Catalytic Oxidation of NO Over Activated Semi-Cokes by Different Preparation Methods
The objective of this research is to use semi-cokes the raw material to prepare catalysts of NOX removal by Selective catalytic oxidation (SCO). Based on previous studies, the combination methods involved hydrothermal activation (P), nitric acid (N), alkali activation (SH) and calcining activation(HT) were adopted to increase the activity .The prepared catalyst was tested in the fixed bed reactor (Ø14mm×280mm) under the condition of atmosphere: the temperature 70ºC, space velocity 600h-1, the concentrations of O2 and NO being 5% and 320ml/m3 respectively. The article assumed that less than 60% of the conversion rate of NO was the breakthrough point, when the point was termed as TB. The BET, SEM, acid-base titration, Boehm’s titration and proximate analysis were adopted in this article. The results showed that the TB was relative to the contents of basic function and carbonyl groups when the ash of activated semi-coke was under 8%. The carbonyl groups controlled the first step of SCO and the BFG controlled the migration and storage of the products to concede the active site. The combination method of N-SH-HT gained the best effect of TB,48.5 hours. The nitric acid activation could get great effort to decease the content of ash; alkali activation could increase the basic groups and calcining activation increase the contents of carbonyl group. The products of the SCO contained on the semi-cokes as nitrate.