Improved removal of indoor volatile organic compounds by activated carbon fiber filters calcined with copper oxide catalyst

Abstract

Heating, ventilating, and air-conditioning (HVAC) systems ensure indoor air quality and provide a comfortable environment. However, the conventional HVAC systems only provide indoor ventilation and adjust temperature and humidity. This work removes indoor volatile organic compounds (VOCs) using a feasible and novel air-cleaning for an HVAC system, to remove indoor VOCs. An activated carbon-fiber (ACF) filter calcined with copper oxide (CuO) catalyst, called a CuO/ACF catalyst filter, was the developed kit. Formaldehyde, a major VOC, was chosen as the target pollutant. Experiments were performed to confirm the filtration ability of the CuO/ACF catalyst filter in removing formaldehyde in a stainless-steel chamber equipped with a simplified HVAC system. Total air exchange rate (ACH) was controlled at 0.5 and 1.0 h-1, the fresh ACH was 0.15 and 0.30 h-1, and relative humidity (RH) was set at 30 and 70%. A first-order decay of formaldehyde existed in the controlled chamber when the two pretreated CuO/ACF catalyst filters were employed. Experimental results demonstrate that the CuO/ACF catalyst filters removed formaldehyde effectively. The decay constant was 0.425 and 0.618 h-1 for 0.5 and 2.0 ppm formaldehyde, respectively. Moreover, the formaldehyde decay rate increased as total ACH, fresh ACH, RH, and the Cu(NO3)2 concentration for calcination of CuO/ACF catalyst filter increased.The results indicate that the oxidization capability of the CuO catalyst of the CuO/ACF catalyst filter has a major effect on formaldehyde removal. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.