Hydrothermal degradation of cellulose (DP~450) in 0.02-0.20moldm-3 aq. hydrochloric acid at 160°C, for 2-8h and neutralization of the filtrate with calcium hydroxide can be used to prepare a mixture of carboxylic acid calcium salts. The mixture consists of calcium levulinate and calcium formate in approximately 1:0.65mol ratio, together with CaCl2. Pyrolysis of this crude mixture at 350°C for 3.0min produces pyrolyzate oil yield of 140-210gkg-1 of dry salt mixture. The pyrolyzate was identified as ~97% γ-valerolactone, with the minor products; levulinic acid, 3-methyl-2-cyclopentenone, and 2,3-dimethyl-2-cyclopentenone by using a combination of GC-MS and NMR spectroscopy.