TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The inert particulate material is a deactivated particulate catalyst material and/or inert particulate solid heat carrier material. The inert particulate material is sand. The deactivated particulate catalyst material is entrained from the first stage reactor into the second stage reactor. The solid particles comprise deactivated catalyst particles. In the method (M1), the entrained fluidized bed comprises a deactivated particulate catalyst. The catalyst comprises a zeolite; ZSM-5, zeolite-Y, or modified forms of ZSM-5 and zeolite-Y, dealuminated zeolites, ultrastable zeolites, mordenites and/or mesoporous materials; sulfonated, phosphated, or fluorinated forms of zirconia, titania, alumina, silica-alumina and/or clays; solid base; oxide, hydroxide or carbonate of a metal; layered double hydroxide, mixed metal oxide, hydrotalcite, hydrotalcite-like material, clay, clay comprising alkaline earth or transition or rare earth metal oxide, hydroxide, carbonate and/or hydroxy carbonate; alumina, titania, or zirconia; calcined clay. The clay comprises kaolin. The catalyst has a specific surface area of 1-400 m2/g. Preferred Method: The first stage is carried out in a fluidized bed reactor where the fluidized bed reactor is circulating fluidized bed reactor, an ebullated bed reactor or an entrained fluid bed reactor. The first stage is carried out in an entrained fluidized bed. In the method (M1), the primary reaction products are entrained from the first zone of the reactor to the second zone of the reactor by a lift gas. The second stage involves: contacting the primary reaction products with a catalyst. The method (M1) further involves: separating deactivated catalyst particles from the secondary reaction products; removing volatile materials from the deactivated catalyst particles in a stripper; injecting at least part of the deactivated catalyst particles from the stripper into the first zone of the reactor; regenerating at least part of the deactivated catalyst particles in a regenerator; injecting regenerated catalyst particles from the regenerator into the second zone of the reactor; feeding solid particulate biomass material into the first zone of the reactor. The deactivated particles from the stripper are heated or cooled prior to injection into the first zone of the reactor. The regenerated catalyst particles are heated or cooled prior to injection into the second zone of the reactor. The solid particulate biomass material is heated or cooled prior to feeding into the first stage. The reactor temperature of the second stage reactor is higher than the reactor temperature of the first stage reactor. The reactor temperature of the first stage reactor is 350-600 (preferably 400-550) degrees C. The pyrolysis reaction is carried out in the substantial absence of a catalyst. When the method (M1) uses catalyst in the second stage, then the method (M1) involves: removing solid particles from the secondary reaction products, where the solid particles comprise deactivated catalyst particles. The method (M1) further involves: stripping volatile materials from the deactivated catalyst particles prior to regenerating; recycling catalyst particles back to the first zone, or the second zone, or both the first and second zones of the reactor; recycling at least a portion of the regenerated catalyst particles back to the reactor. At least a portion of the regenerated catalyst particles are recycled back to the second zone of the reactor. The reactor temperature in the second zone is higher than the reactor temperature in the first zone. The method (M1) further involves: recycling catalyst particles back to the lower zone, or the upper zone, or both the lower and upper zones of the reactor; stripping volatile materials from the deactivated catalyst particles; regenerating at least part of the deactivated catalyst particles from the stripper, forming regenerated catalyst particles; recycling regenerated catalyst particles back to the reactor. In the method (M1), the portion of the regenerated catalyst particles are recycled back to the upper zone of the reactor.    TECHNOLOGY FOCUS - INSTRUMENTATION AND TESTING - Preferred Reactor: The reactor is provided with a device for injecting a lift gas into the first stage reactor, which lift gas transports primary reaction products from the first stage reactor to the second stage reactor. The first stage reactor is a circulating fluidized bed reactor, ebullated bed reactor or entrained fluid bed reactor. The two-stage reactor comprises device for removing solid particles from the secondary reaction products; stripper for stripping volatile materials from the deactivated catalyst particles prior to regeneration in the regenerator; device for injecting at least part of the deactivated catalyst particles from the stripper into the first stage reactor; heat exchanger for heating or cooling the deactivated catalyst particles froth the stripper before injection into the first stage reactor; regenerator for regenerating at least part of the deactivated catalyst particles from the stripper forming regenerated catalyst particles; device for injecting regenerated catalyst particles from the regenerator into the second stage reactor; heat exchanger for heating or cooling regenerated catalyst particles from the regenerator before injection into the second stage reactor; feeder system for feeding solid particulate biomass material into the first stage reactor. The two-stage reactor further comprises device for recycling catalyst particles back to the first stage reactor, or the second stage reactor, or both the first and second stage reactors of the two-stage reactor; device for recycling at least a portion of the regenerated catalyst particles back to the two-stage reactor. Preferred Components: The first stage reactor and the second stage reactor each have an internal diameter, and where the internal diameter of the second stage reactor is less than the internal diameter of the first stage reactor. The first stage reactor contains an inert particulate material. The second stage reactor is an entrained fluid bed reactor. The second stage reactor is provided with a device for injecting a particulate solid catalyst. The first stage reactor has an internal diameter d1, the second stage reactor has an internal diameter d2, and the ratio d1:d2 is 1.3:1 to 15:1 (preferably 2:1 to 10:1, especially 3.5:1 to 7:1). The feeder system comprises a heat exchanger for heating or cooling the solid particulate biomass material prior to feeding into the first stage reactor. In the reactor, at least a portion of the regenerated catalyst particles are recycled back to the second stage reactor of the two-stage reactor. The device for recycling comprises device for injecting regenerated catalyst particles into the second stage reactor.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The catalyst comprises a solid acid or a super acid. EXAMPLE - No suitable example given.