Development of A Thermal Regeneration Method of Organic Vapor Respirator Cartridges

有机蒸气呼吸药筒对极性和高挥发性化合物的穿透时间一般较短，因为它们对活性碳的吸附能力较弱。这种较低的吸附亲和力成分可以容易地通过加热解吸。研究了吸附单一组分(甲醇、丙酮、异丙醇(IPA)、乙酸甲酯或甲乙酮)和双组分(IPA-甲苯或乙酸甲酯-甲苯)气体的呼吸机药筒的热再生特性，将水蒸气引入呼吸机药筒(重松公司，CA-104NII)，得到了穿透曲线。在检测到突破后，加热滤芯，通过连续供气获得脱附曲线。在脱附温度为65℃，空气流量为20 L/min的条件下，考察了循环对穿透时间的影响。在单一组分中，当脱附空气的相对湿度较低时，再生柱的穿透时间比新的短，但当相对湿度大于50%(在25℃时)时，穿透时间没有显著变化。在这两种情况下，在重复吸附-解吸循环后，再生柱上的突破时间没有显著变化。在双组分混合体系中，当较早的突破组分(IPA或乙酸甲酯)超过突破点时，解吸开始。较早穿透组分的穿透时间随吸附-脱附循环次数的增加而减小，但循环5次以上后基本保持不变。

The breakthrough time of organic vapor respirator cartridges for polar and high volatile compounds is generally short because of their weak adsorption affinity to activated charcoal. Such lower adsorption affinity component may easily desorb by heating. In this study, thermal regeneration characteristics of a respirator cartridge that adsorbed single component of vapor (methanol, acetone, isopropyl alcohol (IPA), methyl acetate or methyl ethyl ketone) and two-component vapors (IPA -toluene or methyl acetate -toluene) were investigated.The vapor introduced into a respirator cartridge (Shigematsu works, CA-104NII), and the breakthrough curve was obtained. After the breakthrough was detected, the cartridge was heated and the desorption curve was obtained by supplying air continuously. This adsorption-desorption cycle was repeated and the effect of the cycle on the breakthrough time was investigated under the desorption temperature was up to 65℃ and the air flow rate was 20 L/min.In a single component, the breakthrough time on a regenerated cartridge was shorter than that on a new one when the relative humidity of desorption air was low, but there was no significant change when the relative humidity was greater than 50% (values at 25℃). In both cases, there was no significant change in the breakthrough time on a regenerated cartridge after the adsorption-desorption cycle was repeated. In the two-component mixture system, desorption was started when the earlier breakthrough component (IPA or methyl acetate), exceeded the breakthrough point. The breakthrough time of the earlier breakthrough component tended to decrease with the increasing adsorption-desorption cycle but it became almost constant after the cycle was repeated more than 5 times.