Low-quality Oil Research Articles

From Low-Quality Olive Oils to Valuable Bioactive Compounds: Obtaining Oleacein and Oleocanthal from Olive Oils Intended for Refining.

The aim of this work was to recover phenolic compounds such as oleacein and oleocanthal from low commercial value olive oils destined for refining [lampante olive oil (LOO)]. For this, the ability of three extraction systems of phenols from oils was evaluated. A new quick and simple extraction method (NM) for obtaining phenols was developed, consisting of the acidified mixture MeOH/H2O (50:50) (v/v) 0.1% formic acid, and it was compared to a conventional method (CM) widely used for the analytical determination of phenolic compounds in olive oil using MeOH: H2O (80:20) (v/v). NM showed a higher yield for the extraction of oleacein with an increase of 14% compared to CM; no significant differences were observed in the extraction of oleocanthal between the two methods. The third method, using two formulations of deep eutectic solvents (DESs) based on ChCl, showed higher extractive efficiency for the two secoiridoids than CM and NM when DES consisted of ChCl and xylitol. On the other hand, the concentrations of oleacein and oleocanthal were determined in 14 samples of blended oils that were previously classified as extra virgin olive oil and LOO according to EU regulation. LOO contained amounts up to 109.89 and 140.16 mg/kg of oleacein and oleocanthal, respectively. Oleacein (>98%) and oleocanthal (>95%) were successfully recovered from phenolic extracts obtained from LOO oils through chromatographic separation and purification by semipreparative high-performance liquid chromatography. Therefore, these low-quality oils are an inexpensive source of bioactive substances.

A novel bioprocess engineering approach to recycle hydrophilic and hydrophobic waste under high salinity conditions for the production of nutraceutical compounds

The recovery of hydrophobic substrates generated by industrial oily effluents and oil spills represents a growing issue. Here, we describe a low-cost, bio-based, and environmentally friendly method for the mitigation of oil-induced water pollution.We demonstrate that a marine thraustochytrid strain could survive and utilise a record 120 g/L waste cooking oil (WCO) under highly saline conditions. Moreover, the thraustochytrid strain could convert this low-quality oil into high-quality microbial lipids rich in docosahexaenoic acid (DHA) and squalene. DHA and squalene levels were further improved via the co-utilisation of hydrophilic and hydrophobic substrates via de novo and ex novo fermentation. Hydrophobic substrate such as WCO, and volatile fatty acids (VFAs) as hydrophilic substrates generated via acidogenic fermentation increased the DHA content to 40% of total lipids and squalene to 40.47 mg/L. These values are much higher than the 23.96% and 30.21 mg/L obtained with simultaneous de novo and ex novo fermentation using glucose and WCO. The presently described method for producing nutraceutical compounds has two important benefits: (i) it enables the bioremediation of hydrophobic waste from marine environments, and (ii) it offers a sustainable and economical alternative to the use of fish oils and liver from deep-sea sharks as sources of DHA and squalene.

Catalytic vacuum residue upgrading under methane: Evaluation of process feasibility, stability and versatility

The better utilization of low-quality oil resources is becoming more and more crucial for sustainable development due to the depletion of conventional petroleum resources and continuously increasing energy demand. Vacuum residue (VR) is the heaviest part of crude oil accounting for a large proportion in modern refineries, while its utilization routes are generally of low efficiency and high energy intensity, and thus economically and environmentally unfavorable. Methane, as a main component of natural gas, is naturally available with abundant reserve, and the direct use of methane demonstrates unique advantages over hydrogen for the upgrading of a wide spectrum of oils due to the avoidance of natural gas steam reforming step, leading to significantly reduced operational cost and CO2 emission. In this work, a 60-day continuous VR upgrading process under a methane environment was evaluated in a fixed bed reactor with the processing capacity of 20 L/day to validate the feasibility of treating the challenging feedstock and the stability for long-term operation. The feedstock and products collected on day 7, 30 and 60 were selected for comprehensive analysis. The quality indexes of these oil samples were compared in terms of the basic properties including density, viscosity, freezing point, pour point and flash point, the compositional information including characterization K factor, water content, salt content, organochlorine content, ash content, water and sediment volume fraction, total acid number, carbon residue, and asphaltene content, the elemental contents of sulfur, nitrogen and metal impurities, as well as a simulated distillation analysis. All results indicated significantly improved oil qualities and stable operation were maintained for 60 days. Moreover, a Merey heavy crude oil was also upgraded by the same process and favorable product qualities were also observed after a 30-day run, indicating the process was also capable of dealing with other heavy feedstocks. This novel technology with high feasibility, stability and applicability is anticipated to exhibit huge commercial potential for heavy oil valorization in the oil & gas industries.

Design and development of a manually operated oil palm crusher

Palm growers in Bangladesh are currently facing problems to extract crude palm oil from FFB. The traditional method of palm oil processing is time-consuming, laborious, hazardous, and inefficient resulting in the production of low-quality oil. Though mechanical processing is costly but produces good quality Crude Palm Oil (CPO) and the oil recovery rate is high. A low-cost mechanical (manually operated) oil palm crusher was designed and febricated in the workshop of the Department of Farm Power and Machinery, Bangladesh Agricultural University, Mymensingh. The crusher was designed by using Auto-Cad software. It was fabricated according to design parameters. It is fabricated by stainless steel (SS) shaft, stainless steel cylinder, mild steel (MS) hopper, (MS) hollow bars, MS pressure case cap & Bearing. It requires a very small rotating force. The cost of the crusher is only BDT 12000, which is within the buying capacity of the farmers of Bangladesh. Crusher was mounted on the table or bench. At first 500 gm fresh palm fruits were taken for experimentation. About 300 gm mesocarp and 200 gm oil palm kernel (nuts) were found from 500 gm oil palm fruits. Heating 300 gm mesocarp about 15 minutes and was weighted 280 gm mesocarp due to moisture loss. About 62 gm crude palm oil, 124 gm oil cake, 88 gm skum were collected from 280 gm mesocarp. The average m.c (wb) of fresh palm fruit was found 20.73%. The crushing capacity of the mesocarp of the crusher was o.84 kg/hr. The rotating speed of the screw was 26 rpm. Crude oil percentage was found 22.14%. The total time to extract 62 gm crude palm oil from 500 gm of fresh fruit was 1hr and 15 minutes. The weight of the crusher is 11 kg which is easy to operate by one man. The overall performance of the crusher was found quite satisfactory and could be useful for smallholder palm growers in Bangladesh.
 Progressive Agriculture 32 (1): 60-70, 2021

The development of new homogenous and heterogeneous catalytic processes for the treatment of low grade palm oil

Low grade crude palm oil (LGCPO) presents as an attractive option as feedstock for biodiesel production due to its low cost and non-competition with food resources. Typically, LGCPO contains high contents of free fatty acids (FFA), rendering it impossible in direct trans-esterification processes due to the saponification reaction. Esterification is the typical pre-treatment process to reduce the FFA content and to produce fatty acid methyl ester (FAME). The pre-treatment of LGCPO using two different acid catalysts, such as titanium oxysulphate sulphuric acid complex hydrate (TiOSH) and 5-sulfosalicylic acid dihydrate (5-SOCAH) was investigated for the first time in this study. The optimum conditions for the homogenous catalyst (5-SOCAH) were determined as: 1.5 wt% of acid catalyst dosage, 60 °C reaction temperature, 8:1 methanol molar ratio at 60 min. For the heterogeneous TiOSH, higher catalyst dosages such as 7 wt% is required with a methanol loading of 10:1 (molar ratio) at 120 min to reduce the initial FFA to less than 3%. Under these optimum conditions for both types of catalysts; the FFA levels were reduced from 11.3 % to less than 3 %, individually. This study introduces for the first time two types of acidic catalysts with high catalytic activity for the esterification of FFA content in low grade oils for biodiesel production which could be used for the treatment of wide range of low quality oils.

Composition Profiling and Authenticity Assessment of Camellia Oil Using High Field and Low Field 1H NMR.

Camellia oil (CA), mainly produced in southern China, has always been called Oriental olive oil (OL) due to its similar physicochemical properties to OL. The high nutritional value and high selling price of CA make mixing it with other low-quality oils prevalent, in order to make huge profits. In this paper, the transverse relaxation time (T2) distribution of different brands of CA and OL, and the variation in transverse relaxation parameters when adulterated with corn oil (CO), were assessed via low field nuclear magnetic resonance (LF-NMR) imagery. The nutritional compositions of CA and OL and their quality indices were obtained via high field NMR (HF-NMR) spectroscopy. The results show that the fatty acid evaluation indices values, including for squalene, oleic acid, linolenic acid and iodine, were higher in CA than in OL, indicating the nutritional value of CA. The adulterated CA with a content of CO more than 20% can be correctly identified by principal component analysis or partial least squares discriminant analysis, and the blended oils could be successfully classified by orthogonal partial least squares discriminant analysis, with an accuracy of 100% when the adulteration ratio was above 30%. These results indicate the practicability of LF-NMR in the rapid screening of food authenticity.

Identification of Tyrosyl Oleate as a Novel Olive Oil Lipophenol with Proliferative and Antioxidant Properties in Human Keratinocytes.

Lipophenols are an emerging subclass of phenolic compounds characterized by the presence of a lipid moiety. Recently, hydroxytyrosyl oleate (HtyOle), a derivative of hydroxytyrosol, has been identified in olive oil and by-products. Furthermore, HtyOle possesses anti-inflammatory, antioxidant, and tissue regenerating properties. In this work, the potential occurrence of tyrosyl oleate (TyOle) in olive oil was investigated based on the hypothesis that its precursors tyrosol and oleic acid, both present in relatively high amount can be coupled together. Moreover, TyOle effects have been investigated in human keratinocytes to verify its proliferative and antioxidant properties. The quantitative determination of TyOle was carried out by the external standard method in liquid chromatography coupled with mass spectrometry (LC/MS), in negative mode using multiple reaction monitoring (MRM). The proliferative properties of TyOle on immortalized human keratinocytes (HaCat) were evaluated by 3-(4,5-dimethylthiasol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Morphological changes were observed by fluorescent staining with phalloidin (for F-actin) or 4,6-diamidino-2-phenylindole (DAPI, for chromatin) dye. The antioxidant activity was assessed at the level of production of mitochondrial reactive oxygen species (ROS) induced with UV exposure. TyOle was identified in all the oil samples investigated. Interestingly, TyOle concentration was higher in defective or low-quality oils than in extra virgin oils. The formation of TyOle likely occurs during the crushing and kneading processes and its concentration is related to the increase of rancidity and of the concentration of free precursors. Herein we show that TyOle induced an increase in the viability of HaCat cells and cytoskeletal remodeling.

Iron (II) impregnated double-shelled hollow mesoporous silica as acid-base bifunctional catalyst for the conversion of low-quality oil to methyl esters

To promote the use of low-quality oils in producing biodiesel, a bifunctional acid-base catalyst Fe/DS-HMS-NH2 is fabricated using the two-step condensation technique. The obtained Fe/DS-HMS-NH2 is of a doubled shell structure in spherical shape with a uniform size of 156 nm. Its hollow core (with a diameter of 86 nm) and two spatial shells with different active sites enables the esterification and transesterification reactions to be accomplished in a one-pot synthesis. The influences of four independent reaction variables on the yield of fatty acid methyl esters YF was studied, including catalyst loading mc, reaction time t, reaction temperature T, and the methanol to degummed palm oil mass ratio rm/o. The highest yield was obtained at 85.36% (w/w) when mc = 6% (w/w), t = 4.5 h, T = 60 °C, and rm/o = 6:1. The Fe/DS-HMS-NH2 shows a good recyclability with YF > 80% (w/w) up to three reaction cycles.

Enhancement of Biodiesel Production from High-Acid-Value Waste Cooking Oil via a Microwave Reactor Using a Homogeneous Alkaline Catalyst

In this study, low quality oils (waste cooking oils) with high acid value (4.81 mg KOH/g) were utilized as the feedstocks for a transesterification reaction enhanced by additional microwave power and the use of an NaOH catalyst. The kinetics of the transesterification reaction under different reaction times and temperatures was studied. It was found that in the microwave-assisted transesterification reaction, the optimum conditions under a microwave power of 600 W were as follows: an NaOH catalyst of 0.8 wt %, a 12:1 molar ratio of methanol to oil, a reaction time of 2 min, and a reaction temperature of 65 °C. The conversion of waste cooking oil into biodiesel reached 98.2% after this short reaction time. This result conformed to 96.5% of the standard value of Taiwan CNS 15072. In addition, with increases in the reaction temperature from 55 to 65 °C, the reaction rate constant increased from 0.635 to 2.396 min−1, and the activation energy required for the transesterification reaction was 123.14 kJ/mole.

Fabrication of Heterogeneous H6PV3MoW8O40/AC-Ag Catalyst for Biodiesel Production from Low-Quality Oils

Herein, we first modified commercial activated carbon (AC) with different metal ions (Cs+, K+ and Ag+), and then H6PV3MoW8O40 acids were incorporated into as-modified supports。The 35%H6PV3MoW8O40/AC-Ag hybrid catalyst showed highly catalytic performance for transesterification of soybean oil. The best oil conversion of 91.3% was achieved under optimized conditions: methanol/oil ratio of 30:1, reaction time of 10 h, reaction temperature of 140 °C and catalyst dosage of 8 wt.%. Characterization results of XRD, IR, ICP and TG indicated that H6PV3MoW8O40 was highly dispersed on the AC-Ag support as the loading was less than 35%. Proton exchange with Ag may contribute to the highly dispersion of H6PV3MoW8O40 on the support, thereof leading to the increased stability. The as-prepared 35%H6PV3MoW8O40/AC-Ag catalyst was recycled and had good resistance to free fatty acid (FFA) and water, which were included in low-quality oils. Moreover, the solid acid catalyst could simultaneously catalyze the transesterification of soybean oil and esterification of FFA, and a probable mechanism of the catalytic process was also proposed. All the features of this novel solid catalyst are more advantageous than homogenous H6PV3MoW8O40 catalyst, successfully creating an efficient and sustainable approach of biodiesel production especially from low-quality oils.

Pyrolysis-Gas Chromatography/Mass Spectrometry Analysis of Oils from Different Sources

Regenerated gutter oil (i.e., waste oil) accounts for 10% of the edible oil market, which has caused serious food safety issues. Currently, there is no standard protocol for the identification of the gutter oil. In this study, the pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) method was employed to analyze eleven oil samples including edible vegetable oils (tea oil, corn oil, olive oil, sunflower oil, peanut oil and blend vegetable oil) and waste oils (used frying oil, lard, chicken fat, inferior oil and kitchen waste grease). Three factors of pyrolysis temperature, reaction time and sample volume were investigated to optimize the analytical parameters. The optimal pyrolysis conditions were determined to be 600°C, 1 min and an injection volume of 0.3 μL. Five characteristic components (tetradecane, z,z-9,12-octadecadienoic acid, decanoic acid-2-propenyl ester, 17-octadecenoic acid, and z-9-octadecenoic acid) were found in all oil samples. The existence of C11-C16 olefins in the pyrolytic products of the animal fats and the other low-quality oils could be utilized to distinguish vegetable oils from gutter oils.

Biodiesel Production from Low-Quality Oils Using Heterogeneous Cesium Salts of Vanadium-Substituted Polyoxometalate Acid Catalyst

This research aims at developing an efficient and reusable catalyst to improve biodiesel production processes. To achieve this, a vanadium-substituted polyoxometalate (POM) acid, namely H6PV3MoW8O40, was firstly prepared, and then the heterogenzation of the homogeneous Keggin-type heteropoly acids was performed by the partial proton substitution by monovalent large cesium cations with the formation of solid Cs2H4PV3MoW8O40 catalysts. Several techniques, such as X-ray diffractometer, Fourier transform infrared, coupled plasma–atomic emission spectrometry, Diffuse reflectance ultraviolet–visible spectrum, thermal gravimetric analysis and N2 adsorption–desorption techniques, were employed to characterize the as-prepared solid catalyst. The solid acid catalyst had the capacity to catalyze both the transesterification of soybean oil and esterification of free fatty acids (FFAs) simultaneously, providing an efficient production process for the production of biodiesel from low-quality oils. Under the operational conditions of a methanol/oil molar ratio of 30:1, a catalyst dosage of 5 wt.%, a reaction temperature of 140 °C, and a reaction duration of 8 h, an oil conversion of 92.2% was attained with the total FFA transformation to biodiesel. Furthermore, the catalyst could be reutilized for several cycles with no significant drop in its activity, thus having great potential for application with a bright perspective in the production of biodiesel, especially from low-quality oil feedstocks.

Grafting copolymerization of dual acidic ionic liquid on core-shell structured magnetic silica: A magnetically recyclable Brönsted acid catalyst for biodiesel production by one-pot transformation of low-quality oils

The objective of the current research is to prepare an efficient and magnetically separable Brönsted acid catalyst for one-pot transformation of low-quality oils to biodiesel. In this premise, the core–shell structured magnetic composites were firstly prepared by coating of silica shells on magnetic Fe3O4 nanoparticles. Thereafter, the grafting copolymerization of dual acidic ionic liquids (ILs, 1-vinyl-3-(3-sulfopropyl)imidazolium hydrogen sulfate as an monomer and 1.4-butanediyl-3,3′-bis-1-vinylimidazoliu hydrogen sulfate as a cross-linker agent) on the magnetic silica composite was conducted to impart the richer Brönsted acidic functionality on the support. The detailed catalyst characterization results showed that the magnetic silica support was really formed, and moreover the polymeric acidic ILs were successfully grafted on the magnetic support. The so-prepared solid catalyst had a large surface acidity (3.93 meq H+/g) and strong magnetism (27.5 emu/g). Benefiting from the synergism between the polymeric ILs and magnetic porous support, this developed catalyst displayed good catalytic activities toward both the transesterification of soybean oil and esterification of free fatty acids (FFAs), which endowed it to be a robust solid acid catalyst for one-pot biodiesel production from low-quality acidic oils. The solid catalyst could be simply recovered by an external magnet with minor loss of catalytic activity within five cycles, and further showed insensitivities to moisture and FFAs present in the feedstocks, possessing both economic and environmental advantages for the application in biodiesel production especially from the low-quality oils.

Synthesis of heterogenized polyoxometalate-based ionic liquids with Brönsted-Lewis acid sites: A magnetically recyclable catalyst for biodiesel production from low-quality oils

The aim of this study is to develop a magnetically recyclable acid catalyst for biodiesel production from low-quality acidic oils. To achieve this, polyoxometalate (POM)-based sulfonated ionic liquids (ILs) bearing Brönsted-Lewis acid sites, namely (Py-Ps)PMo, were firstly prepared by reaction of pyridine with 1,3-propanesultone, followed by anion exchange with phosphomolybdic acid (HPMo). Thereafter, the so-prepared ILs were loaded on the amino-functionalized metal–organic framework (CoFe2O4/MIL-88B(Fe)-NH2) to synthesize the recoverable solid catalyst. The obtained CoFe2O4/MIL-88B(Fe)-NH2/(Py-Ps)PMo catalyst was characterized by several techniques, which provided an evidence that the acidic ILs were loaded on the magnetic support by strong charge interaction effect. This catalyst showed highly catalytic activities toward the transesterification of soybean oil and esterification of free fatty acids (FFAs), making it to be applicable for one-pot production of biodiesel from low-quality acidic oils. The catalytic performance was originated from the combination of the characteristics of Brönsted-Lewis acid sites and porous structure of the support. Moreover, the catalyst could be simply recovered by a permanent magnet and reutilized for several times with no remarkable attenuation of catalytic activity. Thus, the IL based solid catalyst possessed the potential of efficient and environmentally benign production of biodiesel practically from the low-quality oils.

Chemical Fingerprinting of Olive Oils by Electrospray Ionization-Differential Mobility Analysis-Mass Spectrometry: A New Alternative to Food Authenticity Testing.

Recently, the olive oil industry has been the subject of harsh criticism for false labeling and even adulterating olive oils. This situation in which both the industry and the population are affected leads to an urgent need to increase controls to avoid fraudulent activities around this precious product. The aim of this work is to propose a new analytical platform by coupling electrospray ionization (ESI), differential mobility analysis (DMA), and mass spectrometry (MS) for the analysis of olive oils based on the information obtained from the chemical fingerprint (nontargeted analyses). Regarding the sample preparation, two approaches were proposed: (i) sample dilution and (ii) liquid-liquid extraction (LLE). To demonstrate the feasibility of the method, 30 olive oil samples in 3 different categories were analyzed, using 21 of them to elaborate the classification model and the remaining 9 to test it (blind samples). To develop the prediction model, principal component analysis (PCA) and orthogonal partial least-squares discriminant analysis (OPLS-DA) were used. The overall success rate of the classification to differentiate among extra virgin olive oil (EVOO), virgin olive oil (VOO), and lampante olive oil (LOO) was 89% for the LLE samples and 67% for the diluted samples. However, combining both methods, the ability to differentiate EVOO from lower-quality oils (VOO and LOO) and the edible oils (EVOO and VOO) from nonedible oil (LOO) was 100%. The results show that ESI-DMA-MS can become an effective tool for the olive oil sector.

Classification Approach to Assay of Crude Oils with Different Physicochemical Properties and Quality Parameters

An approach to crude oil assay based on the consistent application of two heterogeneous classifications of oils is proposed: according to the quality index and physicochemical parameters. The methodological issues of the classification approach to oil analysis, implemented in the form of a two-stage procedure, are described. The approach is illustrated by an example of analysis of the characteristics features of different types of tight oils in Russia. The analysis used data from 25.190 oil samples with abnormal properties and 10 500 oil samples with complex modes of occurrence. At the first stage, the analysis has been carried out using the classification of tight oils according to the quality index; as a result, the oils were divided into three homogeneous classes: low, medium, and high quality oils. At the second stage of the analysis, the classification of oils by physicochemical characteristics has been used, taking into account the density; viscosity; sulfur, resin, asphaltene, wax, vanadium, nickel, and light end contents; gas saturation of oil; etc. The analysis made it possible to establish the characteristic features of the physicochemical properties of tight oils belonging to different quality classes.

Presence of palm oil in foodstuffs: consumers’ perception

PurposeThe purpose of this paper is to determine the presence of palm oil in food products on sale, and to study and compare consumers’ opinions about this oil type in Spain (importing country) and Peru (producing country).Design/methodology/approachRecent news published in both countries, which could influence consumer perceptions, were analysed. A study on the labelling of foodstuffs in Spain was carried out, as was a survey with Spanish and Peruvian consumers.FindingsPalm oil was found in a large number of products and in a wide range of foods, especially those from the bakery sector. The percentages of saturated fats varied substantially within the same product type. Spanish consumers showed much more interest in the labelling and information on nutritional properties, especially energy values, saturated fats and sugars, while Peruvians focused more on energy values, and protein, vitamin and mineral contents. In Spain, palm oil was considered the worst quality fat/oil and had a clearly negative effect on both health and the environment. In Peru, palm oil was neither perceived by the majority of respondents as low quality oil nor associated with negative health effects. However, they were aware of the environmental problems that could result from its production.Originality/valueThese results confirm that the food industry should make efforts to reduce or replace palm oil in foods, mainly in Spain, as most consumers believe that palm oil negatively affects their health and the environment.

Research of exhaust emissions by chainsaws with the use of a portable emission measurement system

ABSTRACTAnthropogenic activities in the environment have an impact on climate change. Among these activities is the use of the chainsaw which plays an important role by releasing greenhouse gas emissions in the atmosphere. Hence, the need for research on improved logging operations is of importance. The present study compares carbon monoxide (CΟ) and nitrogen dioxide (NO2) emissions generated by the engines of one catalytic chainsaw and two conventional chainsaws, of which one is professional and the other amateur. Measurements were carried out under three functional modes (infrequent accelerator use, use of quality oils, use of clean filters). Measurements that were conducted under normal conditions were named “witness measurements” and were used for future comparisons. Additionally, a set of measurements for CΟ and ΝΟ2 emissions was collected under different operation modes for all three types of saws (frequent accelerator use, use of low-quality oils, use of impure filters). Data collection was carried out in real conditions using a portable gas detector. Average concentration values of CΟ and ΝΟ2 under normal conditions for all three types of chainsaws found in the air of the operator’s breathing zone were 88.32 ppm and 0.07 ppm, respectively. Results show that CO concentrations exceed the permissible exposure limit (50 ppm), whereas CO concentrations in excess of the short-term exposure limit (300 ppm) were only found in the case of the amateur chainsaw operated with low-quality oils. These results are of use towards efforts to reduce the CO and NO2 to the atmosphere.

The effect of polyphenols and vitamin E on the antioxidant status and meat quality of broiler chickens fed low-quality oil.

The aim of this study was to determine the effect of vitamin E and polyphenols on the antioxidant potential and meat quality of broiler chickens fed diets supplemented with low-quality oil. The experimental materials comprised 120 male Ross 308 broilers (six treatments, 10 replications, two birds per replication). Dietary supplementation with vitamin E and/or polyphenols was applied in the following experimental design: group I (negative control) – without supplementation without low-quality oil; group II (positive control) – without supplementation low-quality oil; group III – supplementation with 100 mg kg of vitamin E low-quality oil; group IV – 200 mg kg of vitamin E low-quality oil; group V – 100 mg kg of vitamin E and 100 mg kg of polyphenols low-quality oil; group VI – 200 mg kg of polyphenols low-quality oil. Rapeseed oil oxidised under laboratory conditions was added to the diets of broiler chickens from groups II to VI. The applied antioxidants had no effect on the growth performance of chickens fed oxidised oil. Increased dietary inclusion levels of vitamin E and/or polyphenols improved the antioxidant status in the blood and increased the content of non-enzymatic antioxidants in the liver and breast muscles of broilers fed low-quality oil. The tested antioxidants had no influence on carcass quality parameters in chickens fed oxidised oil. However, birds fed diets with the addition of vitamin E were characterised by a higher gizzard weight and higher pH of gizzard digesta. Dietary supplementation with vitamin E and polyphenols or polyphenols alone contributed to a lighter colour and lower pH of breast muscles and an increase in the content of fat and ash in the breast muscles of broilers fed oxidised oil. The breast muscles of birds given 100 or 200 mg kg of supplemental vitamin E were characterised by higher concentrations of n-6 polyunsaturated fatty acids (PUFAs) and hypocholesterolemic fatty acids (DFAs), a more desirable ratio, and a lower atherogenicity index (AI). Polyphenols combined with vitamin E can be a valuable component of diets for broiler chickens when the problem of low-quality oil occurs.

Upgrading low-quality oil shale using high-density gas-solid fluidized bed

Oil shale is a high-value fuel resource and its global output is gradually increasing with time. Based on the analysis of physical properties of oil shale, a sorting process for high-density dense-phase gas-solid separation using fluidized bed is proposed. During the separation process in a gas-solid separation fluidized bed, a binary mixture of oil shale’s mineral powder and ferrosilicon powder is formed. This paper systematically analyzes the separation characteristics of ferrosilicon powder. Furthermore, the influence of different factors (fluidization number N, and oil shale’s powder grade) on the degree of mixing of particles in the binary mixture and the influence of binary heavy medium ratio on the stability of bed are also studied. The results show that the weight of ferrosilicon is prone to stratification and grading in the fluidized bed due to its own particle size composition. The mixing process of oil shale mineral powder and ferrosilicon powder plays a crucial role in the adjustment of bed density. The density gradually narrows with the increase in the value of fluidization number. For the same fluidization number, the bed density decreases with the increase in the mass fraction of oil shale's mineral powder. The oil shale is separated under optimized operating conditions (particle size of 0.5–0.9 mm, mixing ratio of 10%, and fluidization number of 1.4). The yield of concentrate is 27.18%, while the oil content is 10.76%. Furthermore, the yield of tailings is 77.61%, whereas the oil content is 1.46%. Additionally, the separation precision (possible error) E has the value of 0.113.