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垃圾渗滤液经过常规的生化处理后难以达到国家的排放标准,高级氧化技术作为深度处理工艺之一日益成为处理的重要方法。目前,垃圾渗滤液深度处理的高级氧化技术主要有臭氧氧化法、电催化氧化法、光催化氧化法、Fenton氧化法、过硫酸盐氧化法、超声氧化法等几种方法。系统阐述了这些高级氧化法的机理以及国内外研究者们的研究成果,比较了各高级氧化技术的优缺点,并对这些技术的研究方向做了展望。最后,介绍了高级氧化技术之间的一些优化组合工艺在垃圾渗滤液深度处理中的研究成果,这些工艺互相协同,在技术和经济上是切实可行的,有望成为垃圾渗滤液深度处理技术工程化的发展方向之一。 相似文献
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《Ceramics International》2020,46(3):3091-3098
The effect of carbon content of MgO-C refractory was studied with respect to the physical properties, oxidation resistance and kinetics. The oxidation mechanism was investigated by calculating the relevant parameters of oxidation and analyzing the evolutions of phases and microstructures. The oxidation resistance of MgO-C refractory was influenced by the indirect oxidation of carbon through the formation of the MgO constituent layer. The effect of indirect oxidation resulted in the MgO-C refractory with 3 wt% carbon content having a lower oxidation rate and weight loss rate when fired at 1600 °C than when fired at 1400 °C. The oxidation kinetics results based on shrinking core model showed that the effective diffusion coefficient and full oxidation time increased with the increasing of carbon content. This seemingly paradoxical result was mainly due to the effect of the molar density of carbon prevailing over that of the effective diffusion coefficient in the oxidation process. 相似文献
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综述了近年来受到广泛关注和应用的高级氧化技术,包括Fenton法、光催化氧化法、O3联合氧化法、湿式氧化法、电化学氧化法以及超临界水氧化法等。介绍了这几种高级氧化技术的原理、特点以及在废水处理领域中的应用进展。 相似文献
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高级氧化技术是近年来备受人们关注的印染废水处理技术,本文分析了印染废水的基本特征,并就高级氧化技术中的超临界水氧化技术、湿式氧化技术、臭氧氧化技术、电化学氧化技术、Fenton氧化技术、超声波处理技术和光催化氧化技术在印染废水中的应用做了阐述,介绍了各技术的基本原理和应用中优缺点,为高级氧化技术在处理印染废水的实际应用提供了理论依据。 相似文献
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简要介绍了几种典型的高级氧化技术包括Fenton试剂氧化法、O3氧化法、光催化氧化法、电催化氧化法和湿式氧化法,阐述了它们处理难降解有机废水的反应机理、特点、存在的主要问题及其应用进展,同时展望了各种高级氧化法的发展前景。 相似文献
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Kinetics of Thermal, Passive Oxidation of Nicalon Fibers 总被引:1,自引:0,他引:1
Yuntian T. Zhu Seth T. Taylor Michael G. Stout Darryl P. Butt Terry C. Lowe 《Journal of the American Ceramic Society》1998,81(3):655-660
The oxidation of Nicalon fibers is a concern, because of its potential as a reinforcement of high-temperature composites, whose service conditions involve high-temperature, oxidizing environments. Two limiting types of oxidation mechanisms are often used to describe the kinetics: chemical-reaction-controlled oxidation, at small oxide thicknesses, and diffusion-controlled oxidation, at large oxide thicknesses. Neither mechanism can satisfactorily describe the intermediate region where the oxidation kinetics are controlled jointly by both the chemical reaction rate at the interface and the diffusion of oxygen through the oxide layer. To describe the entire oxidation process with a general relationship, one must consider all stages of the oxidation process, namely (i) adsorption of oxygen at the outer surface of the oxide, (ii) diffusion of oxygen from the outer surface toward the interface where oxidation occurs, and (iii) reaction at the interface to form a new layer of oxide. Previously, a very useful general relationship was derived for the oxidation kinetics for a flat plate, which could account for all three stages of oxidation. However, that equation is inadequate to describe the oxidation of cylindrical fibers, because the effective area for oxygen diffusion changes along the diffusion path and the oxidation interfacial area decreases as the oxide thickness increases for cylindrical fibers. In this paper, we have derived a general kinetic relationship for the oxidation of cylindrical fibers, which can account for all stages of oxidation. Comparison of the theory with experimental data of Nicalon fibers shows good agreement. 相似文献
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对环己烷仿生催化氧化产物与无催化氧化产物进行了分析,对氧化液中各组分的比例和烷四釜中各杂质的含量进行了对比。结果表明:与环己烷无催化氧化相比,仿生催化氧化环己烷转化率高,产物中醇、酮、酸、酯含量高,过氧化物含量降低;烷四釜中杂质种类相同,各组分的含量不同,其杂质总量约为无催化氧化的1.5倍,杂质可在精馏过程中分离。 相似文献
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综述了天然气部分氧化制合成气的研究进展,包括天然气无催化部分氧化、固定床催化部分氧化、两段转化法、膜反应器新工艺、流化床反应工艺、氧化剂研究、微波辐射加热部分氧化、部分氧化的机理,以及部分氧化工艺的催化剂研究。 相似文献
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《Ceramics International》2015,41(6):7929-7936
Oxidation of carbon is one of the main problems in alumina–carbon based refractory. In this paper, the oxidation behaviors of novel carbon composite brick and traditional carbon brick were investigated by non-isothermal and isothermal experiments, and the samples after oxidation were examined by SEM and EDS analysis. The results show that the oxidation resistance of carbon composite brick is better than that of carbon brick. At 800−1200 °C, the oxidation kinetics of carbon brick follows the linear rate law, which belongs to non-protective oxidation, and the oxidation activation is 5586.76 J/mol. However, the oxidation kinetics of carbon composite brick follows the parabolic rate law, which belongs to protective oxidation. The compressive strength decreases with the increasing mass loss after oxidation due to the carbon loss, so for carbon composite brick which has less content of carbon the oxidation resistance is better than that of carbon brick. Furthermore, the existence of SiC in the surface of carbon composite brick is another reason for its good oxidation resistance. 相似文献
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介绍了高级氧化技术的特点和适用范围;分别阐述了化学氧化技术、电化学氧化技术、湿式氧化法、超临界水氧化技术等主要高级氧化技术的基本原理、研究进展及应用前景;例举了高级氧化技术的应用实例。结果表明,高级氧化技术适用于流量小、浊度高、降解难的有机废水处理,具有效果稳定的优点。 相似文献
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高级氧化技术处理染料废水的研究进展 总被引:20,自引:2,他引:20
由于染料废水中含有高浓度难降解有机污染物,对其有效处理一直是个难题.综述了近几年国内外采用湿式氧化法、Fenton法、光化学与光催化氧化法、电化学法、臭氧氧化法、微波辅助氧化法和超声氧化法等高级氧化技术处理染料废水的进展情况,并指出了高级氧化技术在染料废水处理中的发展趋势. 相似文献
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葡萄糖酸合成方法研究进展 总被引:2,自引:0,他引:2
介绍了葡萄糖氧化制备葡萄糖酸的各种氧化方法及进展,并讨论其原理及优缺点,主要讨论了工业上广泛使用的生物发酵法和近年来发展比较快的多相催化氧化法,重点介绍了催化氧化法制葡萄糖酸的催化剂失活和制备的研究情况. 相似文献
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通过半连续实验考察了对二甲苯(PX)二次氧化过程中的液相氧化,并对该过程进行了模拟计算。设计和进行了包含PX液相氧化、中断反应以及降温二次液相氧化三个阶段的实验;通过动力学实验测定和数据回归确定了基于芳烃氧化自由基链式反应机理的PX液相氧化动力学模型的参数;采用建立的PX液相氧化机理模型对PX分段氧化过程进行了预测。结果表明,对中断反应后的降温二次液相氧化间歇过程,采用第一阶段末期自由基浓度做初值时模型预测值与实验值符合良好;而假设自由基初值浓度为零时,PX液相氧化动力学模型对二次氧化的液相反应预测效果较差,其原因可能是中断降温后的氧化母液中存在过氧基团会使二次液相氧化反应极快地被再引发启动。 相似文献