共查询到18条相似文献,搜索用时 234 毫秒
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微波-Fenton法处理垃圾渗滤液的研究 总被引:1,自引:1,他引:1
微波法用于消除有机污染物,具有快速、高效、不污染环境的特点。实验采用微波促进Fenton法降解垃圾渗滤液中的有机污染物,研究了Fenton试剂用量、微波功率、微波作用时间和pH值等对化学需氧量(COD)去除率的影响。实验结果表明,微波Fenton法处理垃圾渗滤液能提高反应效率,有效降低垃圾渗滤液中的COD浓度。微波-Fenton法处理20 mL的COD浓度为896 mg/L的垃圾渗滤液的优化条件为:调节pH值小于3,加入6 mmol/L的硫酸亚铁溶液6 mL,加入1 mL的H2O2,在微波功率800 W下加热处理4 min,其出水COD浓度可降至200 mg/L。 相似文献
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Fenton和类Fenton试剂广泛用于持久性有机污染物的矿化处理。微波辐射能提高Fenton和类Fen-ton法处理难降解有机废水的效率和处理能力。实验采用粉煤灰吸附分离与微波高级氧化的组合工艺处理垃圾渗滤液,以降低垃圾渗滤液的化学需氧量(COD)浓度。粉煤灰作为有机废水的吸附剂,同时粉煤灰中溶出的铁及其他过渡金属离子能与H2O2形成Fenton类试剂,产生氧化能力极强的羟基自由基(.OH),氧化处理其中的有机物。当粉煤灰量为20 g/L,pH=2,搅拌1 h后过滤分离;每1 L滤液加入2 mL 30%(质量比)的H2O2,入微波炉,设定温度80℃,功率600 W,在微波中作用20 min时,COD的去除率可达69.81%。 相似文献
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重金属与难降解有机污染物形成复合污染物,一些重金属离子也能催化H2O2产生.OH。利用微波加热的热效应和非热效应,以甲基橙溶液为模拟偶氮染料废水,研究了微波功率、微波辐射时间、pH值、Cr(III)和H2O2浓度等因素对甲基橙脱色率的影响。研究表明,Cr(III)能与H2O2形成类Fenton试剂,产生.OH,在微波的促进作用下,矿化有机物的原理。1 000 mg.L-1的甲基橙溶液,在H2O2浓度为12.0 mmol.L-1、5 mmol.L-1Cr3 溶液、pH=3、微波功率700 W下加热5 min,甲基橙脱色率达93%。 相似文献
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本文通过控制调节TiO2的用量探究光催化降解乐果适宜工艺的条件。研究表明,对于TiO2光催化降解乐果而言,在TiO2的用量为4.0g/L,反应物的起始浓度为0.05mol/L,pH值11,光照强度为250W时,乐果的降解率达到37.5%。 相似文献
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重金属与难降解有机污染物形成复合污染物,一些重金属离子也能催化H2O2产生·OH。利用微波加热的热效应和非热效应,以甲基橙溶液为模拟偶氮染料废水,研究了微波功率、微波辐射时间、pH值、Cr(Ⅲ)和H2O2浓度等因素对甲基橙脱色率的影响。研究表明,Cr(Ⅲ)能与H2O2形成类Fenton试剂,产生·OH,在微波的促进作用下,矿化有机物的原理。1 000 mg.L^-1的甲基橙溶液,在H2O2浓度为12.0 mmol.L^-1、5 mmol.L^-1Cr^3+溶液、pH=3、微波功率700 W下加热5 min,甲基橙脱色率达93%。 相似文献
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微波诱导铬渣催化氧化降解甲基橙溶液的研究 总被引:11,自引:5,他引:6
采用微波-铬渣法、微波-铬渣-H2O2法处理甲基橙溶液。研究了铬渣用量、溶液初始pH值、微波辐照时间、处理后放置时间等因素对溶液TOC去除率的影响。研究表明,对于150 mL的TOC浓度为200 mg/L的甲基橙溶液,铬渣用量为1 g,H2O2(30%)用量为1 mL,溶液初始pH值在4~10范围内,微波功率80 W,微波辐照3 min,TOC去除率可达80%,处理后放置足够长时间,色度去除率可达100%。处理后溶液中残留Cr(Ⅵ)浓度小于0.05 mg/L。 相似文献
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为了研究激光技术在废水降解领域中的应用,采用激光诱导空化技术对酸性黑溶液进行降解,通过紫外分光光度计对降解后的溶液进行分析表征,获得激光能量和溶液初始质量浓度对降解能力的影响;结合空泡动力学理论和空化化学效应,揭示了激光空化降解酸性黑溶液的机理。结果表明,随着激光能量的增加,初始质量浓度为20 mg/L的酸性黑溶液的降解率从0.78%逐步增加到27.28%;在100 mJ激光能量下,当溶液中酸性黑溶液的初始质量浓度从5 mg/L提升至20 mg/L时,降解率从98.55%降低至7.63%;激光能量越高,降解率越大;初始质量浓度过大,则激光空化难以对酸性黑溶液进行降解。该研究推进了激光空化降解染料等有机废水技术的发展。 相似文献
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研究了微波辐射冰醋酸和过氧化氢氧化法联合脱除原煤中有机硫的技术。采用单因子法考察了微波照射时间、微波照射功率、煤的粒度、煤与氧化剂的配比、冰醋酸与过氧化氢配制比等因素对脱硫率的影响 ,优选出了微波氧化联合法脱除原煤中有机硫的最佳工艺条件为 :微波功率为 85 0W ,照射时间为 2 0min ,煤与氧化剂的配比为 3g :5 0mL ,煤的粒度为d≤ 0 .2 3mm ,冰醋酸与过氧化氢的体积比为 1:1(摩尔比为 11.5 :38.5 ) ,脱硫率可达到6 0 .2 %。结果表明微波辐射下冰醋酸与过氧化氢氧化法是脱除原煤中有机硫的一种有效方法。 相似文献
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利用光谱技术研究等离子体的有关特性,已被许多科技工作者采纳.而发射光谱技术,具有设备简单、无污染、易于控制等优点,特别是当人们只关心等离子体参数的相对值及其随放电条件的变化规律时,更容易被采用.本文利用发射光谱法对双共振腔、大真空室微波等离子体源的特性进行了测量,得到了在不同的工作气压、不同的输入微波功率、室中不同位置的等离子体的发射光谱的规律.实验记录了不同条件下,在400~800urn波段,Ar原子谱和Ar 离子谱,结果表明;1)反应室中心处,压强一定,微波功率在400~900W之间变化时,不论是离子线还是原子… 相似文献
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微波促进H2O2脱色甲基橙溶液的研究 总被引:8,自引:3,他引:5
甲基橙是典型的偶氮染料之一。以甲基橙溶液模拟偶氮染料废水,探讨了在微波作用下,低浓度的甲基橙浓度、过氧化氢用量、溶液pH值、作用时问等因素对脱色率的影响。实验结果表明,微波能大大加快脱色反应速度,并能消除湿法氧化法可能产生的二次污染。微波功率为480W的条件下,酸性甲基橙溶液加入5%的H2O2作用5min,其脱色率可达到99.0%。对比甲基橙溶液处理前后紫外光谱的变化,说明经微波促进H2O2氧化后,甲基橙分子结构中的偶氮键发生断裂,破坏了偶氮-苯环共轭发色体系,从而达到了脱色的目的。 相似文献
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R Henda A Hermas R Gedye M R Islam 《The Journal of microwave power and electromagnetic energy》2005,40(1):7-16
A study describing the effect of microwave radiation, at a frequency of 2450 MHz, on the processes of communication and flotation of a complex sulphide nickel-copper ore is presented. Ore communication has been investigated under standard radiation-free conditions and after ore treatment in a radiated environment as a function of ore size, exposure time to radiation, and microwave power. The findings show that communication is tremendously improved by microwave radiation with values of the relative work index as low as 23% at a microwave power of 1.406 kW and after 10 s of exposure time. Communication is affected by exposure time and microwave power in a nontrivial manner. In terms of ore floatability, the experimental tests have been carried out on a sample of 75 microm in size under different exposure times. The results show that both ore concentrate recoveries and grades of nickel and copper are significantly enhanced after microwave treatment of the ore with relative increases in recovered concentrate, grade of nickel, and grade of copper of 26 wt%, 15 wt%, and 27%, respectively, at a microwave power of 1330 kW and after 30 s of exposure time. 相似文献
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Michele N Berteli Antonio Júnior Marsaioli Elisabeth Rodier 《The Journal of microwave power and electromagnetic energy》2007,40(4):241-250
Drying processes have evolved considerably over the years, aiming at the best conditions to shorten the processing time, but maintaining the highest final product quality. The application of vacuums to the microwave drying process might be interesting, especially for thermally sensitive products because the reduced boiling point of the solvent allows a lower temperature processing. The objective of the present work is to study and evaluate the process of drying a granulated product that is the basis of the drug hydrochlorthiazide, with an initial moisture content of 21% in dry basis. This study monitored the drying kinetics, product temperature and power absorbed by the sample using a bench scale vacuum microwave dryer. The equipment consisted of a cylindrical pressure vessel crossed by a wave guide, setting up a system whereby the vacuum pressure, the sample weight and the incident, reflected and residual microwave powers could be measured and evaluated, throughout the entire process. The experimental runs were established with an approximate incident microwave power at 20 W for absolute pressure levels of 50 and 75 mbar, working with samples of about 1.4 g. It was observed that the vacuum microwave process kinetics at both pressure levels showed little difference. The processes were carried out almost entirely in a regime of water evaporation, the product's temperature remaining below the solvent boiling temperature. The drying times were similar for both processes, whereas the absorbed power was slightly higher at the pressure of 75 mbar. 相似文献
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微波处理菘蓝种子的子叶发育与生物光子辐射的相关性 总被引:2,自引:0,他引:2
比较研究不同时间长度的微波辐照菘蓝种子对种子萌发率、淀粉酶活性、转氨酶活性、蛋白酶活性、蛋白质含量、游离氨基酸含量、总DNA含量、子叶发育状况及其生物光子辐射强度的影响.采用微波辐射浸泡3h的菘蓝(Isatis ind igotica Fort)种子.与对照相比,四种处理均能不同程度提高菘蓝种子萌发率、淀粉酶活性、转氨酶活性、蛋白酶活性,促进蛋白质、游离氨基酸、DNA合成,促进子叶发育,提高了生物光子辐射强度.低剂量微波辐射能提高种子生理生化代谢机能,促进种子萌发和幼苗生长发育,研究发现8 s微波预处理效果最为显著. 相似文献
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《Microwave Theory and Techniques》1961,9(4):312-314
The dependence of available excess noise in type microwave crystal-diode rectifiers on applied microwave power was measured. This may be approximated by a power law with stants characteristic of the particular crystal. As a consequence of the dependence of both excess noise and dc rectified power on power level, there is a level which minimizes the ratio of these tities. Similarly, in the case of a modulated microwave carrier there is an input level which minimizes the ratio of excess noise to power, and so provides optimum detection of small modulation. 相似文献