Room temperature carbon monoxide removal catalyst and method for manufacturing the same

Abstract

A carbon monoxide removal catalyst is provided, comprising: a titania support; and an active component comprising platinum and niobium supported on the titania support.

Description

Technology Field

[0001] The present invention relates to a room temperature carbon monoxide removal catalyst and a method for manufacturing the same, and more specifically, to a room temperature carbon monoxide removal catalyst capable of removing / treating high concentrations of carbon monoxide at room temperature and a method for manufacturing the same. Background Technology

[0002] As modern people spend more time indoors, the importance of indoor air quality is becoming a social issue. Various pollutants exist indoors, among which carbon monoxide and formaldehyde are highly harmful to the human body, and their risks and impacts are serious.

[0003] In the case of carbon monoxide, poisoning and fatal accidents are frequently reported in the surrounding area, with an average of 1.2 casualties per accident and an average victim rate of 1.3 over five years; it is reported that 6 out of 11 total gas-related deaths in Korea were caused by carbon monoxide poisoning. Along with carbon monoxide, formaldehyde is a major causative agent of sick building syndrome, sick house syndrome, and chemical sensitivity, and accounts for the largest amount among aldehydes generated indoors. Exposure to formaldehyde in the human body causes eye irritation, tearing, upper respiratory tract irritation, asthma attacks, convulsions, vomiting, and diarrhea, and it is known to have a more sensitive impact on vulnerable groups such as pregnant women, children, and the elderly.

[0004] There are various conventional technologies for treating pollutants present indoors, and among them, the oxidation method using a catalyst is known to be the best method because it converts pollutants into substances harmless to the human body, thereby eliminating the generation of secondary pollutants and the need for regeneration. However, existing carbon monoxide oxidation catalysts face many limitations in use due to problems such as catalyst poisoning and deactivation caused by carbonates generated during the CO removal process, as well as the resulting decrease in durability. Additionally, it is noted that they are economically unviable because they require a large amount of catalyst due to operation at low space velocities.

[0005] Therefore, there is a need to develop a new room-temperature catalyst capable of removing carbon monoxide even under high-concentration conditions without the effects of poisoning. Prior art literature

[0007] 1. Republic of Korea Published Patent No. 10-2019-0049285 2. Republic of Korea Registered Patent No. 10-998325 3. Republic of Korea Registered Patent No. 10-1629484 The problem to be solved

[0008] Therefore, the problem that the present invention aims to solve is to provide a new catalyst that exhibits excellent removal activity at room temperature even under conditions of high concentrations of carbon monoxide, and a method for manufacturing the same. means of solving the problem

[0009] To solve the above problem, the present invention provides a carbon monoxide removal catalyst comprising: a titania support; and an active component comprising platinum and niobium supported on the titania support.

[0010] In one embodiment of the present invention, the surface oxygen species of the carbon monoxide removal catalyst is 20% or more, and the niobium is 0.5 to 3 weight percent of the catalyst.

[0011] In one embodiment of the present invention, the particle size of the catalyst is 1.5 nm or less, and the distribution of the active component is 60% or more. Effects of the invention

[0012] According to the present invention, a carbon monoxide removal catalyst comprising niobium as a co-catalyst according to the present invention can convert and remove high concentrations of carbon monoxide, such as 500 ppm or more present at room temperature, into carbon dioxide. In addition, by adding niobium as a co-catalyst to Pt / TiO2, the durability against carbon monoxide is increased, and at the same time, the catalyst is less poisoned by nitrogen oxides, which act as a poisoning factor, and can be applied not only at room temperature but also at low temperatures of 100°C or lower. Brief explanation of the drawing

[0013] Figure 1 shows the results of a carbon monoxide removal experiment under conditions of simultaneous nitrogen oxide inflow. Figure 2 shows the results of a carbon monoxide removal experiment after reducing the platinum content from 1 wt% in Figure 1 to 0.5 wt%. Figure Figure 3 is the TEM analysis result for the catalyst according to the present invention and a comparative example. Figure 4 is the XPS analysis result for the catalyst according to the present invention and a comparative example. Figure 5 is the result of analyzing the oxygen characteristics of the catalyst through XPS analysis of the catalyst according to the present invention and a comparative example. Figure 6 is the result of CO-TPD analysis to confirm the degree of carbon dioxide desorption. Figure 7 shows the results of the carbon monoxide control performance analysis under the condition of simultaneous nitrogen oxide inflow. Figure 8 shows the TPD analysis results of nitrogen oxides (NOx) for the actual catalyst, and Table 3 shows a comparison of nitrogen oxide desorption characteristics. Figure 9 shows the results of analyzing the active metal dispersion rate and carbon monoxide conversion rate according to Nb content. Specific details for implementing the invention

[0014] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. However, this is merely an example and the present invention is not limited thereto.

[0015] In describing the present invention, detailed descriptions of known technologies related to the invention are omitted if it is determined that such descriptions may unnecessarily obscure the essence of the invention. Furthermore, the terms described below are defined considering their functions in the present invention, and these definitions may vary depending on the intentions or practices of the user or operator. Therefore, their definitions should be based on the content throughout this specification.

[0016] The technical concept of the present invention is determined by the claims, and the following embodiments are merely a means to efficiently explain the technical concept of the present invention to those skilled in the art to which the present invention belongs.

[0017] To solve the aforementioned problems, the present invention provides a carbon monoxide removal catalyst comprising: a titania support; and an active component comprising platinum and niobium supported on the titania support. In particular, by adding niobium as a co-catalyst to a platinum main catalyst, the present invention achieves high catalytic dispersion, excellent catalytic activity, and, in particular, high selectivity for carbon monoxide against nitrogen oxides.

[0018] Preparation Example

[0019] 2% by weight of niobium (Nb) is added to titania (G5), stirred with distilled water, and then the moisture is removed using an evaporator. Afterward, the temperature is raised to 600°C at a rate of 10°C per minute and maintained at 600°C for 4 hours. Then, PtOH is added to the prepared G5 / Nb mixture, stirred, and the moisture is removed using an evaporator. The temperature is raised to 400°C at a rate of 10°C per minute and maintained at 400°C for 4 hours. Afterward, the prepared G5 / Nb / Pt mixture is raised to 600°C at a rate of 10°C per minute and maintained at 600°C for 1 hour to perform hydrogen reduction.

[0021] Experimental example

[0022] Figure 1 shows the results of a carbon monoxide removal experiment under conditions of simultaneous nitrogen oxide inflow.

[0023] The experimental conditions in Fig. 1 are CO 500 ppm, O2 21%, RH 55%, SV 40,000 hr -1 It was.

[0024] Referring to Figure 1, it was confirmed that when Nb was added as a co-catalyst to TiO2 (G-5) under conditions of high concentration (500 ppm) carbon monoxide inflow, it had a high reaction activity of over 90% even when the Pt content was reduced to 0.5% compared to the other two Pt-based catalysts.

[0025] Figure 2 shows the results of a carbon monoxide removal experiment after reducing the platinum content from 1 wt% in Figure 1 to 0.5 wt%. The experimental conditions in Figure 2 are the same as those in Figure 1.

[0026] Referring to Figure 2, it can be confirmed that when Nb is added as a co-catalyst to TiO2 (G-5) under conditions of high concentration (500 ppm) carbon monoxide inflow, it has a high reaction activity of about 90% or more even when the Pt content is reduced to 0.5 wt% compared to the other two Pt-based catalysts.

[0027] delete

[0028] Figure 3 is the result of TEM analysis.

[0029] Referring to Figure 3, it can be seen that the particle size was reduced by adding Sb and Nb as co-catalysts, and in particular, the particle size of the catalyst with added Nb was found to be less than 1.5 nm on average (see figure below).

[0030] The present invention also performed CO-Pulse chemisorption analysis to determine the distribution of active metals, and the results are shown in Table 1 below.

[0031] [Table 1]

[0032]

[0033] Referring to the above results, it can be seen that the distribution of active metals in the catalyst with added Nb increased significantly to about 63%, and the active particle size became smaller than 1.5 nm compared to the other two catalysts.

[0034] Figure 4 shows the XPS analysis results, and Table 2 below shows the SMSI characteristic analysis results through XPS analysis.

[0035] [Table 2]

[0036]

[0037] Referring to Figure 4 and Table 1, the Pt binding energy of the catalyst with Sb and Nb added as co-catalysts shifted to a lower level compared to the Pt / TiO2 catalyst, and the degree of shift of the Pt / Nb / TiO2 catalyst was confirmed to be about 0.22, which is a large level compared to the other two catalysts.

[0038] Figure 5 shows the results of the analysis of the oxygen characteristics of the catalyst through XPS analysis, and Table 3 shows the results of the comparison of the oxygen characteristics of the catalyst through XPS analysis.

[0039] Referring to Figure 5 and Table 3, it was confirmed that in the case of the catalyst with Nb added as a co-catalyst, the surface oxygen species were present at a high level of 23.6% compared to the other two catalysts (see figure below).

[0040] Figure 6 is the result of CO-TPD analysis to confirm the degree of carbon dioxide desorption.

[0041] Referring to Figure 6, it was confirmed that in the case of a catalyst with Sb and Nb added as co-catalysts, carbon monoxide was converted into carbon dioxide and desorbed at a lower temperature. In other words, when a co-catalyst is added, the bonding strength of carbon monoxide is weakened, and desorption into carbon dioxide using surface oxygen at a lower temperature can be facilitated.

[0042] Figure 7 shows the analysis results of carbon monoxide control performance under conditions of simultaneous nitrogen oxide inflow. In Figure 7, the conditions are CO 100 ppm, NO 5 ppm, O2 21%, RH 55%, SV 120,000 hr -1 It was.

[0043] Referring to Fig. 7, it can be confirmed that under conditions of simultaneous influx of carbon monoxide and nitrogen oxides, only the catalyst supported with Nb as a co-catalyst on TiO2 (G5) shows a reaction activity that is reduced to 10% or less compared to the condition of carbon monoxide alone.

[0044] Figure 8 shows the TPD analysis results of nitrogen oxides (NOx) for the actual catalyst, and Table 3 shows a comparison of nitrogen oxide desorption characteristics.

[0045] Referring to Figure 8 and Table 3, it can be seen that in the case of the niobium (Nb) added catalyst according to the present invention, the amount of NOx adsorbed on the comparative example PtO is small, so the poisoning effect caused by nitrogen oxides can be minimized even under conditions of simultaneous influx with carbon monoxide (refer to the blue graph in Figure 8).

[0046] [Table 3]

[0047]

[0048] Figure 9 shows the results of analyzing the active metal dispersion rate and carbon monoxide conversion rate according to Nb content. The experimental conditions in Figure 9 are the same as those in Figure 1.

[0049] Referring to FIG. 9, in the case of a catalyst with Nb added as a co-catalyst, as the Nb content increases up to 2%, the distribution of platinum, which is an active metal, increases and the conversion rate of carbon monoxide to carbon dioxide increases; however, when supported at 3% or more, it can be confirmed that the distribution of the active metal decreases and the conversion rate decreases significantly. Therefore, the niobium content in the catalyst according to the present invention is 0.5 wt% to 3 wt%, more preferably 1 wt% or more and less than 3 wt%.

Claims

Claim 1 award A room temperature carbon monoxide removal catalyst comprising: a titania support; and an active component comprising platinum and niobium, which are co-catalysts supported on the titania support, wherein the niobium is 0.5 to 3 weight% of the catalyst, and the niobium is supported on the titania support. On the titania support on which the niobium is supported, the platinum is supported with platinum hydroxide (PtOH) and then reduced, wherein the particle size of the catalyst is 1.5 nm or less, the distribution of the active component is 60% or more, and the surface oxygen species of the carbon monoxide removal catalyst is 20% or more. Claim 2 A room temperature carbon monoxide removal catalyst characterized by a reduction in carbon monoxide conversion rate of 10% or less under conditions where carbon monoxide and nitrogen oxides coexist, according to claim 1. Claim 3 delete Claim 4 delete Claim 5 delete

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