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Patchouli extracts and oils extracted from Pogostemon cablin are essential raw material for the perfume and cosmetics industries, in addition to being used as a natural additive for food flavoring. Steam distillation is a standard method used for plant extraction. However, this method causes thermal degradation of some essential components of the oil. In this study, patchouli was extracted with supercritical carbon dioxide (SC-CO2) under different conditions of pressure (10–30 MPa) and temperature (40–80 °C). The chemical components of the crude extracted oil and the functional group were characterized using gas chromatography-mass spectrometry (GC-MS) and Fourier Transform Infrared Spectroscopy (FT-IR). The extraction with supercritical carbon dioxide was shown to provide a higher yield (12.41%) at a pressure of 20 MPa and a temperature of 80 °C. Patchouli alcohol, Azulene, δ-Guaiene, and Seychellene are the main bioactive compounds that GC-MS results have identified. FTIR spectra showed alcohol, aldehyde, and aromatic ring bond stretching peaks. Extraction of patchouli with supercritical carbon dioxide provided a higher yield and a better quality of the crude patchouli oil.

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The increasing emission of carbon dioxide to the atmosphere from various sources has become an issue of great concern all over the world due to its significant contribution to climate change. Carbon capture and storage are commonly recognized as the major approaches to prevent carbon dioxide from entering the atmosphere. A number of CO2 removal technologies have been reported, including absorption, adsorption, membrane separation, and microalgal fixation. In this study, a Computational Fluid Dynamics (CFD) study was performed to investigate the performance of two adsorbents, coconut fiber activated carbon and zeolite 13X in removing CO2 from a continuous gas stream in a fixed bed adsorption column. A CFD code ANSYS R18.2 was used to investigate the influence of flow rate and bed height on the CO2 removal efficiency and adsorption capacity by varying the inlet feed velocity and bed heights. The results of the simulation showed that the highest CO2 removal efficiency of 63.13 percent was observed when the gas flowed at a rate of 50 cm3/minute to the column filled with the activated carbon adsorbent of 10 cm in height. While in the zeolite adsorbent 13X, the highest CO2 removal efficiency of 57.86 percent was also seen when the gas flowed at a rate of 50 cm3/minute at the bed height of 10 cm.

Published paperPresented are results obtained from the incorporation of a semi-empirical soot model into a first-order conditional moment closure (CMC) approach to modelling turbulent, non-premixed methane-and propane-air flames. Soot formation is determined via the solution of two transport equations for soot mass fraction and particle number density, with acetylene and benzene employed as the incipient species responsible for soot nucleation, and the concentrations of these calculated using a detailed gas-phase kinetic scheme involving 70 species. The study focuses on the influence of differential diffusion of soot particles on soot volume fraction predictions. The results of calculations are compared with experimental data for atmospheric and 3 atmosphere methane flames, and propane flames with air preheated to 323 K and 773 K. Overall, the study demonstrates that the model, when used in conjunction with a representation of differential diffusion effects, is capable of accurately predicting soot formation in the turbulent non-premixed flames considered.