工作场所空气中四氢化硅的职业接触限值的探讨和检测方法的研究

发布时间：2018-03-21 03:47

本文选题：四氢化硅　切入点：职业接触限值　出处：《华中科技大学》2012年硕士论文　论文类型：学位论文

【摘要】：四氢化硅是一种常见的工业原料，是提供硅组分的重要气体源，可用于制造高纯度单晶硅、多晶硅、异质硅、微晶硅、非晶硅、氮化硅、氧化硅等各种硅化物。四氢化硅在过渡温度17K（热力学温度单位）和极高的压力下（96和120GPa）可作为超导体使用[1]。由于四氢化硅的高纯度和能实现精细控制，，已经成为许多其他硅源无法取代的重要特种气体[2-3]。四氢化硅目前在电子工业、能源工业、玻璃工业、化学工业及高科技领域等多个行业中均被大量使用[4]。既往研究显示四氢化硅的主要毒性是刺激作用，有研究显示它可对皮肤、眼睛和呼吸道产生强烈刺激作用，造成对作业人员的健康危害[5-6]，但是，目前我国尚未制定工作场所空气中四氢化硅的职业接触限值和检测方法。为保护工人健康和预防职业危害，制订工作场所空气中四氢化硅的职业接触限值十分重要。本研究在查阅相关文献的基础上，进行了工作场所空气中四氢化硅的职业接触限值的探讨和检测方法的研究。本研究主要包括两部分：第一部分：工作场所空气中四氢化硅的职业接触限值的探讨目前，世界上有美国、加拿大、澳大利亚、日本等近20个国家制定了工作场所空气中四氢化硅的职业接触限值。其中将近三分之二的国家将工作场所空气中四氢化硅的8小时时间加权平均容许浓度定为(PC-TWA)为7mg/m~3；其余的国家将工作场所空气中四氢化硅的8小时时间加权平均容许浓度定为(PC-TWA)为0.7mg/m~3。通过查阅文献，结合四氢化硅的化学特性、毒性实验资料、人群流行病学资料，以及企业生产过程中四氢化硅实际水平测定，建议我国工作场所空气中的四氢化硅时间加权平均容许溶度(PC-TWA)为7mg/m~3。第二部分：工作场所空气中四氢化硅检测方法的研究目前国内外检测四氢化硅的方法主要有原子吸收分光光度计法、气相色谱法、紫外分光光度法、直读仪法。这几种方法实施起来均有一定的局限性，我国尚未制定测定四氢化硅的标准方法，本研究在仔细分析相关测定方法的基础上，进行了分光光度计法测定四氢化硅含量的研究。本方法原理为：用碱性树脂基球形活性炭管采集空气中的四氢化硅，经热水解吸，转化为偏硅酸钠，在酸性溶液中，偏硅酸钠转化为偏硅酸，并与钼酸铵反应，生成硅钼杂多酸，再用1，2，4-氨基萘酚磺酸溶液将硅钼杂多酸还原为硅钼蓝，在680nm波长下测量吸光度，进行定量。本方法的主要测定步骤为：用碱性树脂基球形活性炭管采集空气中的四氢化硅，将活性炭取出并用热水解吸，吸取适量的解吸液于15mL聚乙烯管中，用水稀释。加入盐酸溶液和钼酸铵溶液，充分摇匀，于水浴中放置10min，加入草酸溶液，充分摇匀，放置2min～15min，加入1，2，4-氨基萘酚磺酸溶液，充分摇匀。5min后，于分光光度计上680nm波长处，以试剂空白作参比测定吸光度。本方法的平均采样效率为97.53%，平均解吸效率为94.94%，穿透容量＞0.84mg/300mg，检出限为0.054μg/mL，定量下限为0.18μg/mL，最低检测浓度为1.2mg/m~3（以采样3.0L计算），随着碱性树脂基球形活性炭放置时间的延长，四氢化硅的转换率逐渐降低，采过的样品在室温下密封保存后一周下降率10%。本方法经武汉市职业病防治院、华中科技大学同济医学院和武汉市职业病医院三家单位验证，同时也在现场进行了验证，表明该测定方法重复性好、简单可行、结果准确、可用于现场检测。结论: 通过工作场所空气中四氢化硅职业接触限值和检测方法研究，得出以下主要结论： 1、建议我国工作场所空气中的四氢化硅时间加权平均容许溶度(PC-TWA)为7mg/m~3。 2、测定方法中，四氢化硅采样用活性炭浸渍氢氧化钠真空干燥后最好在一天内使用，或者将活性炭在真空状态下保存。现场采集样品密封保存在室温下至少可保存一周。 3、用分光光度计检测四氢化硅含量的方法其各项指标均达到《作业场所空气中毒物检测方法的研制规范》（GBZ159-2004）的要求，适用于作业场所空气中四氢化硅的测定。
[Abstract]:Four hydrogenated silicon is a common industrial raw materials, is to provide an important source of gas silicon components, can be used in the manufacture of high purity silicon, polycrystalline silicon, silicon heterojunction, microcrystalline silicon, amorphous silicon, silicon nitride, silicon oxide and other silicide. Four hydrogenated silicon in the transition temperature of 17K (thermodynamic temperature units) and high pressure (96 and 120GPa) can be used assuperconductor four [1]. due to the high purity silicon hydride and can achieve precise control, has become many other silicon sources can not replace important special gas hydrogenation of [2-3]. four silicon currently in the electronics industry, energy industry, glass industry, chemical industry and many industries such as high-tech fields are used extensively by the [4]. previous studies showed that the main toxicity of four hydrogenated silicon is stimulated, studies have shown it to the skin, eyes and respiratory tract have a strong stimulating effect, causing health hazards to workers [5-6], but. China has not yet formulated before the occupation exposure to workplace air four hydrogenated silicon limits and testing methods. In order to protect the health of workers and the prevention of occupation hazards, occupation contact four hydrogenated silicon made in the air of workplace limits is very important. This study on the basis of literature review, the research value and detection method the occupation exposure in the air of workplace four hydrogenated silicon limit. This study mainly includes two parts:
The first part: Discussion on the occupational exposure limit of four hydrogenated silicon in the air of the workplace
At present, the United States, Canada, Australia and the world, nearly 20 countries such as Japan made contact in the air of workplace occupation four hydrogenated silicon limits. The 8 hour time weighted nearly 2/3 countries will work four silicon in workplace air average concentration is 7mg/m~3 (PC-TWA) for 8 hours; the rest of the country will be weighted four hydrogenated silicon in workplace air as the average concentration (PC-TWA) of 0.7mg/m~3. through the literature, combined with the chemical properties of four hydrogenated silicon, toxicity data, epidemiological data, determination of four hydrogenated silicon actual level and the enterprise production process, suggestions for China's workplace four silicon time the air in the weighted average allowable (PC-TWA) 7mg/m~3. solubility
The second part: Study on the method of detecting four hydrogenated silicon in the air of the workplace
At present the four detection methods are mainly silicon hydride atomic absorption spectrophotometry, gas chromatography, UV spectrophotometry, direct reading instrument method. These methods implement have certain limitations, our country has not yet developed the standard method for the determination of four hydrogenated silicon, the basic research in the related careful analysis method, studied the spectrophotometric determination of silicon content of four hydrogenation meter.
The principle is: four silicon hydrogenation collected in air using alkaline resin based spherical activated carbon tube, hot water, into sodium metasilicate, in acidic solution, sodium metasilicate into silicic acid, and reacted with ammonium molybdate to form silicon molybdenum heteropoly acid, then 1,2,4- amino naphthalene phenol sulfonic acid solution silicon molybdenum heteropoly acid reduction of silicon molybdenum blue, quantitative measurement of the absorbance at the wavelength of 680nm.
The main steps of the method for the determination of silicon hydride: four collected in air using alkaline resin based spherical activated carbon tube, remove activated carbon and water desorption, the appropriate amount of desorption in 15mL polyethylene pipe, diluted with water. Add hydrochloric acid solution and ammonium molybdate solution, fully shaken, placed in water bath 10min the addition of oxalic acid solution, shake well, place the 2min ~ 15min, adding 1,2,4- amino naphthol sulfonic acid solution, shake well after.5min, spectrophotometer at the wavelength of 680nm, to determine the absorbance of reagent blank as reference.
The method of the average sampling efficiency was 97.53%, the average desorption efficiency was 94.94%, the penetration capacity of more than 0.84mg/300mg, the detection limit is 0.054 g/mL, the lower limit of quantification was 0.18 g/mL, the minimum detectable concentration was 1.2mg/m~3 (3.0L, by sampling calculation) with the extension of basic resin based spherical activated carbon placed time, conversion of four hydrogenated silicon the rate decreased gradually, decreased rate of 10%. extraction samples were sealed and stored at room temperature after a week
The method was verified by three units of Tongji Medical College, Wuhan Tongji Medical College and Wuhan occupational disease hospital. Meanwhile, it was also verified at the scene. The results showed that the method is repeatable, simple, feasible and accurate, and it can be used for field detection.
Conclusion:
Through the study of the occupational exposure limit and detection method of four hydrogenated silicon in the air of the workplace, the following main conclusions are drawn:
1, it is suggested that the time weighted average permissible solubility (PC-TWA) of the four hydrogenated silicon in the air of the workplace of our country is 7mg/m~3.
2, in the determination method, four hydrogenated silicon sample was impregnated with activated carbon and sodium hydroxide. After vacuum drying, it was best to use in a day or save the activated carbon in vacuum. The field samples were sealed and kept at room temperature for at least one week.
3, using spectrophotometer to detect the content of four hydrogenated silicon, all of the indicators meet the requirements of < < specification for detection of toxic substances in workplace air > > (GBZ159-2004), which is suitable for the determination of four hydrogenated silicon in the air of workplace.

【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R134.4

【参考文献】