Experimental study on essential anise star oil purification in vacuum batch distillation

Vietnam is one of the world’s largest annual anise harvest countries. However, products from anise are mainly in the form of dried anise fruit and crude star anise essential oil with low economic value. The main component of the star anise essential oil is trans-anethole which needs to be purified to produce higher-value products. This study focused on building an experimental system for purifying star anise essential oil by a batch distillation column working at vacuum pressure. The products obtained during the purification process were analysed by gas chromatography-mass spectrometry (GC-MS). Analytical results were used to evaluate the ability to separate volatile impurities in the crude star anise essential oil. Results showed that the bottom temperature of the tower below 150oC, corresponding to a vacuum pressure of less than 0.1 bar, can reduce the thermal decomposition of essential oils. The volatile components, such as α-pinene, β-phellandrene, limonene, and linalool, were thoroughly separated at the top of the tower. The purified star anise essential oil was from the bottom of the distillation and had the anethole composition of over 88% of mass fraction (wt.%). Anethole recovery efficiency was 98.5 and 88.8% at a pressure of 0.1 and 0.08 bar, respectively. The bottom product can have a higher anethole composition if increasing the column height, the reflux ratio, and decreasing the pressure and the quality of impurities removed at the top is increased.The experimental results are helpful for the calculation, design, manufacture, and operation of an industrial-scale essential oil purification system.

Recyclable Ag/TiO2@PDMS Coated Cotton Fabric with Visible-Light Photocatalytic for Efficient Water Purification

Multifunctional materials for water purification have attracted great attention due to the increased water pollution problems. However, fabricating the low-cost and recyclable separation material is still a challenge. Herein, we developed an Ag/TiO2@PDMS coated cotton fabric with self-clean ability, high flux, superior visible-light photocatalysts ability, and recyclability via the “powder + glue” strategy. The composites exhibit superhydrophobic (water contact angle 157°), and high separation efficiency. The separation efficiency of 20 times of repeated use remains 16322 Lm−2h−1 and the degradation rate of methylene blue (MB) remains almost no change. The high oil purification, catalytic property, excellent stability in harsh condition and recyclability enables the material as a satisfactory candidate for water purification.

Plant for cleaning oils from oxidation products

The study aims to substantiate the parameters and operating mode of the oil purification device from oxidation products to improve the efficiency of the use of lubricants. The methods of mathematical analysis and mathematical statistics, comparative comparison, generalization, and testing methods of agricultural machinery are used in the research process. It is established that engine oils are intensively polluted by oxidation products during processing, thereby accelerating the friction process due to the overload of tractor engines. During the performance of agricultural work in the oil composition, the content of oxidation products in the form of carbon, carbon dioxide, and asphalt products increases by 1.2%. Analytical coupling dependences for the process of cleaning motor oils from oxidizing products are obtained, and the dependence of the cleaning efficiency on the device parameters is established. The developed device consists of a container for collecting oils, a steam generator, a container for a sump mixer, a separate container for pure and sedimentary oils, and a vessel for re-collecting acetone. An installation has been developed to implement the technology of collecting and renewing oils in the conditions of the farm. In this case, the amount of contamination and the composition of oils is determined, and the operating mode of the device is selected for their resumption.

Ultralight, Strong and Renewable Hybrid Carbon Nanotubes Film for Oil-Water Emulsions Separation

A novel ultralight superhydrophobic-superoleophilic hybrid Carbon Nanotubes (CNTs) film with double-layer structures is fabricated by using vacuum filtration method. The CNTs film can separate various surfactant-stabilized water-in-oil emulsions with a separation efficiency higher than 99.3%. Moreover, the hybrid films can be regenerated through a simple and rapid combustion process within 2 s. In addition, the CNTs film still retains good hydrophobic properties under the conditions of physical abrasion, and strong acidic and alkaline solutions, which shows the excellent durability. The hybrid CNTs film is ultralight, stable, and easily stored and reused. The outstanding features of the obtained CNTs films we present here may find many important applications in various fields like oil purification and wastewater treatment.