CO2 Flow Rate Research Articles

Antioxidant Activity and Total Polyphenols Content of Camellia Oil Extracted by Optimized Supercritical Carbon Dioxide

AbstractIn this study, Camellia oil is co‐extracted from Camellia oleifera seeds and green tea scraps by supercritical carbon dioxide (SC‐CO2), which is optimized on the extraction yield, ABTS‐scavenging activity, and total polyphenols content (TPC) of oil by single‐factor experiments combined with response surface methodology (RSM). The extraction temperature, pressure, dynamic time, carbon dioxide (CO2) flow rate, and seed mass ratio were investigated with single‐factor experiments. The results indicated the optimum CO2 flow rate and dynamic extraction time were 15 L hour−1 and 60 min (i.e., 2.382 kg CO2/100 g sample). Furthermore, the complicated effects of extraction temperature (40–50 °C), pressure (20–30 MPa), and seed mass ratio (0.25–0.75) were optimized by RSM based on the Box–Behnken design (BBD). The models with high R‐squared values were obtained and used to predict the optimum operating conditions of the process. Under the optimum operating conditions (i.e., temperature of 46 °C, pressure of 30 MPa, and seed mass ratio of 0.35), the extraction yield, ABTS‐scavenging activity, and TPC of oil were 14.43 ± 0.17 g/100 g sample, 73.70 ± 0.34%, and 2.18 ± 0.05 mg GAE/g oil, which were in good agreement with the predicted values. In addition, the experiments indicated that the Camellia oil obtained was rich in polyphenols, resulting in better oxidation stability and antioxidant activity than the original oil.

Supercritical carbon dioxide extraction of α-mangostin from mangosteen pericarp with virgin coconut oil as co-extractant and in-vitro bio-accessibility measurement

Abstract This work aims to develop a method for producing α-mangostin that has high bio-accessibility through the use of supercritical carbon dioxide (scCO2) extraction of mangosteen pericarp extract (MPE) with virgin coconut oil (VCO) as co-extractant. Extractions with scCO2 were carried out at 30 MPa to 40 MPa, 60 °C, CO2 flow rate of 1.7 g/min and co-extractant VCO (0% to 20%). MPE yield and extraction yield increased with the amount of co-extractant added. The highest yield of MPE obtained was 17% at conditions of 35 MPa with 20% of VCO. The scCO2 MPE had higher bio-accessibility for α-mangostin (91%) than α-mangostin obtained by extraction with ethanol (30%) or hexane (50%). Thus, supercritical CO2 extraction used with virgin coconut oil co-extractant provides a method for producing high bio-accessible α-mangostin from mangosteen pericarp extract.

An Oxyfuel Combustion-Based Torrefaction Process: Technoeconomic Analysis

Abstract A torrefaction process operating on oxyfuel combustion concept is introduced. The working fluid employed in the process is carbon dioxide captured from the combustion products. The thermodynamic modeling of the process is carried out to determine the energy requirement, recycled CO2 flow rate, energy yield, and CO2 production rate at various torrefaction conditions. The total capital investment and production costs of the new system are also estimated. By increasing the torrefaction severity, the CO2 production rate, recycled gas mass, and the process thermal energy requirement increase, whereas the grinding energy and the energy yield decrease. A comparison made between the performance and economic parameters of the new and a conventional torrefaction processes shows that the proposed process is expected to produce torrefied wood pellet of compatible fuel quality and overall efficiency while eliminating CO2 and NOx emissions at the expense of 11.5% and 9% increase in the capital and production costs, respectively. The proposed torrefaction process requires 91.8 M$ capital investment and 113.2 $ to produce 1 ton of torrefied wood pellets with 91% energy yield and 88% overall plant efficiency. Sensitivity analysis shows that the reactor type and raw biomass costs have significant impact on cost structures.

Nano Calcium Carbonate Production Utilizing Solvay-Process Industrial Wastewater and Carbon Dioxide

nanoparticles are catching more attention due to their implementation as a filling material in a variety of fields. Nowadays, calcium carbonate nanoparticles have a large number of industrial applications replacing more expensive binders. Global warming and climate change, which are mainly caused by the increased concentration of carbon dioxide gas (CO2), turned to be a significant problem for our society. This research aims to develop an economic mineral carbonation process for the manufacture of nanoprecipitated calcium carbonate (NPCC), which can be considered also as an efficient way for the sequestration of CO2. The proposed research was divided into two stages, during the first stage a pure calcium chloride solution was carbonated, and the effect of different parameters (CO2 flow rate, ammonia amount, presence of additives, stirring rate, and ultrasonic waves) on the yield and the particle size of the produced particles was discussed. Then a synthetic Solvay wastewater sample was prepared and carbonated to study the effect of the presence of impurities on the particle size. The experimental results showed that increasing the amount of ammonia or the gas flow rate can affect the yield of the product while, increasing the stirring rate, the ammonia amount, or a suitable additive like glycerol have the effect to decrease the particle size. In the second stage, a process for ammonia recovery was modeled using Aspen Plus software v8.8 in order to make our process more economic.

Dynamic transport and reaction behaviour of high-pressure gases in high-rank coal

This paper presents the results obtained through continuous and simultaneous measurements of gas flow, temperature and coal deformation during high-pressure gas injection in high-rank coal samples, obtained from the South Wales coalfield (UK). The results demonstrate that CO2 flow rates experience an initial decline due to internal coal swelling, followed by the flow rate recovery and global coal swelling. As the flow of high-pressure CO2 induces measurable temperature drop within the sample related to the Joule-Thomson cooling, the changes induced by the variations in thermal state of the system are associated with abrupt shift in coal response to reactive gas flow. However, subsequent injections of He and N2 show that the changes induced by CO2 sorption on coal permeability to gases are irreversible. This work demonstrates the importance of considering the coupled reactive gas and heat transport, and consequent coal deformation mechanisms while assessing the storage potential of coal seams.

A simple novel route for porous carbon production from waste tyre.

In this research, waste tyre rubber was used for activated carbon production with a novel route by modified physo-chemical approach. Potassium hydroxide and carbon dioxide were selected as chemical and physical activating agents, respectively and the process was carried out without carbonization under inert atmospheric conditions. The experiments were designed by applying the central composite design (CCD) as one of the subsets of response surface methodology (RSM). The effects of activation temperature (550-750 °C), activation time (15-75 min), impregnation ratio of KOH/rubber (0.75-3.75) and CO2 flow rate (200-400 mL/min) on production yield and specific surface area of produced activated carbon were studied. Based on the results, the 2FI and quadratic models were selected for production yield and specific surface area, respectively. The activation temperature was the main effective parameter on both responses in this process. The production yield and specific surface area of produced activated carbon at optimized conditions for each model were 47% and 928 m2/g, respectively. BET, XRF, XRD, FT-IR, EDS and FE-SEM analyses were carried out on the optimized sample of specific surface area model in order to investigate the residual salts and morphological porous structures. Based on the surface properties and the presence of sulfur compounds in produced activated carbon, this activated carbon has the ability of eliminating heavy metals such as mercury from industrial waste water.

A novel carbon monoxide fed moving bed biofilm reactor for sulfate rich wastewater treatment

In this study, a moving bed biofilm reactor was used for biodesulfuruization using CO as the sole carbon substrate. The effect of hydraulic retention time (HRT), sulfate loading rate and CO loading rate on sulfate and CO removal was examined. At 72, 48 and 24 h HRT, the sulfate removal was 93.5%, 91.9% and 80.1%, respectively. An increase in the sulfate loading reduced the sulfate reduction efficiency, which, however, was improved by increasing the CO flow rate into the MBBR. Best results in terms of sulfate reduction (>80%) were obtained for low inlet sulfate and high CO loading conditions. The CO utilization was very high at 85% throughout the study, except during the last phase of the continuous bioreactor operation it was around 70%. An artificial neural network based model was successfully developed and optimized to accurately predict the bioreactor performance in terms of both sulfate reduction and CO utilization. Overall, this study showed an excellent potential of the moving bed biofilm bioreactor for efficient sulfate reduction even under high loading conditions.

Simulating and Quantifying Multiple Natural Subsea CO2 Seeps at Panarea Island (Aeolian Islands, Italy) as a Proxy for Potential Leakage from Subseabed Carbon Storage Sites

Carbon dioxide (CO2) capture and storage (CCS) has been discussed as a potentially significant mitigation option for the ongoing climate warming. Natural CO2 release sites serve as natural laboratories to study subsea CO2 leakage in order to identify suitable analytical methods and numerical models to develop best-practice procedures for the monitoring of subseabed storage sites. We present a new model of bubble (plume) dynamics, advection-dispersion of dissolved CO2, and carbonate chemistry. The focus is on a medium-sized CO2 release from 294 identified small point sources around Panarea Island (South-East Tyrrhenian Sea, Aeolian Islands, Italy) in water depths of about 40-50 m. This study evaluates how multiple CO2 seep sites generate a temporally variable plume of dissolved CO2. The model also allows the overall flow rate of CO2 to be estimated based on field measurements of pH. Simulations indicate a release of ∼6900 t y-1 of CO2 for the investigated area and highlight an important role of seeps located at >20 m water depth in the carbon budget of the Panarea offshore gas release system. This new transport-reaction model provides a framework for understanding potential future leaks from CO2 storage sites.

Co-gasification characteristics of waste tire and pine bark mixtures in CO2 atmosphere

Co-gasification of waste tire and pine bark in CO2 atmosphere is reported at different blend fractions of waste tire (WT) and pine bark (PB) in the range of WT:PB = 0:1, 1:0, 1:1, 1:3, and 3:1 with a focus on syngas production. The results are reported along with the thermal decomposition behavior of the blends investigated using thermogravimetric analyzer (TGA) in Ar atmosphere. Characteristics of syngas from the gasification of blends were conducted using a fixed-bed reactor in CO2 atmosphere at 800 and 900 °C. Gasification behavior was examined with focus on evolved flow rate of H2, CO, total hydrocarbons (CmHn), and total syngas yield at the two temperatures for different blend ratios. CO2 consumption under the gasification conditions was evaluated. Gas yield efficiency and energy recovered in gasification were also calculated and compared. Synergistic effects in the syngas yield and the role of waste tire and pine bark were analyzed by a direct comparison of the results on experimental yields from WT-PB blends as compared to the correspondingly calculated aggregate results from the gasification of separate feedstock components at 800 °C and 900 °C. Results showed that increase in pine bark ratio increased peak flow-rate of H2, CO, total syngas, but decreased peak flow-rate of CmHn at the two temperatures. The syngas yield of gases at 900 °C were higher than that at 800 °C for a given blend ratio. The peak value of temporal CO2 consumption coincided with the peaks of CO yield for all the feedstocks except for pure waste tire at 800 °C and 900 °C. Gas yield efficiency of gasification at 800 °C reduced using blends, while no obvious influence was found at 900 °C. Increase in pine bark decreased the energy output both at 800 °C and 900 °C. These results provide an insight into energy recovery and waste treatment potential for both waste tire and forestry waste as well as CO2 utilization in the thermochemical conversion.

Development of generalized and simplified models for supercritical fluid extraction: Case study of papaya (Carica papaya) seed oil

The present study described the experimentation and modeling of supercritical CO2 extraction (SCE) process for papaya seed oil. Experiments were performed at various ranges of SCE parameters; temperature (303.15–368.15)K, pressure (15–35)MPa, solvent flow rate (5–25)g/min, particle size (0.2–1.4)mm and co-solvent (ethanol) flow rate as (0–20)% of CO2 flow rate. Obtained oil was analyzed through gas chromatography to estimate fatty acid concentrations. Effects of SCE parameters were investigated on the extraction yield and oleic acid concentration of papaya seed oil through central composite design. Further, two mathematical models (PM-1 and PM-2) were developed based on desorption–diffusion–dissolution (PM-1) and broken and intact cell (PM-2) mechanisms. These models were validated with the experimental data of papaya seed oil and further compared with the existing models. PM-1 proposed an equilibrium relation while assuming saturation of solvent and solute at interphase, which was successfully validated with the experimental data in the AARD range from 0.40% to 32.48%. PM-2 reduced the three zones of extraction curves to two and better fitted the experimental data of papaya seed in the AARD range from 0.45% to 35.62%. Model parameters of PM-2 were optimized through genetic algorithm.

Optimization of activated palm oil sludge biochar preparation for sulphur dioxide adsorption

Palm oil sludge (POS) is an organic waste generated from the palm oil industry. POS causes environmental pollution if it is improperly disposed. In this study, the potential of activated POS biochar, as an adsorbent for the removal of SO2 gas was tested. POS biochar was physically activated using CO2 gas. The effects of activation preparation variables i.e. activation temperature (300–700 °C), activation time (30–150 min) and CO2 flow rate (100–500 ml/min) were investigated using design expert version 8.0.7.1 software. Central Composite Design (CCD) was used to develop a quadratic model to correlate the operating variables with the activated biochar adsorption capacity. Analysis of variance (ANOVA) was performed to identify the significant factors on the experimental design response. The optimum preparation conditions of activated POS biochar were found to be at activation temperature of 442 °C, activation time of 63 min and CO2 flow rate of 397 ml/min. The maximum adsorption capacity at the optimum conditions was recorded as 16.65 mg/g. The adsorption capacity increased significantly after the activation process. Characteristics of the activated POS biochar proposed that SO2 was physically adsorbed. Furthermore, it was found that the adsorption capacity can be further enhanced by increasing the reaction temperature to 100 °C or with 15% of relative humidity in the inlet gas. The prepared adsorbents can be regenerated by thermal treatment.

Fractionation of sterols, tocols and squalene in flaxseed oils under the impact of variable conditions of supercritical CO2 extraction

This study analysed the impact of selected adjustable parameters in the SFE such as SC−CO2 flow rate (6–12 mL/min), temperature (40–80 °C) and extraction time (2–6 h) on the oil recovery and content and composition of tocols, sterols and squalene in flaxseed oils. To track changes in the content of individual compounds in the oil, the Box-Behnken design with RSM was employed. It was found, that the oil yield was positively correlated with the ratio of SC−CO2 to sample mass and was only slightly modified by extraction temperature variation. A low SC−CO2 flow rate and short extraction time favoured the accumulation in oil of larger amounts of β/γ-tocopherols, squalene, stigmasterol and campesterol. In turn, a high SC−CO2 flow rate and long extraction resulted in the highest concentration in oil of plastochromanol-8, 25-hydroxy-24-methylcholesterol and 24-methylenecycloartanol. The concentration of β-sitosterol and cyclolanost-23-ene-3,25-diol was the highest after extraction at the highest temperature by medium extraction time.

Optimization of the self-condensing CO2 transcritical power cycle using solar thermal energy

Compared with the conventional Rankine cycle, the CO2 transcritical power cycle gives a higher thermal efficiency because of its high average heat absorbing temperature and is suitable for driving a compact system. The self-condensing CO2 transcritical power cycle can solve the problem that CO2 is difficult to condense in a conventional CO2 transcritical power cycle using conventional water cooling. Based on solar thermal energy, a theoretical analysis model was established to study the relationship between the cycle performance and the operating parameters. The results showed that the thermal efficiency increases with increasing the cooled pressure with a low final cooled temperature. By increasing the final cooled temperature, a peak appears on the thermal efficiency curve. The outlet temperature of the cooling water is affected by a shift of the pinch point position in the cooler. According to the variation of the outlet temperature of the cooling water and the proportion of the mass flow rate of CO2 in the power sub-cycle and that in the whole cycle, it can be concluded that conditions with a very low cooled pressure are uncontrollable. In these conditions, the maximum thermal efficiency of the self-condensing CO2 transcritical cycle is 0.3463, which is 0.0313 a little lower than that of the supercritical CO2 Brayton cycle. However, the novel cycle simplifies the development of the pressurizing component and avoids the liquid hammer in the pressurizing process.

Supercritical CO2 extraction and solvent-free rapid alternative bioepoxy production from spent hens

Spent hens are by-product of egg and hatching egg production and a potential source of renewable compounds. In this study, lipids were extracted using supercritical carbon dioxide (SC−CO2) at 50 − 70 °C, 30 − 50 MPa, and constant CO2 flow rate of 1 L/min. The maximum yield of total lipid 37 ±0.4 % (w/w) with 91.4% recovery was obtained at 50 MPa/70 °C. Fatty acid compositional analysis was performed using gas chromatography with flame ionization detector (GC-FID). Helium ion microscopy (HIM) was used to assess the morphological changes before and after extraction. Furthermore, epoxidation of the extracted lipids was conducted with and without the use of a solvent, where the solvent-free epoxidation was completed within 20 min and the yield was comparable. The reaction progress was monitored by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopy analysis, which showed the conversion rates of 59.8, 84.2 and 100% at 5, 10, and 20 min, respectively. The findings suggest that an alternative bio-epoxy can be produced using SC−CO2 extraction and solvent-free oxidation of extracted lipids from poultry industry waste/by-product.

CO2 storage and CaCO3 production using seawater and an alkali industrial by-product

Indirect carbonation is one of the typical carbon capture, utilization, and storage technologies. It is well known, however, that the technology is very difficult to achieve economic feasibility because expensive chemical solvents used account for most of the cost. To overcome this limitation, we performed an experimental study to secure the economic feasibility of the technology by replacing such chemical solvents with nearly costless seawater. For the study, we used cement kiln dust (CKD), which is an alkali industrial by-product, together with seawater. In this paper, we attained CO2 storage and CaCO3 yield despite the use of seawater, which is comparable in both quantitative and qualitative respects to the existing studies using chemical reagents. The CO2 storage and CaCO3 yield were 185 kg-CO2/ton-CKD and 419 kg-CaCO3/ton-CKD, respectively. With the addition of Mg into the seawater, moreover, the amounts could significantly increase to reach 271 kg-CO2/ton-CKD and 615 kg-CaCO3/ton-CKD, respectively. Despite using CKD and seawater containing many impurities, the purity of CaCO3 produced was as high as 99.4%. It was also found that Mg is one component, which can elute Ca from CKD, dissolved in seawater. The solid to liquid ratio was the most influential factor for the Ca elution efficiency, while the CO2 flow rate and NaOH dosage had significant effects on the carbonation efficiency.

Numerical Simulation of Crystalline Silicon Heterojunction Solar Cells with Different p-Type a-SiOx Window Layer

In this study, p-type amorphous silicon oxide (a-SiOx) films are deposited using a radio-frequency inductively-coupled plasma chemical vapor deposition system. Effects of the CO2 gas flow rate on film properties and crystalline silicon heterojunction (HJ) solar cell performance are investigated. The experimental results show that the band gap of the a-SiOx film can reach 2.1 eV at CO2 flow rate of 10 standard cubic centimeters per minute (sccm), but the conductivity of the film deteriorates. In the device simulation, the transparent conducting oxide and contact resistance are not taken into account. The electrodes are assumed to be perfectly conductive and transparent. The simulation result shows that there is a tradeoff between the increase in the band gap and the reduction in conductivity at increasing CO2 flow rate, and the balance occurs at the flow rate of six sccm, corresponding to a band gap of 1.95 eV, an oxygen content of 34%, and a conductivity of 3.3 S/cm. The best simulated conversion efficiency is 25.58%, with an open-circuit voltage of 741 mV, a short-circuit current density of 42.3 mA/cm2, and a fill factor of 0.816%.

The Role of Emotional Contagion in the Distress Exhibited by Grouped Mice Exposed to CO₂.

The 2013 AVMA Guidelines for the Euthanasia of Animals recommends a chamber volume displacement rate of 10% to 30% per minute (v/min) when euthanizing small laboratory rodents with CO₂. Group euthanasia of mice is a common practice, and grouping strangers is often avoided to minimize distress; however, emotional contagion, which occurs between familiar animals but not strangers, has not been studied in the context of group CO₂ euthanasia. This study examined cagemate- and stranger-grouped mice exposed to 10%, 30%, or 50% v/min CO₂ to determine whether emotional contagion plays a role in this context and whether that role is influenced by CO₂ flow rate. Videos of adult male C57BL/6J mice exposed to different CO₂ flow rates were scored for durations of dyspnea, ataxia, and consciousness as well as the numbers of face pawing and jump behaviors. Blood was collected at time of unconsciousness and assayed for ACTH. Cagemates experienced significantly longer durations of conscious dyspnea and ataxia with 10% v/min CO₂ compared with 30% and 50% v/min. Similarly, strangers experienced significantly longer duration of conscious dyspnea with 10% v/min CO₂ compared with 30% and 50% v/min and significantly longer duration of ataxia with 10% compared with 50% v/min. Cagemates showed significantly more jumps with 10% v/min CO₂ compared with 30% and 50% v/min, whereas jumping was unaffected by CO₂ flow rate in strangers. We conclude that more potential for distress exists when cagemate and stranger mice are exposed to a 10% v/min CO₂ flow rate and that emotional contagion may contribute to distress in cagemates at this flow rate. Therefore, we propose that 30% v/min CO₂ should be used for euthanasia of mice, and that 50% v/min should also be considered humane.

Corrosion behavior of N80 steel in CO2-saturated formation water

Purpose This paper aims to explore the influence of CO2 partial pressure, flow rate and water cut on N80 steel corrosion behaviors in the displacement process of oil in glutenite reservoir by CO2 injection. Design/methodology/approach A self-made 3 L high-temperature and high-pressure autoclave was used to conduct corrosion simulation experiments of N80 steel in different CO2 partial pressures, flow rates and water cut (the independently developed oil and water mixing approach can ensure the uniform mixing of oil and water in experiments). Techniques like weight loss and surface analysis were used to analyze the corrosion behaviors of N80 steel under different conditions. Findings Results showed that the average corrosion rate of N80 steel accelerated at varying degrees with the increase of CO2 partial pressure, flow rate and water cut. Excluding that the samples showed uniform corrosion under the two conditions of 0.5MPa CO2 partial pressure and static corrosion, they displayed mesa attack corrosion under other conditions. Besides, with the increase of CO2 partial pressure, the pH value of solution dropped and the matrix corrosion speed rose, hence leading to the increased Fe2+ and CO32− concentration. Meanwhile, a lowered pH value improved the FeCO3 critical supersaturation, thereby leading to an increased nucleation rate/growth rate and ultimately causing the decrease of the dimension of FeCO3 crystallites formed on the surface of the samples. Originality/value The results can be helpful in targeted anti-corrosion measures for CO2/oil/water corrosive environment.

Сверхкритическая СО2 экстракция глицирризиновой кислоты из лакричного корня: оптимизация условий экстракции, используя RSM (response surface metodology)

Extraction of HA from licorice roots was carried out by SC-CO2 with ethanol, as a solvent. Experiments and modeling were denoted by RSM. Licorice root extract was analyzed by chromatography and AAS. The RSM design was used to optimize the variables of the CCE and the GC output. The maximum yield of HA is observed under conditions of 10 MPa, 90.8 and 48.2 °C, 92 minutes and a flow of 1.70 and 1.50 ml/min of CO2 using RSM, respectively. According to RSM, R2 and the modified R2 model are 96.1% and 93.2%, respectively. The accuracy of the GC output model is confirmed by triplet experiments, giving an average extraction yield of 52.2±1.2%, respectively, for RSM. The difference of this study from the data known in the literature lies in the design of experiments on modeling and optimization of the extraction yield. An innovation is the optimization of process parameters via RSM, where the maximum yield is achieved by optimizing the extraction conditions. Estimated optimal yield under specific conditions is confirmed by triple experiments (CHIP) in this study. Notation: P (MPa) – extraction pressure, φ (ml/мин) – CO2 flow rate, R (%) – yield, t (мин) – extraction duration, E (oС) – extraction temperature. RSM is a polynomial model of the 2nd order, to explain the variation in the rate of extraction of GC depending on the variables. The linear terms of temperature, pressure and dynamic time, the quadratic terms of dynamic time and pressure with P ≤ 0.001 are highly reliable. The linear term of the CO2 stream, the quadratic term of temperature, and the terms of interaction t – p and r – the dynamic time with 0.001 < p < 0.01 are significant, while variables with p > 0.01 are insignificant. By applying multiple regression analysis to experimental data, one can obtain second-order polynomial equations.

Selective Extraction of ω-3 Fatty Acids from Nannochloropsis sp. Using Supercritical CO2 Extraction.

In this article, microalgae Nannochloropsis sp. was used for fatty acid (FA) extraction, using a supercritical fluid-carbon dioxide (SF-CO2) extraction method. This study investigated the influence of different pre-treatment conditions by varying the grinding speed (200–600 rpm), pre-treatment time (2.5–10 min), and mixing ratio of diatomaceous earth (DE) and Nannochloropsis sp. biomass (0.5–2.0 DE/biomass) on FAs extraction. In addition, the effect of different operating conditions, such as pressure (100–550 bar), temperature (50–75 °C), and CO2 flow rate (7.24 and 14.48 g/min) on eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) recovery, was analyzed. Experimental data evidenced that, keeping constant the extraction conditions, the pre-treatment step enhanced the FAs extraction yield up to 3.4 fold, thereby the maximum extracted amount of FAs (61.19 mg/g) was attained with the pre-treatment with a ratio of DE/biomass of 1 at 600 rpm for 5 min. Moreover, by increasing both SF-CO2 pressure and temperature, the selectivity towards EPA was enhanced, while intermediate pressure and lower pressure promoted DHA recovery. The highest amount of extracted EPA, i.e., 5.69 mg/g, corresponding to 15.59%, was obtained at 75 °C and 550 bar with a CO2 flow rate of 14.48 g/min, while the maximum amount of extracted DHA, i.e., ~0.12 mg/g, equal to 79.63%, was registered at 50 °C and 400 bar with a CO2 flow rate of 14.48 g/min. Moreover, the increased CO2 flow rate from 7.24 to 14.48 g/min enhanced both EPA and DHA recovery.