Indoor Environment Group, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
BASF Corporation, Iselin, NJ, USA.
Indoor Air. 2020 Nov;30(6):1283-1295. doi: 10.1111/ina.12695. Epub 2020 Jul 3.
Indoor air cleaning systems that incorporate CO sorbent materials enable HVAC load shifting and efficiency improvements. This study developed a bench-scale experimental system to evaluate the performance of a sorbent under controlled operation conditions. A thermostatic holder containing 3.15 g sorbent was connected to a manifold that delivered CO -enriched air at a known temperature and relative humidity (RH). The air stream was also enriched with 0.8-2.1 ppm formaldehyde. The CO concentration was monitored in real-time upstream and downstream of the sorbent, and integrated formaldehyde samples were collected at different times using DNPH-coated silica cartridges. Sorbent regeneration was carried out by circulating clean air in countercurrent. Almost 200 loading/regeneration cycles were performed in the span of 17 months, from which 104 were carried out at reference test conditions defined by loading with air at 25°C, 38% RH, and 1000 ppm CO , and regenerating with air at 80°C, 3% RH and 400 ppm CO . The working capacity decreased slightly from 43-44 mg CO per g sorbent to 39-40 mg per g over the 17 months. The capacity increased with lower loading temperature (in the range 15-35°C) and higher regeneration temperature, between 40 and 80°C. The CO capacity was not sensitive to the moisture content in the range 6-9 g/m , and decreased slightly when dry air was used. Loading isothermal breakthrough curves were fitted to three simple adsorption models, verifying that pseudo-first-order kinetics appropriately describes the adsorption process. The model predicted that equilibrium capacities decreased with increasing temperature from 15 to 35°C, while adsorption rate constants slightly increased. The formaldehyde adsorption efficiency was 80%-99% in different cycles, corresponding to an average capacity of 86 ± 36 µg/g. Formaldehyde was not quantitatively released during regeneration, but its accumulation on the sorbent did not affect CO adsorption.
采用 CO 吸附材料的室内空气净化系统可实现暖通空调负荷转移和效率提升。本研究开发了一种台架实验系统，以在受控操作条件下评估吸附剂的性能。恒温支架中装有 3.15g 吸附剂，与歧管相连，歧管以已知温度和相对湿度（RH）输送富含 CO 的空气。空气流还富含 0.8-2.1ppm 的甲醛。在吸附剂的上游和下游实时监测 CO 浓度，并使用涂有 DNPH 的硅胶管在不同时间采集集成甲醛样品。通过逆流循环清洁空气进行吸附剂再生。在 17 个月的时间内进行了近 200 次加载/再生循环，其中 104 次在参考测试条件下进行，即在 25°C、38%RH 和 1000ppm CO 的条件下加载空气，在 80°C、3%RH 和 400ppm CO 的条件下再生空气。在 17 个月的时间里，工作容量从每克吸附剂 43-44mg CO 略有下降至 39-40mg CO 。容量随较低的加载温度（15-35°C）和较高的再生温度（40-80°C）而增加。CO 容量对 6-9g/m 3 范围内的湿度不敏感，当使用干燥空气时，容量略有下降。加载等温穿透曲线拟合到三个简单的吸附模型，验证了拟一级动力学很好地描述了吸附过程。该模型预测，从 15 到 35°C 时，平衡容量随温度升高而降低，而吸附速率常数略有增加。在不同循环中，甲醛的吸附效率为 80%-99%，对应的平均容量为 86±36µg/g。在再生过程中甲醛没有被定量释放，但它在吸附剂上的积累不会影响 CO 的吸附。
