Study on catalytic reforming of volatile-N from pyrolysis of Shengli brown coal by activated chars

In order to decrease the release of harmful nitrogen (including HCN, NH3 and tar-N) during the pyrolysis of brown coal, taking chars that prepared with bi omass, brown coal, bituminous coal and anthracite and chars with loading mass fraction 7%，10%， 13% and15% Ca2+ as catalysts, the catalytic reforming of volatile-N fr om pyrolysis of Shengli brown coal was studied in a two-stage fluidized-bed quartz reactor. The results showed that activated char apparently contributed to the second ary reaction of tar and HCN, thus reducing the production rate of tar-N and HCN as well as increasing the yield of N2.Ca2+loaded in char was beneficial to release hydr ogen radicals and further catalyze tar-N cracking. Overall, the char catalyst derived from bituminous coal had the better catalytic activity than the chars from other mate rials, whereas the loading level of Ca2+on char should be controlled at around 13% to achieve the best performance in this study.The major factors that affected char ac tivity were the specific surface area, the O-containing functional groups, alkali metals and hydrogen radicals.