrease of PeCB removal over the catalyst, while the effect of the oxygen content in the range of 5-20% (v/v) on PeCB conversion was negligible. PeCB decomposition could be obviously affected by the denitration reactions under the conditions because of the positive effect of NO but negative effect of NH 3. The introduction of SO 2 caused the catalyst poisoning, probably due to the sulfur-containing species formed and deposited on the catalyst surface. The PeCB molecules were first adsorbed on the catalyst surface, and then oxidized into the non-aromatic acyclic intermediates, low chlorinated aromatics and maleic anhydride. 相似文献
19.
The sensitivity of in-cloud oxidation of SO 2 in corrective clouds to a number of chemical and physical parameters is examined. The parameterization of precipitation growth processes is based on the work of Scott (1978) and Hegg (1983). A chemical model predicts gas and aqueous phase distributions of soluble gases and in-cloud uncatalyzed oxidation of SO 2 by O 3 and H 2O 2. Sulfate aerosol and SO 2, CO 2, NH 3, H 2O 2 and O 3 gases and their aqueous phase dissociation products are treated.The results indicate that in-cloud conversion is an important removal mechanism for SO 2 and accounts for a significant fraction of the precipitation sulfate. However, except at low SO 2 concentrations, the precipitation sulfate concentration is insensitive to the initial SO 2 concentration; the sulfate concentration is most sensitive to the initial H 2O 2 and NH 3 concentrations. At low SO 2 concentrations, the precipitation sulfate concentration is determined primarily by the initial sulfate aerosol concentration. The feedback between sulfate production and pH is important in limiting SO 2 oxidation by O 3. If gas phase H 2O 2 of order 1 ppb is the major source of aqueous phase H 2O 2 for S(IV) oxidation, it is likely that the oxidation reaction is oxidant limited. The sulfate concentration is a decreasing function of the precipitation rate. At low rainfall rates (< 1 mm h −1), ice phase growth decreases the sulfate concentration. However, the results are insensitive to an ice phase origin at moderate and high rainfall rates. 相似文献
20.
The catalysts such as Fe, Bi 2O 3, and Fe-doped Bi 2O 3 were synthesized for the sonophotocatalytic treatment of synthetic dye and real textile wastewater. The resultant catalysts were characterized for its size and uniform shape using x-ray diffractogram (XRD) and scanning electron microscopy (SEM) which signified the nanorod shape formed Bi 2O 3. The higher ultraviolet light absorbance capacity of the catalysts was also evident using diffuse reflectance spectroscopy (DRS). Initially, the effect of conventional parameters such as initial pH, gas bubbling (argon, oxygen, air and nitrogen) and oxidant addition (H 2O 2 and peroxymonosulfate) in the presence of sonolysis (22 and 37 kHz frequency) and photolysis (UV-C light) on 10 ppm Basic Brown 1 dye was studied. The results showed that highest decolorization of 62 % was attained for 3 g/L peroxymonosulfate under 37 kHz frequency sonolysis treatment. Secondly, with the catalyst study, highest of 46 % dye color removal was obtained with 4 g/L Fe under 37 kHz frequency sonolysis treatment. The sonophotocatalytic treatment of dye with Fe-doped Bi 2O 3 catalyst in combination with peroxymonosulfate showed highest color removal of 99 %. Finally, the sonophotocatalytic treatment of real textile wastewater in the presence of 3 g/L Fe-doped Bi 2O 3 and 6 g/L peroxymonosulfate reduced the total organic carbon (TOC) and chemical oxygen demand (COD) level to 77 and 91 %, respectively, in 180 min. The reported treatment process was found to treat the synthetic dye and real textile wastewater effectively. 相似文献
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