Novel natural manganese ore NH₃‐SCR catalyst with superior alkaline resistance performance at a low temperature

Abstract

Potassium nitrate (KNO 3 ) was chosen as the precursor to prepare the K-poisoned catalysts on natural manganese ore using the impregnation method. The results demonstrate that the natural manganese ore catalyst possesses superior alkaline resistance performance with a high NO x conversion for NH 3 -SCR of NO x at a low temperature. There are two factors responsible for the alkaline resistance performance. Firstly, the NH 3 adsorption capacity (more acid sites) of K-poisoned catalysts is stronger than that of fresh catalyst, which is beneficial for the NO x conversion. Secondly, the K-poisoned catalyst has a smaller specific surface area, lower concentrations of Fe 3þ , Mn 4þ , and O a , and lower reducibility, which leads to an inhibition effect on the NO x conversion. There exists a competition mechanism between the promotional and inhibition effect on the NO x conversion. The combination of these two effects leads to natural manganese ore exhibiting a superior alkaline resistance performance.

Vanadium-bearing steel slag catalysts for the selective catalytic reduction of NOx by NH3

“…Its main components include iron and vanadium. 14–16 Some researchers have prepared good denitration catalysts using natural minerals as raw materials, such as iron ore, 17–19 manganese ore 20–22 and blast furnace slag. 23–26 These studies show that vanadium-bearing steel slag has great potential as a denitration catalyst.…”