Catalytic Gasification of Sewage Sludge in Supercritical Water: Influence of K2CO3 and H2O2 on Hydrogen Production and Phosphorus Yield

In this work, the catalytic gasification of sewage sludge in supercritical water was investigated in a batch reactor (460 °C, 27 MPa, 6 min), and the separate and combined effects of the catalyst on the H 2 production and phosphorus yield were investigated. The experimental results indicated that K 2 CO 3 alone improved the H 2 yield, gasification efficiency (GE), and carbon gasification efficiency (CE). The largest H 2 yield of 54.28 mol/kg was achieved, which was approximately three times that without a catalyst. Furthermore, the inorganic phosphorus (IP) yield increased with the addition of K 2 CO 3 . However, when H 2 O 2 was added, the H 2 yield quickly decreased with increasing H 2 O 2 coefficient, and more than 97.8% of organic phosphorus (OP) was converted into IP. The H 2 yield increased with the addition of various K 2 CO 3 /H 2 O 2 ratios, whereas the IP yield decreased.