Journal of Hazardous Materials 241–242 (2012) 463–471 Contents lists available at SciVerse ScienceDirect Journal of Hazardous Materials jou rn al h om epage: www.elsevier.com/loc ate/jhazmat Catalytic removal of carbon monoxide over carbon supported palladium catalyst Avanish Kumar Srivastava a , Amit Saxena b , Dilip Shah a , T.H. Mahato a , Beer Singh a,∗ , A.R. Shrivastava a , P.K. Gutch a , C.P. Shinde c a Defence Research and Development Establishment, Jhansi Road, Gwalior-474002 (MP), India b Centre for Fire Explosive and Environmental Safety, Timarpur, Delhi-110054, India c School of Studies in Chemistry, Jiwaji University, Gwalior-474002 (MP), India h i g h l i g h t s ◮ Carbon supported palladium (Pd/C) catalyst was prepared. ◮ Catalytic removal of CO over Pd/C catalyst was studied under dynamic conditions. ◮ Effects of Pd %, CO conc., humidity, GHSV and reaction environment were studied. a r t i c l e i n f o Article history: Received 19 March 2012 Received in revised form 28 September 2012 Accepted 1 October 2012 Available online 8 October 2012 Keywords: Palladium Catalyst Carbon monoxide Oxidation Incipient wetness a b s t r a c t Carbon supported palladium (Pd/C) catalyst was prepared by impregnation of palladium chloride using incipient wetness technique, which was followed by liquid phase reduction with formaldehyde. There- after, Pd/C catalyst was characterized using X-ray diffractometery, scanning electron microscopy, atomic absorption spectroscopy, thermo gravimetry, differential scanning calorimetry and surface character- ization techniques. Catalytic removal of carbon monoxide (CO) over Pd/C catalyst was studied under dynamic conditions. Pd/C catalyst was found to be continuously converting CO to CO 2 through the cat- alyzed reaction, i.e., CO + 1/2O 2 → CO 2 . Pd/C catalyst provided excellent protection against CO. Effects of palladium wt%, CO concentration, humidity, space velocity and reaction environment were also studied on the breakthrough behavior of CO. © 2012 Elsevier B.V. All rights reserved. 1. Introduction Serious environmental implication of CO gas emission from automotive sources has stimulated a huge amount of pure and applied research directed at catalytic abatement of such emission. In order to remove CO from air streams through catalytic oxidation, several oxidants [1] such as hoolamite (I 2 O 5 + fuming H 2 SO 4 ), sil- ver permanganate, hopcalite, etc. have been developed and used. The hopcalite is a moisture sensitive catalyst and catalytic activ- ity is greatly reduced due to the presence of moisture in air [1]. Therefore, the main disadvantage associated with hopcalite is its poisoning due to water, which makes it to be unsuitable for use for longer duration under humid conditions. Other catalysts [2–4] such as CuO/CeO 2 , CuO x -CeO 2 -ZrO 2 and CuO/Al 2 O 3 have also been reported with good catalytic activity for ∗ Corresponding author. Tel.: +91 7512341148; fax: +91 7512341148. E-mail address: beerbs5@rediffmail.com (B. Singh). the oxidation of CO at about 200 ◦ C of optimal reaction tempera- ture. For CO oxidation on ruthenium based model catalysts, it has been observed that metallic ruthenium surface is not active for this reaction whereas ruthenium oxide has superior catalytic activity [5]. Turner et al. [6,7] have investigated CO oxidation on polycrys- talline wires of platinum, palladium and iridium at atmospheric pressures. Palladium is a widely used catalyst for oxidation of CO and volatile organic compounds. El-Shall and co-workers [8] have reported CO oxidation on 5% Pd/CeO 2 , ZrO 2 and SiO 2 . Many researchers have reported palladium as an efficient metal for the oxidation of CO over metal oxides support [9–11]. Matsushima et al. [12], and Zhang and Hu [13] have also discussed adsorption and oxi- dation of CO on palladium in detail. Pd supported NaZSM-5 zeolite catalyst for CO oxidation showed 50 and 100% CO conversion at 38 and 90 ◦ C, respectively. [14]. Recently Li et al. [15] prepared 10% Pd supported graphene catalyst which showed 100% CO conversion at 110 ◦ C. Pd/Al 2 O 3 calcined at different temperature from 400 to 1200 ◦ C showed decrease in catalytic activity for CO oxidation and increase of optimal reaction temperature from 140 to 200 ◦ C [16]. 0304-3894/$ – see front matter © 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jhazmat.2012.10.001