碳黑的表面臭氧氧化

研究了碳黑表面的臭氧氧化。研究表明,碳黑的表面含氧量与提供给单位碳黑表面的臭氧量成正比。臭氧氧化增加了碳黑的表面酸性。红外光谱及Ｘ光电子能谱表明,臭氧氧化在碳黑表面引进了羧基基团。氧化后的碳黑进一步加强了硝基丁二烯橡胶的物理性能。     

层燃炉煤燃烧碳黑形成规律的实验研究

设计了可移动式-固定床块煤燃烧实验台,进行了层燃炉块煤燃烧碳黑生成规律的研究。结果表明,随着温度的升高,碳黑和焦油的生成量先增加后减少,呈马鞍形,这是碳黑、焦油形成过程与氧化过程相互竞争的结果,高温有利于减少碳黑的排放;随着气体停留时间的延长,碳黑和焦油的生成量减少;高挥发分煤不完全燃烧时,碳黑的生成量较高;随着氧量比的增大,碳黑和焦油的生成量逐渐减少;当氧量为理论燃烧煤所需氧量的0.9倍时,没有碳黑和焦油生成。     

碳载体处理对Pd催化氧化甲酸的影响

采用饱和Co盐浸渍碳黑,然后高温热处理.发现处理后的碳黑微孔体积减少,介孔体积增加,更适于作为催化剂的载体.用处理后的碳黑制备的碳载Pd催化剂比未处理的碳黑做载体制备的催化剂对甲酸氧化具有更高的电催化活性.XRD结果可以看出,经Co盐浸渍处理过的碳黑中含有一定量的Co,有助于金属Pd在碳黑表面的分散,增加活性金属的电化...     

专利信息

改进的转化碳黑及其制备方法公开号 :12 32 84 2　　申请人 :德古萨—于尔斯股份公司公开了一种转化碳黑及其制备方法。该转化碳黑具有更小的滚动阻力以及同样的或改善了的湿滑性能。其粒度分布中大直径的颗粒所占的比例较小。用这种碳黑制备的橡胶组合物就会具有一种改善了的磨损效应。通过控制燃烧室中的燃烧 ,使碳黑核形成 ,并使碳黑核立即与碳黑原料接触 ,这样就可以在传统的碳黑反应器中来制备转化碳黑。如果通过合适的方式增加燃烧空气和碳黑原料的加入量 ,则可以使所形成的碳黑中较大的颗粒所占的比例较小。 (发明人 :康尼·福格勒 ;…     

碳黑用量对橡胶减振器性能的影响

本文研究碳黑用量对橡胶减振器性能的影响规律。结果表明,随着碳黑用量的增加,胶料拉伸和撕裂强度都呈先上升后下降的趋势;减振器的静刚度、动刚度和硬度呈现上升趋势,而损耗因子呈现下降趋势,振动传递率呈现上升趋势,且在碳黑用量为20份时,振动传递率最小,减振器减振性能最好;并建立了碳黑用量-硬度、碳黑用量-静刚度、碳黑用量-动刚度的数学模型     

控制碳黑反应炉温的新方法

据美国专利3993447报导,美国菲利蒲石油公司通过控制加入碳黑反应炉燃烧室的燃料及空气的速度,用电子计算机来控制碳黑高温反应炉的炉温。占碳黑总产量90％以上的油炉法碳黑,通常是借助液态烃在特制的碳黑反应炉内热裂解制造的。烃热裂解所需的热量,一般是     

分散剂及碳黑对黑度的影响

采用不同的分散剂研磨分散进口高色素碳黑及国产高色素碳黑,结果显示分散剂对碳黑的黑度、黏度有非常明显的影响。合适的分散剂可以得到低黏度、低触变性、高黑度及偏蓝色色相的碳黑浆。     

碳黑在橡胶加工中的作用简析

碳黑在橡胶加工中扮演了非常重要的角色,作为橡胶补强体系中的重要成员,随着加工行业的不断发展,碳黑的加工工艺也在不断变化,全文主要对碳黑分别从分类、对橡胶加工的影响、工艺性能等几个方便对碳黑进行了阐述,为在橡胶加工过程中碳黑的使用提供了参考依据。     

碳黑洗涤水pH值测量系统的改造

以渣油为原料生产合成氨，在油气化过程中会产生大量的碳黑，再用水洗涤原料气中的碳黑，洗涤后的碳黑水呈酸性，必须加碱性水中和以防工艺管道的腐蚀。由于碳黑冷凝水温度高达121℃，压力0．1MPa，其中还带有油、碳黑渣及其它悬浮物，对碳黑洗涤水     

Shell碳黑回收操作方法改进之对比

1　工艺原理及流程简介Shell碳黑回收是 Shell气化工艺的配套装置 ,气化反应在生成原料气的同时生成 380 kg/h的碳黑 ,约占渣油总量 1 % (质量百分比 )。为了降低环境污染、减少原料消耗 ,此部分碳黑需经碳黑回收装置回收送气化利用。1 .1　工艺原理Shell气化反应生成的碳黑具有较强的亲水性 ,原料气经水洗涤后形成浓度为 0 .74% (设计值 )的碳浆 ,由于碳黑的亲油性大于亲水性 ,碳浆与适量石脑油混合后萃取形成 Φ1～ 3mm的碳黑球。碳黑球经分离后混入渣油中送回气化炉作为原料 ,以达到回收利用。1 .2　流程简介Shell碳黑回收装置分为三个…     

生物质碳烟颗粒物生成机理研究进展

介绍了生物质燃烧过程中碳烟颗粒物的生成机理,主要包括生物质碳烟的各种生成路径,生物质碳烟生成的中间产物多环芳烃,以及中间产物多环芳烃生成碳烟,多环芳烃、反应气氛、反应压力及反应温度等对碳烟颗粒物生成的影响,生物质金属离子对碳烟生成及碳烟的成长过程等影响。总结了现有生物质碳烟生成机理研究的不足,并对碳烟中间产物,碳烟一次、二次生成机理以及影响碳烟生成量的各种因素等进行系统研究;采用量子化学理论、矩方法以及激光检测试验等方法来研究生物质碳烟的生成机理,并可借鉴燃煤碳烟生成机理及柴油碳烟生成机理的研究方法及试验等;从生物质碳烟生成的热力学及动力学机制、成核演变理论、影响机制及试验方面等,并从化学反应和工程热物理的角度,深入研究生物质燃烧过程中碳烟颗粒物的生成机理与碳烟核成长演变行为,得到合理的生物质碳烟生成机理,为控制并减少雾霾环境影响的实际工程应用提供理论与实践指导。     

Single particle MS,SNMS, SIMS,XPS, and FTIR spectroscopic analysis of soot particles during the AIDA campaign

Within the framework of the AIDA soot aerosol campaign diesel soot particles, spark generated soot particles, and aerosol mixtures were characterized with respect to their chemical state using different surface sensitive analysis methods. A comparison between diesel soot and graphite spark generated soot revealed a significant difference in the chemical composition of the particle surfaces. No distinct change from external to internal mixing could be detected by single particle mass spectrometry for mixtures of diesel soot and (NH₄)₂SO₄ aerosol since the spectra of diesel soot and (NH₄)₂SO₄ aerosol were surprisingly similar due to sulfate on the surface of diesel soot particles and traces of carbon impurities on ammonium sulfate particles. In addition to the expected formation of new particles a considerable change of the soot particle surface was detected while exposing diesel soot or spark generated soot to α-pinene and ozone, indicating a surface layer formed by oxidation products of α-pinene. However, the oxygen-containing hydrocarbon fragments detected by single particle mass spectrometry were distinctly different for the two soot types, which can be explained by either the different product adsorption or ionization behavior. Depositions of α-pinene reaction products on the surface could be confirmed by QMS-SIMS and XPS for particles of both types of soot. Due to the high mass resolution of TOF-SIMS acidic derivatives were identified as reaction products of α-pinene and ozone. The analytical methods applied in this work elucidated the different properties of spark generated soot compared to diesel soot. Therefore, spark generated soot should only be used with care as a general diesel soot surrogate.     

Porosity changes in soot resulting from oxygen atom adsorption at 298 K

Previously reported experiments from our laboratory showed that soot oxidation by oxygen atoms at 298 K was dominated by large net oxygen atom adsorption on this soot. The adsorbed oxygen was stable at 298 K; at elevated temperatures, this oxygen desorbed entirely as carbon monoxide and carbon dioxide. Here, we describe experiments using electron microscopy and nitrogen adsorption measurements to characterize the as-collected soot, soot loaded with varying amounts of adsorbed oxygen, and this oxygen-loaded soot that has been thermally degassed. The electron micrographs show small changes in the soot except at very long oxygen-atom exposure times, for which significant carbon gasification has occurred. The nitrogen adsorption measurements show large increases in the micropore structure of soot on thermal desorption of the adsorbed oxygen. These results confirm our earlier conclusion that oxygen atom adsorption occurs throughout the soot particles, not just on the surface. These data further show that thermal desorption (of CO and CO₂) occurs from within the soot particles and does not result from migration of the chemisorbed oxygen to the soot surface.     

生物质热解碳烟的研究进展

碳烟是燃料不完全燃烧或气化形成的纳米级碳质颗粒,是空气中细颗粒物PM_2.5的主要来源之一,也是仅次于CO₂的温室效应主要贡献源之一。碳烟的生成会降低生物质热转化过程中的能量利用效率以及气化过程中合成气的品质。作为生物质热化学转化过程的初始步骤,热解碳烟的生成特性、形成机理和减排方法对转化过程中碳烟的控制具有指导意义。本文从生物质热解碳烟的取样、排放特性、理化性质、生成机理及减排措施等方面进行了综述。着重介绍了热解碳烟的产率、化学组成、微观样貌、内部结构和反应性等,总结了原料特性及热解工况对碳烟产率和反应性的影响,汇总了当前调控热解碳烟排放的主要措施。指出目前针对生物质热解碳烟前体的形成及演化转变机理仍不明确,热解碳烟的氧化反应机理研究鲜有报道。此外,热解碳烟生成受原料类型和热解工况等诸多因素影响,当前研究多为单因素的影响分析,缺乏针对碳烟排放的多因素耦合优化研究。     

Realistic contact for soot with an oxidation catalyst for laboratory studies

Laboratory temperature programmed oxidation (TPO) is popular for diesel soot oxidation catalyst screening. The method of depositing soot on the catalyst can be critical for the measured catalyst performance. Different methods for bringing the soot in physical contact with the catalyst were evaluated in order to determine which methods give a realistic contact. Suitable methods are filtration from a (artificial) soot aerosol, shaking in a sample bottle, mixing with a spatula, and dipping in a soot dispersion. For these preparation methods Printex U synthetic soot is a suitable model compound.     

Sooting and non-sooting propylene diffusion flames with irradiation of laser light

The structural change in co-flow propylene diffusion flames by irradiation of laser light is experimentally investigated to examine the effect of soot radiation at a certain position. The soot volume fraction and the flame/soot temperatures are measured by laser extinction and two-color-ratio pyrometry techniques. Transitions from a non-sooting to a sooting flame and vice versa are observed to depend on the irradiated positions of laser light. The structural change could be attributed to the following processes. When laser light is irradiated at the soot-formation region (lower part in the flame), the temperature of soot particles is increased by absorption of laser energy; the raised temperature enhances soot formation and increases the local volume fraction of soot. The increased amount of soot enhances the radiation loss and eventually lowers the flame temperature at the downstream direction. As a result, the soot-oxidation process is suppressed, and finally a non-sooting flame transforms to a sooting flame. The laser light irradiated at the competing section of soot formation and oxidation or at the oxidation section (upper part of the flame) also increases the temperature of soot particles, however, the increased soot temperature mostly enhances soot oxidation in these regions. Therefore, a decreased amount of soot lowers the radiation loss from the flame and maintains the flame temperature relatively high, compared with that without irradiation of laser light. As a result, the soot-oxidation process is more enhanced, and finally the transition from a sooting flame to a non-sooting flame occurs. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 6, pp. 74–81, November–December, 2006.     

炭黑纳米流体对火管式废热锅炉传热的影响

沥青气化生产合成气过程中有大量炭黑颗粒生成,炭黑颗粒对流体的流动和传热有较大影响。文章将含有炭黑纳米粒子的合成气定义为炭黑纳米流体,建立了炭黑纳米流体的单相流体模型,并用数值模拟的方法,分析了合成气中炭黑颗粒在传热中的作用。结果表明:炭黑粒子的直径、粒子流量对传热有很大影响。适当增加炭黑粒子的流量,可以增进传热,降低流动阻力。而炭黑粒子对火管废锅的产汽量影响很小。     

气相温度脉动对碳黑生成反应的影响(英文)

The effects of gas temperature fluctuations on soot formation and oxidation reactions are investigated numerically in a reacting flow. The instantaneous variations of soot mass fraction with time are obtained under the time-averaged gas temperature of 1500-1700 K. The simulation results show that the gas temperature fluctuation has obvious influence on the instantaneous processes of soot formation and oxidation. Within the present range of gas temperature, the gas temperature fluctuation results in generally lower soot mass fraction comparing to that without gas temperature fluctuation. The increase in the fluctuation amplitude of gas temperature leads to decrease in time-averaged soot mass fraction and increase in time-averaged soot particle number density.     

The role of fuel chemistry in dictating nanostructure evolution of soot toward source identification

Abstract

Laser derivatization is proposed as a diagnostic technique toward identifying the sources contributing to combustion produced soot. Fuel chemistry and the resultant oxygen content in nascent soot have been shown to influence the evolution of soot nanostructure upon laser derivatization. This is illustrated using the spectroscopic and microscopic characterization of biodiesel soot, with a systematic variation in fuel chemistry used to generate the soot. Functionalized carbon black is used as the control to independently verify the influence of material chemistry on nanostructure upon laser heat treatment. Results track with those observed for biodiesel soot. Reciprocally, the similarity in soot nanostructure observed after laser heating is tied to the likeness in fuel chemistry of biomass-fueled sources. Understanding the origin of differences or similarities in soot nanostructure upon laser heat treatment can help differentiate sources based on their contribution, thereby aiding in effective air quality control.

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