Integrated Study of Nanopowder Synthesis and Pollutant Control using Electrically-Assisted Combustion

电辅助燃烧纳米粉体合成与污染物控制综合研究

• 批准号: 0325057
• 负责人: Stephen Tse
• 金额: $ 32.25万
• 依托单位: Rutgers University New Brunswick
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-09-01 至 2007-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0325057&HistoricalAwards=false
• 关键词: Integrated; Study; Nanopowder; Synthesis; Pollutant

The objective of this work is fundamental understanding of the mechanisms of particle formation, growth, and aggregation in combustion systems subjected to external electric fields and utilization of that understanding to define process conditions that enable both high-rate deposition of non-agglomerated nanopowders and control of pollutant particulate emissions. The ceramic nanopowders investigated Initially are silica (SiO2), titania (TiO2), alumina (Al2O3) and zirconia (ZrO2) using highly volatile precursors. The pollutant particulates investigated are soot and particulates containing toxic metals such as lead (Pb) and chromium (Cr). The consolidated research program deals with the effects of applying electric fields on formation of solid particles in flames and addresses concurrently issues in both materials synthesis and environmental engineering. Experiments are conducted in aerodynamically simple flow fields, i.e. flat-flame stagnation-point (premixed) and flat-flame counterflow (non-premixed), to characterize the effects of electric field and of other controllable process parameters (including pressure) on chemical composition, primary particle size, crystallinity, and degree of agglomeration. The use of multiple precursors to produce doped, coated, or mixed nanocyrstalline nanoparticlesis investigated. The characteristics of film deposition in an electric field are examined with respect to composition, morphology, deposition patterns, and sintering. Advanced laser diagnostics, electron microscopy, and X-ray diffraction are utilized to model and analyze the effects of flame structure (due to process inputs) on particle evolution. A computational model incorporating detailed gas-phase chemical kinetics and transport (including electric field effects) is developed along with models for particle formation, growth, and aggregation. Broader impact Among the processes that have been demonstrated for flame synthesis of nanopowders, the approach of applying electric fields is one of the most promising in terms of precise control of primary particle size, crystallinity, and aggregate size. The same methodology can be used for the control of particulate emissions from combustion systems used for power generation and incineration. The research and experimental facility are incorporated into the new curriculum onnanomaterials science and engineering being offered as a joint program between several departments and into the graduate curriculum on advanced experimental methods. The involvement of underrepresented minorities and women in engineering is increased by supporting undergraduate research as part of the Douglass Project for Rutgers Women in Math,Science, and Engineering. The training of students (at high school, undergraduate, and graduate levels) for the high-technology workforce is promoted by partnering with industry, state, and the Center for Nanomaterials Research..

这项工作的目的是从根本上了解受外电场作用的燃烧系统中颗粒的形成、生长和聚集的机制，并利用这种理解来定义能够高速沉积非团聚纳米粉末和控制污染物颗粒排放的工艺条件。利用高挥发分前驱体，初步研究了二氧化硅(SiO_2)、二氧化钛(TiO_2)、氧化铝(Al_2O_3)和氧化锆(ZrO_2)等陶瓷纳米粉末。被调查的污染物颗粒物是烟尘和含有铅(铅)和铬(铬)等有毒金属的颗粒物。综合研究计划涉及施加电场对火焰中固体颗粒形成的影响，并同时解决材料合成和环境工程方面的问题。在空气动力学简单流场，即平焰驻点(预混)和平焰逆流(非预混)中进行了实验，以表征电场和其他可控工艺参数(包括压力)对化学成分、一次颗粒尺寸、结晶度和团聚程度的影响。使用多种前驱体来制备掺杂、包覆或混合的纳米晶纳米颗粒。从成分、形貌、沉积方式和烧结等方面考察了电场作用下薄膜的沉积特性。利用先进的激光诊断技术、电子显微镜和X射线衍射法对火焰结构(由于工艺输入)对颗粒演化的影响进行了模拟和分析。建立了包含详细的气相化学动力学和输运(包括电场效应)的计算模型，以及颗粒形成、生长和聚集的模型。在已经证明的纳米粉末的火焰合成过程中，施加电场的方法在精确控制初级颗粒尺寸、结晶度和聚集尺寸方面是最有前途的方法之一。同样的方法也可用于控制用于发电和焚烧的燃烧系统的颗粒排放。研究和实验设施被纳入新的材料、科学和工程课程，作为几个系之间的联合课程，并被纳入关于先进实验方法的研究生课程。作为罗格斯大学数学、科学和工程专业女性道格拉斯项目的一部分，通过支持本科生研究，增加了少数族裔和女性对工程学的参与。通过与行业、州和纳米材料研究中心合作，促进学生(高中、本科生和研究生水平)的高科技劳动力培训。