TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The step of accelerating the motive fluid to at least Mach 1 comprises moving the motive fluid through a constricted passage in the reactor. The step of reacting the feedstock with the high speed motive fluid produces an effluent material, and the method comprises reacting the effluent material in a tubular reactor. The method comprises: hydrolyzing the lipid material and producing free fatty acids, where the feedstock includes the free fatty acids; and recycling a heavy fraction of an effluent material from the reactor back through the reactor. The step of hydrolyzing the lipid material produces glycerol, where the method comprises reacting the glycerol and producing alkyl-aromatics. The motive fluid moves: through a constricted passage in the first reactor to accelerate the motive fluid; or constricted passage in the nozzle reactor to accelerate the motive fluid to at least Mach 1. The method-I comprises: accelerating the motive fluid in the first reactor to at least Mach 1; and recycling a heavy fraction of the second effluent material back through the first reactor and the second reactor. The tubular reactor outputs a second effluent material, and the method comprises separating a heavy fraction from the second effluent material and recycling it back through the nozzle reactor and the tubular reactor. The tubular reactor has a residence time of 0.05-1.5 seconds. In the method, at least 70% of the lipid material reacts and forms fatty acid esters, fatty alcohols, and/or paraffinic and branched hydrocarbons. Preferred Components: The effluent material from the reactor includes: mono-alkyl esters of fatty acids and/or fatty alcohols; and paraffinic and branched hydrocarbons. The second effluent material includes mono-alkyl esters of fatty acids, fatty alcohols, and/or paraffinic and branched hydrocarbons. The reactor is a nozzle reactor. The feedstock includes: at least 20 wt.% of fatty acid material; and alcohol. The motive fluid includes steam and/or natural gas. The feedstock is deoxygenated, isomerized, and/or cracked in the reactor. The first reactor includes a nozzle reactor. The second reactor includes a coil reactor. EXAMPLE - None given.