The catalyst recovery process was investigated utilizing different washing methods and operating conditions after potassium-catalyzed steam gasification. During potassium-catalyzed steam gasification, the H-2 yield and carbon conversion (X-C) could reach 101.18 g/kg-coal and 73.39%, respectively, when utilizing Lanna clean coal as a sample; the potassium compounds mainly existed in three forms: KAlSiO4, KHCO3, and K2SO4. In the catalyst recovery process, the highest recovery efficiency of potassium (eta(K)) on Lanna raw coal and clean coal gasified residue reached 92.14% after six limewater washings and 93.37% after three limewater washings, respectively. When utilizing the combined washing method for the Lanna clean coal gasified residue, the recovered catalyst showed a longer catalyst reuse lifetime even though the recovery efficiency of potassium (eta(K)) only reached 89.42%, which was 4% lower than that obtained after three limewater washings. (C) 2015 Elsevier B.V. All rights reserved.