Unravelling the significance of catalyst reduction stage for high tar reforming activity in the presence of syngas impurities

Tar Formation in Gasification Systems: A Holistic Review of Remediation Approaches and Removal Methods

“…27,68,70,115,140−151 Catalytic tar cracking is considered to be promising, as it can be performed at temperatures close to that of gasifier outlet. 151 The expectations of a catalyst material for tar cracking are summarized as follows: 152 1. Good activity and efficiency in removing tar present in a gas mixture (producer gas) 2.…”

“…Tar reduction using a catalyst is another promising technique, which can be implemented in two ways: one way is integrating the catalyst with the input biomass to eliminate the tar within the gasifier itself (in situ approach), leading to what’s known as catalytic gasification or pyrolysis, and the second way is where tar is removed outside the gasifier in a secondary reactor packed with the catalyst. , Catalysts are effective in cracking tar compounds through reforming, cracking, hydrogenation, and selective oxidation, and many researchers have widely studied their performance over time. ,,,,− Catalytic tar cracking is considered to be promising, as it can be performed at temperatures close to that of gasifier outlet . The expectations of a catalyst material for tar cracking are summarized as follows: Good activity and efficiency in removing tar present in a gas mixture (producer gas) Good stability to deactivation and poisoning Easy regeneration Good abrasive strength Inexpensive and ready availability Less harm to the environment …”

“…58 , 139 Catalysts are effective in cracking tar compounds through reforming, cracking, hydrogenation, and selective oxidation, and many researchers have widely studied their performance over time. 27 , 68 , 70 , 115 , 140 − 151 Catalytic tar cracking is considered to be promising, as it can be performed at temperatures close to that of gasifier outlet. 151 The expectations of a catalyst material for tar cracking are summarized as follows: 152 Good activity and efficiency in removing tar present in a gas mixture (producer gas) Good stability to deactivation and poisoning Easy regeneration Good abrasive strength Inexpensive and ready availability Less harm to the environment …”

“…Based on the nature of impurities, such as halides, siloxanes, etc., sintering, deactivation, and blocking of active sites of catalysts can occur. Although Ni is preferred due to its low cost and wide availability, 151 Ni catalysts (prereduced) are known for being poisoned by sulfides, metal chlorides, and alkali oxides, with reports of rapid deactivation from sulfur and high tar contents due to chemisorption. This could necessitate pretreatment of feed gas, which is not fulfilling the objective of catalytic tar cracking.…”

Catalytic Activity and Coke Resistance of Gasification Slag-Supported Ni Catalysts during Steam Reforming of Plastic Pyrolysis Gas

“…The reactor was then fitted inside a furnace and connected to a water pump. The catalysts were not reduced prior to the reforming reactions as the activity of both calcined and reduced catalysts converges (unless there are impurities such as H 2 S) due to the formation of similar active sites. , Figure S1 shows the schematic diagram of the steam reforming system. For each run, the reaction conditions were identical: 800 °C, heating rate of 10 °C min –1 , flow rate of pyrolysis gas of 30 mL min –1 (space velocity of 60 mL min –1 g –1 ), and water flow rate of 0.2 g min –1 .…”