A treatment process for producing implants or prostheses of polymers for controlled release of active ingredients, characterized by a first "pretreatment" step comprising: - a phase of pressurization and heating according to controlled kinetics, - a phase of bringing the polymeric materials into contact with a supercritical fluid in batchwise mode or in continuous mode, and - a phase of depressurization with controlled kinetics, under isothermal conditions.

The present study deals with the determination of optimal values of operating parameters such as temperature and pressure leading to the best yield of a supercritical CO2 extraction of essential oil from local rosemary plants, using the response surface methodology (RSM). The maximum of essential oil recovery percentage relative to the initial mass of leaf powder was 3.52 wt%, and was obtained at 313 K and 22 MPa. A second-order polynomial was used to express the oil recovery and the calculated mass of recovered oil using the RSM was very close to the experimental value, confirming the reliability of this technique. The chemical composition of the Algerian rosemary oil under the obtained optimal conditions (313 K and 22 MPa), determined by GC-MS analysis, revealed the presence of camphor (major compound) (52.12%), 1,8-cineole (9.65%), camphene (7.55%), alpha-pinene (6.05%), borneol (3.52%), aroma dendrene (2.11%), verbenone (1.97%), alpha-caryophyllene (1.71%), and others. (C) 2016 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.

Many recrystallization processes in supercritical medium utilize CO(2) as antisolvent. This work presents two introduction devices based on the principle of the supercritical antisolvent process: the impinging jets and the concentric tube antisolvent reactor. Those two processes are very simple to develop and allow improving the mixing between the two phases. Some experiments have been conducted for the impinging jets using L-polylactic acid at 10 MPa and 308 K giving spherical particles with average diameter varying from 1.4 to 2.3 mu m. For the concentric tube antisolvent reactor, griseofulvin was tested at 10 MPa and temperatures between 308 and 323 K providing needles with lengths between 25 and 50 mu m. These results combined with previous ones allow comparing these introduction devices with the classical supercritical antisolvent (SAS) process, demonstrating the following improvements: (i) reduction of particle size, (ii) increase in initial solute concentration, and (iii) process intensification.

To evaluate the potential recovery rate of volatile terpenes from pulp mills, different extraction methods were performed on fir, spruce and maritime pine, and the extracts were analyzed by gas chromatography-flame ionization detector/mass spectroscopy (GC-FID/MS). The results obtained by traditional solvent extraction in the Soxhlet and the accelerated solvent extraction (ASE)(R) apparatus were compared with those of steam distillation technology (Clevenger), and supercritical CO2 (SC-CO2) extraction was also tested as an interesting alternative to extraction with liquid organic solvents. ASE (R)-Dionex applied on freeze-dried samples with successive extraction with n-hexane and acetone/water (95/5) was not suitable for volatile compounds. Steam distillation applied on fresh and ground samples was very specific of volatiles, but did not allow complete extraction. Soxhlet extraction performed on fresh and ground samples with successive application of acetone and acetone/cyclohexane (1/9) gave the most representative quantification of ground wood chips, together for volatile terpenes, resins and fatty-acidtype compounds. SC-CO2 [20 and 30 MPa, 60 degrees C modified by 5% ethanol (EtOH)] is able to extract most of the terpenes, terpenoids and fatty-acid-type compounds, but the extraction rates of volatiles were very limited because of a pre-drying step (freeze-drying and crushing). Other lipophilic extractives were also recovered to a lesser extent.