###### Abstract  
Supercritical CO\({}_{2}\) (SuCO\({}_{2}\)) dewatering can mitigate capillary tension and reduce wood collapse. In this study, _Eucalyptus urophyulla \(\times\) E. grandis_ specimens were dewatered by SuCO\({}_{2}\) at temperatures of 35, 40 and 55 \({}^{\circ}\)C, in pressures of 10 and 30 MPa, respectively, for 1h. Effects of temperature and pressure on dewatering rate, moisture content (MC) distribution and gradient, shrinkage and residual stress of wood after dewatering were investigated. The results indicate that the SuCO\({}_{2}\) dewatering rate is much faster than that of conventional kiln drying (CKD). The dewatering rate increases with increasing of temperature and pressure; however, pressure has a significant influence, especially for the high-temperature dewatering process; the MC distribution after 1h dewatering is uneven and MC gradients decrease with reducing of mean final MC of wood. MC gradients along radial direction are much smaller than that in tangential direction; collapse of wood significantly reduces after dewatering due to SuCO\({}_{2}\) decreasing the capillary tension, and residual stress of wood during dewatering is mainly caused by pressure of SuCO\({}_{2}\), which decreases with increasing temperature. SuCO\({}_{2}\) dewatering has great potential advantages in water-removal of wood prone to collapse or deformation.  
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drying. On the other hand, collapse and internal checks may be mitigated using special approaches, such as freeze-drying [22] or supercritical CO\({}_{2}\) (SuCO\({}_{2}\)) dewatering [23], which may remove or eliminate the capillary tension during free water migration.  
As is known, SuCO\({}_{2}\) fluid is an excellent transfer medium, which has wonderful properties, such as excellent solubility and heat transfer, non-toxicity, non-flammability, high recovery rate and strong process selectivity medium. As a green wood processing medium, SuCO\({}_{2}\) has been used successfully in wood industries, such as wood preservation, dying, extraction and thermochemical conversion due to its advantages of efficiency and environmental friendliness [24; 25; 26]. Conventional kiln drying (CKD) are widely used in the world, but resulting in excessive greenhouse gas and primary organic aerosols emissions for burning fossil fuel to obtain heat and steam [27], recently, dewatering wood using clean SuCO\({}_{2}\) fluid has been reported [28]. The water-removing mechanism of SuCO\({}_{2}\) fluid is attributed to the pressure difference between the CO\({}_{2}\) of the supercritical phase and the gas phase. Dewatering wood using SuCO\({}_{2}\) fluid differs from water evaporation in CKD of wood and may eliminate negative water tension maximally. Few collapses and cracks in wood were found after dewatering using SuCO\({}_{2}\)[29; 30; 31]. Thus, this dewatering method has great potential in such timbers as eucalyptus and poplar prone to collapse. There were some studies [32; 33; 34] investigating wood dewatering using SuCO\({}_{2}\), but few investigations were related to the refractory eucalyptus wood and the effect of SuCO\({}_{2}\) on shrinkage and drying stress [35; 36].  
In the present paper, _Eucalyptus urophylla \(\times\) E. grandis_ wood was dewatered using SuCO\({}_{2}\), at 35, 40 and 55 \({}^{\circ}\)C, in 10 and 30 MPa, respectively, for 1 h. The focus is, in particular, the systematical investigation into the interrelationship among temperature and pressure of SuCO\({}_{2}\) and dewatering rate, moisture distribution, drying stress and shrinkage during dewatering, will provide theoretical and practical support for improving the yield of eucalyptus timber manufacturing.