Denitration Catalyst Research Articles

An anti-poisoning defective catalyst without metal active sites for NH3-SCR via in situ stabilization

The denitrification catalyst without metal active component has excellent anti-poisoning performance and stability.

Low-temperature NH3-SCR performance of a novel Chlorella@Mn composite denitrification catalyst

The synthesis process of conventional Mn-based denitrification catalysts is relatively complex and expensive. In this paper, a resource application of chlorella was proposed, and a Chlorella@Mn composite denitrification catalyst was innovatively synthesized by electrostatic interaction. The Chlorella@Mn composite denitrification catalyst prepared under the optimal conditions (0.54 g/L Mn2+ concentration, 20 million chlorellas/mL concentration, 450°C calcination temperature) exhibited a well-developed pore structure and large specific surface area (122 m2/g). Compared with MnOx alone, the Chlorella@Mn composite catalyst achieved superior performance, with ∼100% NH3 selective catalytic reduction (NH3-SCR) denitrification activity at 100-225°C. The results of NH3 temperature-programmed desorption (NH3-TPD) and H2 temperature-programmed reduction (H2-TPR) showed that the catalyst had strong acid sites and good redox properties. Zeta potential testing showed that the electronegativity of the chlorella cell surface could be used to enrich with Mn2+. X-ray photoelectron spectroscopy (XPS) confirmed that Chlorella@Mn had a high content of Mn3+ and surface chemisorbed oxygen. In-situ diffuse reflectance infrared Fourier transform spectroscopy (in-situ DRIFTS) experimental results showed that both Langmuir-Hinshelwood (L-H) and Eley-Rideal (E-R) mechanisms play a role in the denitrification process on the surface of the Chlorella@Mn catalyst, where the main intermediate nitrate species is monodentate nitrite. The presence of SO2 promoted the generation and strengthening of Brønsted acid sites, but also generated more sulfate species on the surface, thereby reducing the denitrification activity of the Chlorella@Mn catalyst. The Chlorella@Mn composite catalyst had the characteristics of short preparation time, simple process and low cost, making it promising for industrial application.

Study on Precipitation Kinetics of Calcium Pyro-Vanadate and Thermodynamics of Vanadium Water System

Selective catalytic reduction (SCR) is a technology widely used in large coal-fired units to remove nitrogen oxides from flue gas, but it also generates a large number of waste catalysts every year. At present, the recovery of V from discarded SCR catalysts has good application prospects and environmental significance. In this paper, the kinetics and thermodynamics of vanadium precipitation process are described with the vanadium-containing liquid of waste denitration catalyst recovered by alkali leaching as raw material and CaCl2 as precipitant in order to further explore the mechanism of vanadium precipitation. The kinetics study showed that the crystallization process of calcium pyrovanadate can be well-described by Avrami kinetic model when the precipitation time is 95–130 min, and the vanadium precipitation temperature is 60–80 °C. After that, the Arrhenius equation was used to analyze the fitted kinetic data, and the apparent activation energy Ea of vanadium precipitation reaction was calculated to be 98.196 kJ/mol, and the pre exponential factor A = 8.59 × 1039 min−1. Thermodynamic study showed that when the pH of the vanadium water system is low, the +5 valence vanadium in the solution mainly exists in the form of VO2+ cation. When the pH is between 0–1, the solubility of vanadium reaches the minimum and then increases the solution pH again, and various polymerized anions are formed in the vanadium water system. When the temperature is 25 °C, the activity of vanadium in vanadium-containing solution is 10−1, the pH of solution is 8–12, and the existence form of +5 valence vanadium in solution is mainly HV2O73−. By analyzing the existing forms of V with different activities in a vanadium water system at 25 °C, it can be seen that with the decrease of V activity in liquid, the dominant region of polymerized vanadium-containing species in the potential pH diagram will disappear, indicating that vanadium mainly exists in the form of mononuclear ions in low-concentration vanadium-containing solutions, which is not conducive to precipitation. Therefore, in the process of precipitation of vanadium in solution, the concentration of V should be increased as much as possible.

Effect of Hydroxylation and Carboxylation on the Catalytic Activity of Fe2O3/Graphene for Oxidative Desulfurization and Denitration

Iron-based particles loaded on porous carbon materials have attracted extensive attention as catalysts for denitration and desulfurization reactions. However, the carbon support of a high-temperature denitration catalyst is inevitably oxidized in the presence of H2O and O2. The mechanism of denitration catalyst oxidation and its influence on the catalytic reaction remain to be further explored. Fe2O3-loaded graphene models with carbon vacancy (Gdef), hydroxyl (HyG), and carboxyl (CyG) were constructed to investigate the effects of hydroxylation and carboxylation on the catalytic activity of Fe2O3/graphene for oxidative desulfurization and denitration by using density functional theory (DFT) calculations. According to the analysis of structural properties and adsorption energy, the adsorption process of Fe2O3 on HyG and CyG was observed to have proceeded more favorably than that on Gdef. The density-of-states (DOS) results also affirmed that HyG and CyG promote the electron delocalization of Fe2O3 around the Fermi level, enhancing the chemical activity of Fe2O3. Moreover, adsorption energy analysis indicates that hydroxylation and carboxylation enhanced the adsorption of SO2 and H2O2 on Fe2O3/graphene while also maintaining preferable adsorption stability of NO. Furthermore, mechanistic research explains that adsorbed H2O2 on HyG and CyG directly oxidizes NO and SO2 into HNO2 and H2SO4 following a one-step reaction. The results provide a fundamental understanding of the oxidized catalyst on catalytic denitration and desulfurization reactions.

Novel surface carbon–oxygen-groups grafted TiO2 for selective catalytic reduction of NOx by NH3 at low temperature

Activated coke (AC) with has excellent low-temperature NH3-SCR denitration performance due to its abundant surface-active functional groups including carbon species, while it is easy to burn during industrial application. Herein, a novel surface carbon–oxygen-groups grafted TiO2 was constructed by calcining the solid mixture of polyethylene glycol (PEG) and TiO2. The prepared 0.4PEG/0.6Ti catalyst shows good NH3-SCR denitration activity, and its NOx conversion was up to 80 % above 210 °C, while the pure AC exhibited poor activity. Characterization results suggest that the superior catalytic activity of 0.4PEG/0.6Ti catalyst is mainly attributed to the formation of lactone and carboxyl groups, which can promote the adsorption and activation of NO and NH3 species. Furthermore, NH3 as the reactant can also inhibit the decomposition of carbonyl groups due to over-oxidation, thus 0.4PEG/0.6Ti catalyst has good long-term stability. The reaction mechanism study reveals that the NH3-SCR reactions over catalysts follow the E-R and L-H mechanisms. Finally, the desulfurization-regeneration-denitration test (imitated activated coke simultaneous desulfurization and denitrification process) was carried out, and the results confirm that the prepared PEG/Ti catalyst could be regenerated for denitration after desulfurization. We expect that this work can provide some guidance for the design of low-temperature denitration catalysts.

The simultaneous removal of NO and SO2 over MnO2 material via the multi-stage fluidized bed process at low temperatures

To overcome the easy poisoning and deactivation of denitrification catalysts by SO2 at low temperatures, the bench-scale multi-stage fluidized bed (MSFB) process with the active MnO2 medium (feeding rate of 0.3–1.2 kg/h) is designed and applied to simultaneously remove the NO and SO2 from flue gas of medium/small industrial boilers in the low-temperature range of 100 – 200 °C, which demonstrates excellent and stable removal efficiency of both NO and SO2 even in the presence of 10 vol% water. In the MSFB system, the fluidized MnO2 particles in different layers flow against the simulated flue gas stage by stage, and the deactivated MnO2 will be continuously discharged and replaced with fresh MnO2 to keep the system effective and steady. The MnO2 medium acts as both denitrification (DeNOx) catalyst and desulfurizer, and the limited backmixing and layered arrangement of the MSFB system ensure the high removal capacity and sufficient utilization of MnO2 material. The multiple structural characterizations further reveal that the active MnO2 is gradually consumed by SO2 to form MnSO4 stage by stage with decreased specific surface and pore volume, accounting for its gradually decreased removal efficiency of both NO and SO2 stage by stage. And the deactivated MnO2 can be easily regenerated by aqueous ammonia with the conversion of MnSO4 to active MnO2. The demonstrated advantages of the MSFB system with MnO2 will provide a promising technical route for the simultaneous removal of NO and SO2 from low-temperature flue gas in industry.

CeO2-doped WO3 composite catalyst based on acid site enhancement for diesel exhaust gas denitration

Based on the complicated preparation of current diesel vehicle exhaust gas denitration catalysts, an in-situ deposited composite oxide catalyst, CeO2-WO3 mixed oxide catalyst, was prepared by electrodeposition and hydrothermal methods, which was loaded on the titanium mesh and applied to the selective catalytic reduction denitration of diesel vehicle exhaust. Denitration performance of the catalysts was tested by a fixed bed reactor, and the influence of different electrodeposition time of CeO2 was investigated. The results demonstrate that 20 min is the best electrodeposition time of CeO2 (100% NOx conversion at 250–350 °C). The high dispersion of active CeO2 on WO3 promotes the synergistic effects among different components. The as-prepared catalysts were characterized by SEM, XRD, XPS, H2-TPR, NH3-TPD and in-situ DRIFTS. It is evident that Ce3+ is successfully introduced by loading CeO2, which enhances the chemisorption of oxygen. Meanwhile, the increased acidity including both weak acid and medium-strong acid sites of CeO2-WO3 composite catalyst is observed, which improves the co-adsorption of NH3 on Lewis acid and Brønsted acid simultaneously and facilitates the denitration process. Through the characterization by in-situ DRIFTS, it is elucidated that the NH3-SCR reactions are mainly carried out following the Eley-Rideal (E-R) pathway in a medium-temperature range (250–350 °C).

Separation of vanadium and tungsten in roasting‐acid leaching solutions of the spent selective catalytic reducing denitration catalyst by co‐extraction using hydroxyoxime extractant‐quaternary ammonium salt extractant LIX984–N263 extractant

AbstractThis study presents a synergistic extraction and recovery of vanadium and tungsten by mixed extractants (LIX984 and N263) from an acid leaching solution which was obtained from spent denitrification catalysts by chlorination heat treatment and acid leaching. Through thrice counter‐flow extraction, 99.5% V and 99.7% W were extracted, while 3.0% Fe, 2.9% Ti, 2.1% P, and 3.3% Mg were co‐extracted at a LIX984:N263 volume content of 22.0%, the phase ratio of 2.5 and the mother liquor's pH of 2.5. Then, at 0.80 mol/l NaOH and a phase ratio of 1, 99.9% tungsten and 99.1% vanadium were stripped from the organic phase to the aqueous phase. Subsequently, the aqueous phase's tungsten of 99.3% and vanadium of 98.1% were separated as calcium tungstate and ammonium metavanadate, respectively. In contrast, the residual solutions containing tungsten and vanadium can be returned to the following purification separation process to recover the valuable metals from the solution. Roasting converts the precipitated calcium tungstate and ammonium metavanadate to V2O5 and WO3 products. In addition, the thermodynamic analysis found the separation and recovery of tungsten and vanadium from the acid leach solution with LIX984:N263 to be an exothermic process. This method can be effectively extended for the separation of vanadium and tungsten from spent denitrification catalysts by the proposed process and validates the conclusion that metals with similar properties can be extracted using a mixture of extractants.

Superior PbO-resistance of CeO2/ZrO2 catalyst promoted by solid superacid SO42−/ZrO2 for selective catalytic reduction of NOx with NH3

The serious deactivation of denitration catalysts caused by heavy metals still a thorny issue in the practical application of selective catalytic reduction of NOx with NH3. Herein, we proposed a novel anti-poisoning strategy by designing SO42−/ZrO2 superacid supported CeO2/ZrO2 catalyst, and the effect of SO42−/ZrO2 supported CeO2/ZrO2 for PbO-resistance NOx catalytic reduction was investigated. It was worthy to note that the introduction of solid superacid SO42−/ZrO2 significantly enhanced catalytic performance over the entire temperature range, with an exceptionally high NOx removal efficiency over 98 % during 250–500 °C. When 2 wt% PbO was deposited on the fresh catalyst, the catalytic activity of CeO2/ZrO2 catalyst decreased obviously, while CeO2/ZrO2-S catalyst can still maintain a higher NOx conversion over 90 % from 275 to 500 °C. The characterization results confirmed that the introduction of solid superacid SO42−/ZrO2 enhanced the surface acidity and promoted the transformation from Ce4+ to Ce3+. The results of in situ DRIFTS implied that the Eley-Rideal (E-R) mechanism was obeyed over CeO2/ZrO2 catalyst, and both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms were followed over CeO2/ZrO2-S catalyst in the SCR process. With regard to poisoned catalysts, the NH3 adsorption was inhibited to some extent, while the reaction mechanism wasn’t changed by PbO poisoning.

Iron-based denitration catalyst derived from Fenton sludge: Optimization analysis of selective dealkalization and influence mechanism of calcination temperature

Fenton sludge from sewage treatment plants is a kind of hazardous waste that causes serious harm to the ecological environment. In this study, the potential of preparing a novel selective catalytic reduction (SCR) denitration (deNOx) catalyst was evaluated through selective dealkalization followed by calcination using Fenton sludge. The effects of water leaching, carbon dioxide leaching, and acid leaching methods (organic and inorganic acid) on Fenton sludge dealkalization were studied, taking the total dealkalization and active component retention rates and deNOx efficiency as comprehensive considerations. Results showed that acid leaching method has the best leaching effect on free alkali and chemically combined alkali, the order of dealkalization rates was FSH2SO4 (94.23%)>FSHCl (92.18%)>FSHNO3 (89.93%)>FSCH3COOH (81.07%). Through comprehensive comparison, FSHCl exhibited the best catalytic active and excellent selective dealkalization performance, achieving relatively high total dealkalization rate while retaining the active components to the greatest extent (86.73%). On this basis, the effects of calcination temperature on catalytic activity, as well as physical and chemical properties of the catalyst were studied. The MFS-450 catalyst exhibited the largest surface area (76.53 m2/g), pore volume (0.23 cm3/g), abundant oxygen-containing functional groups, excellent surface acidity (0.779 μmol/m2), and redox properties (5.07 mmol/g). Besides, it has the best low-temperature SCR activity and the widest reaction temperature window, with nitrogen oxide (NOx) conversion exceeding 90% at temperatures between 293 and 471 °C. This research contributes a representative example of converting Fenton sludge into valuable materials and may open a new avenue to synthesizing high-activity SCR catalyst from low-cost feedstocks.

Advances in air pollution control for key industries in China during the 13th five-year plan

Industrial development is an essential foundation of the national economy, but the industry is also the largest source of air pollution, of which power plants, iron and steel, building materials, and other industries emit large amounts of pollutants. Therefore, the Chinese government has promulgated a series of stringent emission regulations, and it is against this backdrop that research into air pollution control technologies for key industrial sectors is in full swing. In particular, during the 13th Five-Year Plan, breakthroughs have been made in pollution control technology for key industrial sectors. A multi-pollutant treatment technology system of desulfurization, denitrification, and dust collection, which applies to key industries such as power plants, steel, and building materials, has been developed. High-performance materials for the treatment of different pollutants, such as denitrification catalysts and desulfurization absorbers, were developed. At the same time, multi-pollutant synergistic removal technologies for flue gas in various industries have also become a hot research topic, with important breakthroughs in the synergistic removal of NOx, SOx, and Hg. Due to the increasingly stringent emission standards and regulations in China, there is still a need to work on the development of multi-pollutant synergistic technologies and further research and development of synergistic abatement technologies for CO2 to meet the requirements of ultra-low emissions in industrial sectors.

An overview of the deactivation mechanism and modification methods of the SCR catalysts for denitration from marine engine exhaust

Selective catalytic reduction (SCR) technology is currently the most effective deNOx technology and has broad application prospects. Moreover, there is a large NOx content in marine engine exhaust. However, the marine engine SCR catalyst will be affected by heavy metals, SO2, H2O(g), hydrocarbons (HC) and particulate matter (PM) in the exhaust, which will hinder the removal of NOx via SCR. Furthermore, due to the high loading operation of the marine engine and the regeneration of the diesel particulate filter (DPF), the exhaust temperature of the engine may exceed 600°C, which leads to sintering of the SCR catalysts. Therefore, the development of new catalysts with good tolerances to the above emissions and process parameters is of great significance for further reducing NOx from marine engines. In this work, we first elaborate on the mechanism of the SCR catalyst poisoning caused by marine engine emissions, as well as the working mechanism of SCR catalysts affected by the engine exhaust temperature. Second, we also summarize the current technologies for improving the properties of SCR catalysts with the aim of enhancing the resistance and stability under complex working conditions. Finally, the challenges and perspectives associated with the performance optimization and technology popularization of marine SCR systems are discussed and proposed further. Consequently, this review may provide a valuable reference and inspiration for the development of catalysts and improvement in the denitration ability of SCR systems matched with marine engines.

Progress of selective catalytic reduction denitrification catalysts at wide temperature in carbon neutralization.

With the looming goal of carbon neutrality and increasingly stringent environmental protection policies, gas purification in coal-fired power plants is becoming more and more intense. To achieve the NOx emission standard when coal-fired power plants are operating at full load, wide-temperature denitrification catalysts that can operate for a long time in the range of 260–420°C are worthy of study. This review focuses on the research progress and deactivation mechanism of selective catalytic reduction (SCR) denitration catalysts applied to a wide temperature range. With the increasing application of SCR catalysts, it also means that a large amount of spent catalysts is generated every year due to deactivation. Therefore, it is necessary to recycle the wide temperature SCR denitration catalyst. The challenges faced by wide-temperature SCR denitration catalysts are summarized by comparing their regeneration processes. Finally, its future development is prospected.

NO Reduction Reaction by Kiwi Biochar-Modified MnO2 Denitrification Catalyst: Redox Cycle and Reaction Process

NO is a major environmental pollutant. MnO2 is often used as a denitrification catalyst with poor N2 selectivity and weak SO2 resistance. Kiwi twig biochar was chosen to modify MnO2 samples by using the hydrothermal method. The NO conversion rates of the biochar-modified samples were >90% at 125–225 °C. Kiwi twig biochar made the C2MnO2 sample with a larger specific surface area, a higher number of acidic sites and Oβ/Oα molar ratio, leading to more favorable activity at high temperatures and better SO2 resistance. Moreover, the inhibition of the NH3 oxidation reaction and the Mn3+ → Mn4+ process played a crucial role in the redox cycle. What was more, Brønsted acidic sites present on the C1MnO2 sample participate in the reaction more rapidly. This study identified the role of biochar in the reaction process and provides a reference for the wide application of biochar.

Effects of Flue Gas Impurities on the Performance of Rare Earth Denitration Catalysts

Selective catalytic reduction (SCR) is still the most widely used process for controlling NOx gas pollution. Specifically, commercial vanadium-based catalysts have problems such as narrow operating temperature range and environmental pollution. Researchers have developed a series of cerium-based catalysts with good oxygen storage performance and excellent redox performance of CeO2. However, the anti-poisoning performance of the catalyst is the key to its application. There are many kinds of impurities in the flue gas, which has a huge impact on the catalyst. The deposition of substances, the reduction of active sites, the reduction of specific surface area, and the reduction of chemically adsorbed oxygen will affect the denitration activity of the catalyst to varying degrees, and the poisoning mechanism of different impurities on the catalyst is also different. Therefore, this review divides the impurities contained in flue gas into different types such as alkali metals, alkaline earth metals, heavy metals, and non-metals, and summarizes the effects and deactivation mechanisms of various types of impurities on the activity of rare earth catalysts. Finally, we hope that this work can provide a valuable reference for the development and application of NH3-SCR catalysts for rare earth denitration in the field of NOx control.

Ternary MnCoVOx catalysts with remarkable deNOx performance: Dual acid-redox sites control strategy

How to widen the active temperature window of metal oxide catalysts for abatement of NOx is urgent for their real application. Herein, a series of ternary MnCoVOx metal oxide catalysts with outstanding denitration performance were designed via a simple dual acid-redox sites tuning strategy, which is to inhibit the redox ability properly and enhance the acidity to make the catalyst exerts the optimum. The Mn0.50Co0.49V0.01Ox catalyst after vanadium tuning exhibited superior catalytic performance, achieving > 80% NOx conversion over a wide temperature window (162−508 °C) under the humid reaction condition, the selectivity of N2 > 85% up to 510 °C, and also displayed enhanced SO2 tolerance. Compared with the commercial Cu-SSZ-13 catalyst, the ternary MnCoVOx catalysts showed comparable activity but better sulfur resistance. Thereby, the easy-synthesized and low-cost ternary metal oxides based on the dinuclear active sites tuning strategy pave a way for designing superior denitration catalysts for practical applications.

Effect of Bimetal Element Doping on the Low-Temperature Activity of Manganese-Based Catalysts for NH3-SCR.

A series of novel Mn6Zr1-xCox denitrification catalysts were prepared by the co-precipitation method. The effect of co-modification of MnOx catalyst by zirconium and cobalt on the performance of NH3-SCR was studied by doping transition metal cobalt into the Mn6Zr1 catalyst. The ternary oxide catalyst Mn6Zr0.3Co0.7 can reach about 90% of NOx conversion in a reaction temperature range of 100-275°C, and the best NOx conversion can reach up to 99%. In addition, the sulfur resistance and water resistance of the Mn6Zr0.3Co0.7 catalyst were also tested. When the concentration of SO2 is 200ppm, the NOx conversion of catalyst Mn6Zr0.3Co0.7 is still above 90%. 5 Vol% H2O has little effect on catalyst NOx conversion. The results showed that the Mn6Zr0.3Co0.7 catalyst has excellent resistance to sulfur and water. Meanwhile, the catalyst was systematically characterized. The results showed that the addition of zirconium and cobalt changes the surface morphology of the catalyst. The specific surface area, pore size, and volume of the catalyst were increased, and the reduction temperature of the catalyst was decreased. In conclusion, the doping of zirconium and cobalt successfully improves the NH3-SCR activity of the catalyst.

Ce(SO4)2/α-Fe2O3 selective catalytic reduction of NOx with NH3: preparation, characterization, and performance.

To achieve a low-cost, high-activity denitrification catalyst with excellent water and sulfur resistance, goethite and Ce(SO4)2·4H2O were used to prepare Ce(SO4)2/α-Fe2O3 composite catalyst by the impregnation way and investigated the effect of Ce(SO4)2 on the properties of goethite. Ce(SO4)2/α-Fe2O3 with various preparation conditions for denitration was systematically discussed, and its structure and properties were characterized by XRD, BET, TEM, XPS, H2-TPR, and NH3-TPD methods. The results showed that Ce(SO4)2/α-Fe2O3 over the Ce/Fe molar ratio of 0.02 and calcination temperature of 350 ℃ had excellent catalytic activity, resistance to sulfur, and water properties and stability. When NOx initial concentration was 500ppm, gas hourly space velocity was 36,000h-1 and its reaction temperature was 300 ℃; the NOx conversion efficiency was maintained at over 95% along with 300ppm SO2 and nearly 100% couple with 10% H2O. Its superior performance was mainly attributed to the enhancement of the surface adsorbed oxygen and acidity of α-Fe2O3 by cerium sulfate. The multiple advantages of Ce0.02/α-Fe2O3(350) made it feasible for practical engineering application.

Kinetics Analysis of the NH3-SCR Denitration Reaction over Sintered Ore Catalysts

Utilizing sintered ore catalysts (SOC), which are used in the sintering industry for NH3-SCR denitration, is a feasible and economical way to reduce NOx emission in sintering flue gas. Therefore, in order to enhance the denitration efficiency of SOC, sintered ore modified by sulfuric acid and sulfated sintered ore catalysts (SSOC-5) were prepared. Kinetic analyses of these two catalysts for denitration were carried out in this study. On the basis of eliminating the influence of internal and external diffusion, the relationship between reactants and reaction rate was studied by a power function kinetic model. This clarified that the adsorption ability of the acid-modified catalyst for reaction gas adsorption was stronger than that of sintered ore catalysts, and the reaction rate was also accelerated. The NO, NH3 and O2 reaction orders of SOC were 1, 0.3 and 0.16 at 250~300 °C, while these values of SSOC-5 were 0.8, 0.06 and 0.09, respectively. The apparent activation energy of SOC was 83.66 kJ/mol, while the value of SSOC-5 decreased to 59.93 kJ/mol.

In-situ infrared spectroscopic study of the mechanism of the low temperature selective catalytic reduction of NO surface by Mn/ bastnaesite concentrate

The Mn/bastnaesite concentrate and Mn/Al2O3 catalysts were prepared by impregnation method, and their NH3-SCR denitrification performance was tested. The results showed that the Mn/bastnaesite concentrate catalyst achieved up to 95% NO conversion rate at 150 °C, and the Mn/Al2O3 catalyst reached 76% at 300 °C. A series of characterisation results showed that the bastnaesite concentrate can better interact with MnOx species and promote mutual dispersion compared to Al2O3. The Mn/bastnaesite concentrate has a stronger redox capacity, and good NH3 and NO adsorption capacity at low temperatures. The multi-element coexistence system of bastnaesite concentrate itself is a significant advantage of its use as a carrier. In-situ Fourier transform infrared (FTIR) results showed that the Mn/bastnaesite concentrate catalyst follows an L-H mechanism throughout the reaction, with NH4+ species in the Brønsted acidic site on the catalyst surface being the main reactant species. Most of NO is converted to monodentate nitrite, which is formed by bonding with Mn3+ provided by the supported Mn species, rare earth elements and transition metal ions contained in the carrier itself to form O–N–O–Mn3+ intermediates, which participate in the reaction together, and then combined with the adsorbed NH4+/NH3 species to produce N2 and H2O. An E-R mechanism was also present on the catalyst surface, NO participates directly in the reaction in gaseous form, and the NO [NH2](ads) intermediate species produced by interaction with NH4+ species in the acidic position of Brønsted was further decomposed to N2 and H2O. By comparing the reaction mechanism with the commonly used catalyst carrier Al2O3 for NH3-SCR, it can be concluded that bastnaesite concentrate as a carrier not only has the performance of conventional carriers, but also has certain catalytic activity and can interact with the active components to give it excellent performance, which provides a theoretical basis for rare earth minerals as denitrification catalysts.