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Y型分子筛负载铁催化剂对活性艳蓝KN-R脱色的研究 总被引:2,自引:0,他引:2
利用Y型分子筛负载铁催化剂对活性艳蓝KN-R的脱色进行研究,探讨了催化剂的制备方法、铁负载量、投加剂量、反应体系pH值以及焙烧温度对活性艳蓝KN-R催化脱色效率的影响,并考察了催化剂的重复利用性能.结果表明:离子交换法制得的Y型分子筛负载铁催化剂表现出较佳的染料脱色性能.在pH<3.0,H2O2投加剂量为50.0 mmol·l-1,催化剂投加剂量为4.0g·l-1的条件下,对初始浓度为250mg·l-1的KN-R模拟染料废水,30 min之内脱色率达95%以上.采用有机酸络合铁作为铁源制得的Y型分子筛负载铁催化剂的催化活性大幅增强,但催化剂稳定性降低.铁负载量影响染料的脱色反应活性,过量负载会导致染料脱色效率降低;同样,适度增大催化剂用量可促进染料脱色效率,但过量投加不利于染料的脱色.pH<3.0为该Y型分子筛负载铁催化剂的适用pH条件;催化剂重复利用三次后,1h内对活性艳蓝KN-R的脱色率仍可达95%以上. 相似文献
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从土壤中分离到一株活性艳红K-2BP脱色酵母菌株Y-63,根据其生理生化特征和26S rRNA基因序列相似性分析,鉴定为Pseudozyma rugulosa.该菌在16 h内对100 mg/L的活性艳红K-2BP脱色率为94%,其机理属于降解脱色.该染料脱色的最佳接种量(φ)应不低于5%,最适pH在4~9之间,(NH4)2SO4浓度(w)不低于0.1%,葡萄糖浓度(w)不低于0.2%.此外,该菌株对其它9种50 mg/L的染料(活性艳蓝X-BR、媒介漂蓝B、活性翠蓝KN-G、酸性媒介黄GG、媒介红S-80、依加仑蓝FBL 200%、弱酸艳红B、活性黑KN-B和活性红M-3BE)的脱色率在10%~96%之间.该研究表明酵母Y-63在染料废水的处理上具有较好的应用潜能. 相似文献
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利用中心组合设计和响应面分析方法对影响UV/TiO2光催化降解酸性玫瑰红B的主要因素(初始pH值、K2S2O8浓度、TiO2浓度)进行分析.其中初始pH值、K2S2O8浓度和TiO2浓度的高、低水平分别为4-5.6,26-36mg·l-1和0.53-1.87mg·l-1,分析参数为脱色率的变化.通过使用Design-Expert 5软件可得到1个2次响应曲面模型,最佳的初始pH值、K2S2O8浓度和TiO2浓度分别为4.69,29.73mg·l-1和1.18 mg·l-1,脱色率达到最大(94.21%). 相似文献
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UV-vis/草酸铁/Fenton体系降解蒽醌染料 总被引:2,自引:0,他引:2
以活性艳蓝KN—R作为研究对象,考察了处理活性艳蓝KN-R的主要影响因素。在固定染料浓度为100 mg/L时,得到氧化体系的最佳用量比值为ρ(Fe2+):ρ(H2O2):ρ(H2C2O4)为1:15:1.5。在最佳条件下,脱色率达到95%以上,COD和TOC去除率分别达到87.7%和66.8%。活性艳蓝KN-R脱色的动力学模型为拟一级反应模型。 相似文献
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间歇反应器内污泥衍生吸附剂去除水溶液中镉、镍离子 总被引:3,自引:0,他引:3
利用城市污水厂的污泥化学活化法热解产生的吸附剂 ,在间歇反应器内对水溶液中Cd2 和Ni2 离子进行吸附性能的研究 .考察了溶液的pH值、接触时间、吸附剂的投加量及吸附质初始浓度对吸附效果的影响 ,结果表明 ,Cd2 ,Ni2 离子吸附达到平衡时的接触时间为 60min,pH值为 5 5— 6 0 ,溶液的初始浓度为 40mg·l- 1 和 30mg·l- 1 ,吸附剂的投加量不少于 1 0g·l- 1 和 2 0g·l- 1 . 相似文献
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固定化无花果曲霉对活性艳蓝KN-R的脱色 总被引:4,自引:0,他引:4
采用海藻酸钙法固定不同状态无花果曲霉,形成活菌固定化小球和死菌固定化小球。同时考察了不同因素如培养时间、温度、pH、染料浓度对活性艳蓝KN-R的脱色影响。试验结果表明:在33℃、pH为5.0、150r/min的振荡条件下,经66h它对活性艳蓝KN-R的脱色达到最佳效果。两种不同状态固定化小球的脱色率有较大的差别,其中活菌固定化小球的脱色率明显高于死菌固定化小球。其中活菌固定化小球经3次脱色后能重复使用,脱色率仍达79.8%。 相似文献
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酵母菌株Pseudozyma rugulosa对合成染料脱色的初步研究 总被引:2,自引:0,他引:2
通过筛选实验,从土壤中分离出一株对活性艳红KBP具有明显脱色效果的酵母菌株,鉴定为Pseudozymarugulosa.采用含50mg·l-1活性艳红K2BP的液体培养基同步培养脱色,发现该菌株在9h时对活性艳红K2BP的脱色率为99%.此外,该菌株对另外九种染料的脱色率在22%—98%之间.其中,对偶氮染料——弱酸艳红B、活性黑KNB和活性红M3BE的脱色率都达到了96%以上,对三苯甲烷染料——酸性媒介漂蓝B的脱色率达到了89%. 相似文献
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以自制活性炭/聚四氟乙烯(PTFE)气体扩散电极在无隔膜体系发生H2O2进行电化学消毒的系统研究,探讨了膜电极中PTFE质量分数WPTFE对氧气电还原特性的影响,研究了膜电极中载铂量WPt和造孔剂含量WNH4HCO3、外部操作条件pH值、氧气流速、溶液含盐量和电流密度对杀菌效率的影响.结果表明,WPTFE对H2O2的产率有明显的影响:产H2O2的峰电流先是随着WPTFE的增加而增大,然后减小.当WPTFE=50%时,峰电流最高.杀菌效果随着载铂量的提高而改善,WPt增加到4‰,杀菌效果和WPt=3‰时的杀菌效果基本相当.适量造孔剂的添加有效地改善了杀菌效果.杀菌效率随着pH值的下降迅速提高;该体系pH值适用范围较广:当原水细菌总数为106cfu.ml-1,pH=3—10,以载铂量WPt=3‰的气体扩散电极作为阴极进行电解,30 min后杀菌效率均能达到80%以上.在一定范围内增加氧气流速对H2O2的产生及杀菌效率的变化无太大影响.一方面,高的氧气流速增大了水的电阻,增加了杀菌能耗,提高了气体扩散电极体系杀菌的运行成本;另一方面,高的氧气流速在一定程度上缩短了处理时间,降低了设备投资.含盐量的增加使杀菌能耗减小,因此本电化学杀菌体系更加适合于高含盐量的水.杀菌效率随电流的升高而增加,但电流较大时,杀菌效率增加幅度较小.电流密度控制在6.6 mA.cm-2较为适宜. 相似文献
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Xufang Wang Dongli Guo Jinna Zhang Yuan Yao Yanbiao Liu 《Frontiers of Environmental Science & Engineering》2023,17(9):106
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Algal turfs are the major primary producing component on many coral reefs and this production supports higher levels in the
complex reef trophic web. Rates of metabolism of algal turfs are related positively to water motion, consistent with limitation
by the diffusion of a substance through a boundary layer. Based on engineering mass transfer theory, we hypothesized that
photosynthesis of algal turfs is controlled by rates of mass transfer and responses of photosynthesis to increasing flow speed
should be predicted by engineering correlations. This hypothesis was tested in ten experiments where photosynthesis was estimated
in a flume/respirometer from changes in dissolved oxygen at eight flow speeds between 0.08 and 0.52 m/s. Flow in the flume
and over the reef at Kaneohe Bay, Oahu, Hawaii was estimated using hot-film thermistor and electromagnetic current meters.
Rates of photosynthesis were related positively to flow in all experiments and plots of the log of the average Sherwood number
(Sh
meas) versus log Reynolds number (Re
D) for each experiment are lower than predicted for mass transfer through a turbulent boundary layer. Algal turf-covered plates
are characterized as hydrodynamically transitional to fully rough surfaces and the lower than predicted slopes suggest that
roughness reduces rates of mass transfer. A negative correlation between algal turf biomass and slopes of the log Sh
meas−log Re
D plots suggests that mass transfer to algal turfs is affected significantly by the physical structure of the algal community.
Patterns of photosynthesis based on changes in dissolved oxygen and dissolved inorganic carbon concentrations (DIC) indicate
that the flow speed effect is not the result of increased flux of oxygen from the algal turfs, and combined with the short
response time to flow speed, suggest that DIC may limit rates of photosynthesis. Although there are differences between flow
in the flume and flow over algal turfs on the reef, these results suggest that photosynthesis is controlled, at least in part,
by mass transfer. The chemical engineering approach provides a framework to pose further testable hypotheses about how algal
canopy height, flow oscillation, turbulence, and substratum roughness may modulate rates of metabolism of coral reef algal
turfs. 相似文献
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在生活垃圾焚烧烟气模拟净化实验中,采用氯化镉作为气态重金属的发生源,模拟改性钙基吸附剂对重金属的动态吸附,并对重金属入口浓度、吸附温度、吸附剂投加量以及烟气组分等因素进行研究,结果表明:(1)反应温度对镉的去除有一定的影响,温度升高,去除率下降;(2)钙基吸附剂对Cd的去除率随着Cd入口浓度的增加而降低;(3)吸附剂投加量增加,去除率随之增加,但当加入量达到100g以上时,去除率不再变化;(4)HCl气体的存在能促进Cd的吸附,SO_2气体的存在则抑制Cd的吸附;(5)随着吸附质CdCl_2初始浓度的增加,钙基吸附剂的吸附量逐渐增加并趋向平衡,且与活性炭相当. 相似文献
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Lei Li Shijie Yuan Chen Cai Xiaohu Dai 《Frontiers of Environmental Science & Engineering》2022,16(6):74
Methanogenesis is the last step in anaerobic digestion, which is usually a rate-limiting step in the biological treatment of organic waste. The low methanogenesis efficiency (low methane production rate, low methane yield, low methane content) substantially limits the development of anaerobic digestion technology. Traditional pretreatment methods and bio-stimulation strategies have impacts on the entire anaerobic system and cannot directly enhance methanogenesis in a targeted manner, which was defined as “broad-acting” strategies in this perspective. Further, we discussed our opinion of methanogenesis process with insights from the electron transfer system of syntrophic partners and provided potential targeted enhancing strategy for high-efficiency electron transfer system. These “precise-acting” strategies are expected to achieve an efficient methanogenesis process and enhance the bio-energy recovery of organic waste. 相似文献
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Minghui Yang Seokjoon Kwon Yordan Kostov Avraham Rasooly Govind Rao Upal Ghosh 《Environmental Chemistry Letters》2011,9(2):235-241
Single-wall carbon nanotubes (CNT) are one of the most attractive engineered nanomaterials due to their unique electrical,
mechanical and thermal properties, and potential use in a variety of commercial products. Due to their small size, CNT could
become easily airborne and reach the various environmental compartments and eventually the food chain and humans. However,
the environmental fate processes and health impacts of CNT are not clear. This study investigated a method for the quantitative
measurement of carbon nanotube (CNT) in natural media such soil and benthic organism tissues. Fluorescence dye Nile blue was
used for noncovalent labeling of CNT to enable their fluorescence detection. Labeled nanotubes were successfully detected
in soil samples as well as in worm tissue. We were also able to detect the presence of labeled carbon nanotubes in worms exposed
for 1 week to CNT-laden soil, which indicates CNT may transfer through environmental food web. The method allows for laboratory
measurements of CNT mass transfer and partitioning into various environmental systems. 相似文献
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H.C.M.R. is a fluidised multiphasic reactor. In this reactor the rate of oxygen transfer was studied in order to characterise its efficiency as a system of aerobic treatment. The studied parameters are: The size of the reactor, the volume of the particles, the oxygen transfer rate. Several experiments were carried out with a variation of the above parameters and the results of the experiments are summarised as follows: The overall mass transfer rate coefficient k 1 a increases with increasing of upflow gas rate (Ug ); The overall mass transfer rate coefficient k 1 a decreases with increasing of the inert support volume (Vs); The overall mass transfer rate coefficient values from cylinder shaped particles were higher than those for disc shaped particles. 相似文献
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Yingbin Hu Ning Li Jin Jiang Yanbin Xu Xiaonan Luo Jie Cao 《Frontiers of Environmental Science & Engineering》2022,16(7):90
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利用碳还原剂和氯化钙熔盐药剂在1100℃下还原污泥焚烧灰中的磷酸盐为气态磷单质并去除,采用X射线衍射分析(XRD)残渣的组成和热重质谱(TGA-MS)分析反应过程.结果表明,添加氯化钙可显著提高污泥焚烧灰除磷效率,氯化钙的最优添加量为25%质量分数,此时污泥焚烧灰除磷效率为82%.XRD结果显示,污泥焚烧灰经熔盐处理后形成了氯磷灰石(chlorapatite),珍珠云母(margarite)等物质,其中氯磷灰石的形成有利于焚烧灰中磷的还原.对TGA-MS结果进行热解动力学反应拟合,结果显示,污泥焚烧灰除磷反应在添加少量氯化钙添加时为均相反应;污泥焚烧灰除磷反应在添加较多氯化钙时为固相扩散反应.固相反应的发生有利于降低磷酸盐还原反应温度并提高去除效率. 相似文献