Balanay Jo Anne G, Bartolucci Alfred A, Lungu Claudiu T
a Environmental Health Sciences Program, Department of Health Education and Promotion , East Carolina University , Greenville , North Carolina.
J Occup Environ Hyg. 2014;11(3):133-43. doi: 10.1080/15459624.2013.816433.
Granular activated carbon (GAC) is currently the standard adsorbent in respirators against several gases and vapors because of its efficiency, low cost, and available technology. However, a drawback of GAC due to its granular form is its need for containment, adding weight and bulkiness to respirators. This makes respirators uncomfortable to wear, resulting in poor compliance in their use. Activated carbon fibers (ACF) are considered viable alternative adsorbent materials for developing thinner, light-weight, and efficient respirators because of their larger surface area, lighter weight, and fabric form. This study aims to determine the critical bed depth and adsorption capacity of different types of commercially available ACFs for toluene to understand how thin a respirator can be and the service life of the adsorbents, respectively. ACF in cloth (ACFC) and felt (ACFF) forms with three different surface areas per form were tested. Each ACF type was challenged with six concentrations of toluene (50, 100, 200, 300, 400, 500 ppm) at constant air temperature (23°C), relative humidity (50%), and airflow (16 LPM) at different adsorbent weights and bed depths. Breakthrough data were obtained for each adsorbent using gas chromatography with flame ionization detector. The ACFs' surface areas were measured by an automatic physisorption analyzer. The results showed that ACFC has a lower critical bed depth and higher adsorption capacity compared to ACFF with similar surface area for each toluene concentration. Among the ACF types, ACFC2000 (cloth with the highest measured surface area of 1614 ± 5 m(2)/g) has one of the lowest critical bed depths (ranging from 0.11-0.22 cm) and has the highest adsorption capacity (ranging from 595-878 mg/g). Based on these studied adsorption characteristics, it is concluded that ACF has great potential for application in respiratory protection against toluene, particularly the ACFC2000, which is the best candidate for developing thinner and efficient respirators.
颗粒活性炭（GAC）由于其高效、低成本以及现有技术，目前是防毒面具中用于吸附多种气体和蒸汽的标准吸附剂。然而，GAC因其颗粒形态存在一个缺点，即需要进行封装，这增加了防毒面具的重量和体积。这使得防毒面具佩戴起来不舒服，导致其使用时的依从性较差。活性炭纤维（ACF）因其较大的表面积、较轻的重量以及织物形态，被认为是开发更薄、更轻且高效防毒面具的可行替代吸附材料。本研究旨在确定不同类型市售ACF对甲苯的临界床层深度和吸附容量，以分别了解防毒面具可以多薄以及吸附剂的使用寿命。测试了布状（ACFC）和毡状（ACFF）的ACF，每种形态有三种不同的表面积。在恒定的空气温度（23°C）、相对湿度（50%）和气流（16 LPM）条件下，对每种ACF类型在不同的吸附剂重量和床层深度下，用六种浓度的甲苯（50、100、200、300、400、500 ppm）进行挑战。使用带有火焰离子化检测器的气相色谱法获取每种吸附剂的穿透数据。通过自动物理吸附分析仪测量ACF的表面积。结果表明，对于每种甲苯浓度，在表面积相似的情况下，ACFC的临界床层深度较低，吸附容量较高。在ACF类型中，ACFC2000（测得表面积最高为1614±5 m²/g的布状）具有最低的临界床层深度之一（范围为0.11 - 0.22 cm），且具有最高的吸附容量（范围为从595 - 878 mg/g）。基于这些研究的吸附特性，得出结论：ACF在针对甲苯的呼吸防护应用中具有巨大潜力，特别是ACFC2000，它是开发更薄且高效防毒面具的最佳候选材料。
