Low-Temperature Selective Catalytic Reduction of NOx with Urea Supported on Carbon Xerogels

Insight into the mechanism of boron-doping of carbon aerogel for enhancing the activity of low-temperature selective catalytic reduction of NO with NH3

Boron doped carbon aerogel could increase the number of active sites effectively and enhance NO reduction to N₂via NH₃-SCR.

Synergistic effect of modified Pd-based cobalt chromite and manganese oxide system towards NO-CO redox detoxification reaction

Surface architecting of the catalyst is a hopeful method to expand the surface property of the impetus material for upgrading their response towards the chemical reaction. In the present study, designing of the catalyst was carried out using specific transition metals to boost the simultaneous NO-CO conversion reaction catalytically. These metal oxide systems have been prepared using the combustion and wet impregnation method. Prepared oxides were characterized using XRD, BET, XPS, SEM, and TEM. Further, the surface phenomenon of the catalyst was monitored through H₂-TPR, O₂-TPO, NO-TPD, and CO-TPD studies. The highly remarkable activity was perceived by Pd-based modified manganese oxide-cobalt chromite system as compared with simple Pd-based manganese oxide and Pd-based cobalt chromite. The catalyst showed the highest activity for NO-CO redox reaction with T₁₀₀ at 170 °C. Also, good stability was observed with a runtime of 7 h.

A Review of Urea Pyrolysis to Produce NH3 Used for NOx Removal

Urea pyrolysis, from which the denitration reactant ammonia is produced, plays an important role in the urea-based NOx removal process. Research into urea pyrolysis is mostly focused on three parts: urea pyrolysis pathway, catalytic hydrolysis of HNCO, and catalytic pyrolysis of aqueous urea solution. In this paper, detailed overview on research progress of urea pyrolysis was conducted. From the review, it could be concluded that although much research has been carried out, concentration was mainly in analysis of urea pyrolysis products and exploration of catalysts used to improve ammonia yields. Little work has been done on mechanism study and development of a kinetic model with high accuracy, which are still in great need nowadays.