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Nowadays, intensive agriculture correlated with the impact of climate change has led to nutrient soil depletion and the salinization of agricultural lands, making them unsuitable for conventional agricultural crops, with a direct impact on the food industry. Therefore, it is necessary to find sustainable alternative solutions that satisfy the needs of both consumers and food production. One such solution may be represented by salt-tolerant species that can fulfill food requirements. One of the most promising salt-tolerant plant species that can be used is Salicornia europaea L. The present work was conducted in greenhouse conditions, and the adaptability of the species on different cultivation substrates was investigated by means of monitoring the plant indicators such as cuticle, epidermis, parenchyma, polyphenols content, and minerals. Moreover, the correlation between the polyphenol and mineral contents was highlighted. Therefore, three cultivation substrates with different levels of salinity/electrical conductivity were used. The reference (I) for biochemical indicators was represented by the plant grown in natural salinity conditions in the Southeast region of Romania. The results indicate that Salicornia europaea L. can be grown on different cultivation substrates other than salted soils, the plant showing the capacity to accumulate bioactive compounds similar to natively grown ones.

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The aim of this work is to optimize the supercritical liquefaction process of rapeseeds in order to produce a bio-oil with low viscosity. Reaction parameters, such as reaction temperature, residence time, and solvent to biomass ratio, were studied. Response surface methodology (RSM) based on central composite design (CCD) was used to determine the optimum operating conditions to minimize the bio-oil viscosity. The low bio-oil viscosity of 5.90 mPa.s was obtained at the optimal operating conditions of 280 degrees C, 40 min, and methanol/biomass mass ratio of 5.5/1, at pressure within the batch reactor of 124.59 bars. At these optimal conditions, the bio-oil yield was high and reached around 80wt%, while its heating value was about 38.36MJ/kg. It was proved that the reaction temperature and methanol/biomass ratio were the most influencing parameters on bio-oil viscosity according to the ANOVA results. The predicted values from the RSM model was in good agreement with the experimental results. The GC-MS analysis showed that the bio-oil is mainly composed of methyl esters, which are the main components of biodiesel. This study revealed the complete supercritical transesterification of lipid into alkyl esters resulting in a low amount of triglycerides, monoglycerides, diglycerides, and glycerin, identified by GC-FID. The results will provide useful guidance for predicting other physical properties of bio-oil following a similar methodology to that used in this work. In addition, bio-oil could be used for biodiesel fuel production but after hydrodeoxygenation treatment.

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This paper aimed to investigate the conversion of sunflower seeds to bio-char through hydrothermal liquefaction (HTL) process. The effect of reaction temperature (X-1, 240-320 degrees C), residence time (X-2, 10-60 min) and biomass/solvent ratio (X-3 , 20-80%) was analyzed and optimized using full factorial design of response surface methodology. The developed regression model gave accurate predictions and fitted well with the experimental results with a determination coefficient R-2 of 92.89%. The optimized conditions for bio-char production have been found to be 240 degrees C, 60 min and 20%, temperature, time and biomass to solvent ratio, respectively. These optimum values were validated by experimental runs which produced a bio-char yield of 32.24 wt% with higher heating value of 32.24 MJ/kg and high carbon content of 65.45%. The quadratic model revealed a strong interaction between reaction temperature and residence time, as well as, reaction temperature and biomass/solvent ratio. Based on the thermal decomposition mechanism of bio-char, derivative thermogravimetry revealed two major peaks were observed at 275 and 400 degrees C indicating the improvement in thermal stability of the bio-char after HTL process. In addition, the obtained bio-chars were different in terms of their organic and ash content depending on the HTL operating conditions.

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New global directions align agricultural land resources towards food production; therefore, marginal lands could provide opportunities for second-generation energy crops, assuming that in the difficult conditions of plant development, productivity can be maintained at relatively high levels. Sustainable bioenergy production on marginal lands represents an ambitious objective, offering high-quality biofuels without competing with the agri-food industry, since it allows successful feedstock production to be performed on unmanaged areas. However, marginal land feedstock production generally shows several agronomic, techno-economic, and methodological challenges, leading to decreases in the obtained quantities of biomass and profitability. Sweet Sorghum is a technical plant that has the needed qualities to produce large amounts of biofuels on marginal lands. It is a high biomass-and sugar-yielding crop, characterized by a high photosynthetic efficiency and low fertilizer requirement, is resistant to drought, and adapts well to different climate areas. Marginal lands and contaminated soils provide a favorable development environment for plants such as sweet sorghum; however, in-depth research studies on biomass productivity must be carried out, as well as advanced quality evaluation of the products, in order to develop combined technologies that use resources efficiently. The present study starts with a comparative evaluation of two sweet sorghum crops established on both marginal and regular lands, assessing plant development characteristics and juice production, and an evaluation of bioethanol generation potential. The vegetal wastes resulting from the processing were treated by pyrolysis, with the aim of maximizing the productivity of high-quality liquid biofuels and chemicals. The charcoal obtained in the thermal processes was considered as an amendment of the soil so that marginal land quality could be improved over time. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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The paper presents the biological variation in biochemical compounds of fruits belonging to Ribes nigrum L. species during the maturation process. The fruits from two varieties were collected in the following phenological stages: early first fruits (SIII), advanced first fruit (SIV), harvesting maturity (SV), and consumption maturity (SVI). The extracts were subjected to analysis. Total phenolic content (TPC) expressed as gallic acid equivalent (GAE), total flavonoid content (TFC) expressed as rutin equivalent (RE), and free radical scavenging activity (FRSA) expressed as mg/mL ascorbic acid equivalent (AAE), and gas-chromatographic profile were determined. The phenolic content differed considerably during the maturation process. Thus, the maximum value of TPC was achieved by 'Kzvana' fruits in the SV stage with 7.36 mM GAE/ml extract. The flavonoid content was highlighted in 'Roxia' fruits in the SVI stage with 1.24 mM RE/mL extract. With regard to FRSA, 'Kzvana' fruits have better activity. Also, the aromatic profile was characterized using gas chromatographic analysis.

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Currently, the entire world is facing major challenges related to agricultural practices and heavy metals contaminations of agricultural systems and food production. On the other hand, the structure, texture, and properties of the soil have deteriorated as a result of intensive conventional agriculture based on the addition of different inputs. Along with these, toxic metals affect agricultural soils, crops, food chain, becoming a major threat to living systems. Among these is chromium (Cr), an element naturally occurring in rocky soils and volcanic dust. The increased use of chromium in several multiple activities causes soil and water contamination. Differently from other heavy metals like lead, cadmium, and copper, chromium presents different degrees of toxicity depending on its chemical form. In the present review, we present data regarding chromium abundance in agricultural systems, factors favouring the absorption in the plant and bioaccumulation in different organs and tissues, bioaccumulation and translocation factors, its toxicity in plants, animals, and human through the food chain, and how it can be quantified using different types of analysis.

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Bio-oil production from sunflower seeds, as model components, was carried out in supercritical hydrothermal liquefaction conditions. The effects of operating parameters such as temperature, time, and biomass/solvent mass ratio were investigated. Response surface methodology based on full factorial design was utilized to optimize the operating conditions using Design Expert software. From the analysis of variance, the most influential factor of each experimental design response was identified and a regression model was derived. The results show that the quadratic polynomial model provided accurate predictions for bio-oil yield and its viscosity, with a determination coefficient R-2 of 0.9120 and 0.9351, respectively. The optimum condition was 286.21 degrees C, a reaction time of 12 min, and 20% of biomass/solvent mass ratio. These conditions led to obtain 79.96 wt.% of bio-oil with a viscosity of 18.09 mPa s. The produced bio-oil was subjected to different analyses and characterized by gas chromatography-mass spectrometry. Besides, ether esters were identified as major components. Bio-oil properties were evaluated according to standard norms, and the results suggest the need of further upgrading step to improve its quality.

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The present study is part of a comprehensive study dedicated to the cultivation of halophytes species on salt affected soils, aiming on new value chains development from obtained biomass. The work is conducted on the monitoring the degree of soil purification, the biomass production and seeds yield, and their chemical composition. In this context, the paper contains information related to the oil content of Portulaca saliva sp. seeds, in order to produce 2nd generation biofuels. Extraction of oil from seeds via traditional method (Saxhlet method) and accelerated solvent extraction (ASE) were carried out. ASE method was applied because requires small quantities of solvent, sample and operating time. ASE appear to be the most suitable method and the optimal conditions were: pressure - 10.34 AlPa, temperature - 105 degrees C, residence time - 10 min, solvent - petroleum ether, extraction ratio of 1:40, dynamic extraction time - 30 min. and 0.3 g diatomaceous earth. The highest oil recovery achieved was 33.4%.

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In this moment plastics provide a fundamental contribution in all activity fields: cars, aircraft, electronics, building, domestic daily activities, packing, etc. so the consumption of plastics has increased drastically. The disposal of plastic composite wastes is a serious environmental problem as they are not biodegradable. As a consequence, our work is focused in recycling of carbon fibers and glass fibers from waste composites through pyrolysis and partial oxidation.

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Applied pyrolysis is used in this work as a treatment technique for hydrocarbon fraction recovery of used lubricating oils (ULO) with the aim of its further energetic valorisation. Applied pyrolysis bring also the advantage of a better management of metallic compounds that will be concentrated in the solid residue. In this work, technical parameters have been evaluated to establish their influence on the process evolution with the aim of identifying the adequate parameters for obtaining the maximum liquid fraction. It was found that, for an equilibrated energy balance, the final pyrolysis temperature should not exceed 460 degrees C and the main parameter that affect the pyrolysis oil yield and its physical-chemical properties is the heating rate in the thermal range of decomposition. Activated Zeolites (HZSM-5 type) and Na2CO3 were used as catalysts. The catalysed pyrolysis tests were performed using direct contact between ULO and catalyst, the materials being mixed before processing. Experimental results showed that in non-catalysed pyrolysis an increasing heating rate is slightly reducing the yield of liquid fraction. On the other hand, by using catalysts, the liquid fraction is decreasing. Thus, the highest liquid ratio (81 wt. %) was obtained when the Na2O3 is used and the process is run under a heating rate of 3-5 degrees C/min. But then, the zeolite HZSM-5 is leading to the highest overall conversion, 95 wt. % at 15-17 degrees C/min, and is positively influence the formation of gas fractions.

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This paper presents the elemental content found in two saline soil samples with a certain electrical conductivity and the differences between two variants of extraction. The soil samples collected from a region in South-East of Romania affected by salinization process were investigated using a semi quantitative (SMA) inductively coupled plasma with mass spectrometry analysis (ICP-MS). Thus, the multi-elemental analysis of soil samples was preceded by one-step digestion in a high-pressure microwave system. For matrix destruction two mixtures of reagents were used: A - HNO3, HCl and H2O2 in 3:1:1 (v/v), and B - HNO3, HCl 3:1 (v/v). The electrical conductivity was realized using an adapted method, and the value was up to 10000 dS/m. Following semiquantitative analysis, the results showed that both of extraction methods showed the same elemental composition, the difference being only of the quantity of each element. Regarding the extraction efficiency, mixture A was more suitable for this type of soil.

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In this paper, catalyzed pyrolysis of scrap tires was studied in order to identify the influence of catalysts on gas composition during the main thermal range of the decomposition process. The aim is related to gas fraction optimization in terms of yield, composition, and distribution during the pyrolysis process. This is an original work using for the first time powder catalysts (MgO, Al2O3, CaCO3, and zeolite ZSM-5) uniformly distributed on a single layer of oyster shells (OSs) particles. The catalyst/tires mass ratio was kept for all the tests at 1/30. Depending on used catalyst, pyrolysis products yields ranged from 39 to 42 wt.% for char, from 26 to 38 wt.% for oils, and from 16 to 30 wt.% for gas. Compared to the thermal pyrolysis, it was found that the liquid yield increases in the presence of MgO/OS, while the use of Al2O3/OS decreases it significantly. The gas yield grows in the presence of Al2O3/OS ranging from 24.6 wt.% (thermal pyrolysis) to 30.6 wt.%. On the other hand, ZSM-5/OS and CaCO3/OS did not bring significant changes in products yield, but there are considerable influences on the evolution of gas composition during the tires decomposition. Also, two important advantages of using these new catalytic systems are identified. These relate to the formation of gaseous species throughout the waste decomposition, thus harmonizing the calorific value for the entire thermal range, and the disappearance of heavy molecules in liquid fractions, simplifying or canceling further upgrading processes.

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The treatment and disposal of tyres from vehicles has long been of considerable environmental importance. Studies have been undertaken to reduce their environmental impact. In this study, an alternative gas was produced from automobile tyre wastes by the means of a controlled pyrolysis. To do so, a novel catalytic system was designed with the aim of increasing the rate of conversion and improving the quality of the pyrolysis products. This work aimed also to reduce the severity of the overall reactions, by using powder catalysts (MgO, Al2O3, CaCO3, and zeolite ZSM-5) uniformly distributed on two layers of oyster shells (OS) particles. The catalyst/tyres mass ratio was kept for all the tests at 1/30. The pyrolysis reactor was maintained at 500 degrees C and the influence of each catalyst and of the number of shell beds (0, 1 or 2), on the yield and composition of the derived products, was examined. The gas yields could contribute by 1.2% of total consumption in Tunisia. Furthermore, some combinations could upgrade the derived gas and made it possible to use it as such or with the minimum of post-treatment. It was found that, with the use of supported catalyst, the gas produced is 45% greater compared to classical thermal pyrolysis. The Heating value of the produced gas was also improved by the use of supported catalysts; it was found 16% greater with the use of Al2O3/OS compared to non-catalytic pyrolysis. When compared to the gas obtained from only one catalytic supported bed, the sulfur content was reduced by 80% with the use of CaCO3/OS on two catalytic beds. (C) 2017 Elsevier Ltd. All rights reserved.

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In this article, correlation between the influence of catalysts on waste tires pyrolysis at. small- and laboratory-scale installation are highlighted. Kinetic and thermodynamic parameters of tires rubber thermochemical tranformations were evaluated using thermogravimetric analyses (TGA). For that purpose, Zeolite (ZSM-5), alumina (Al2O3, calcium carbonate (CaCO3, and magnesium oxide (MgO) were used as catalyst. It was found that all catalysts induce a delayed onset of pyrolytic process and MgO and. CaCO(3 )significantly reduced the activation energy (E-a from 246.89 kJ.mole(-1) (thermal pyrolysis) to 121.82 and 128.34 kJ.mole(-1), respectively. At laboratory scale, a fixed-bed. reactor was used to distinguish how the contact manner between tires and catalysts influences the yield of pyrolysis products as well as the gas quality. It. was proved that CaCO3 and Al2O3 are the most suitable catalysis for increasing the gas fraction, while the MgO promotes the formation of liquid fraction. (C) 2017 American Institute of Chemical Engineers.

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Evaluation of funded research, by measuring the outcomes of the grants publications, journals, and citations is not always done comparatively and publicised. Bibliometric indicators were employed and applied to the 2009-2014 publications authored by academicians funded by European research grants that are indexed in the Web of Science. Citation based approaches, such as the h-index or the impact factor, have been widely used to evaluate researchers or journals. In this study we use the aforementioned H-index to evaluate the funded research grants and to provide a ranking in terms of the most successful ones. The ranking results can be used by evaluators in determining how successful an applicant has potential to be, but also by researchers to choose their publication outlets, or to pursue future collaborations.

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The paper deals with the cellulase-mediated hydrolysis applied to several residual biomass resulting after extraction of biologically active principles from three medicinal plants: Melissa officinalis L., Melilotus officinalis L., Viola tricolor L. The yield of hydrolysis to hexoses was determined based on the amount of free glucose in the reaction mixture identified by spectrophotometric analysis, and total conversion of biomass residues was calculated. It was found that biomass resulted from Viola tricolor L. exhibits best glucose amount (10.35%) after 1 h of enzymatic hydrolysis, while that sourced from Melissa officinalis L. gives the highest total conversion of solid biomass (82.13%).

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The aim of this study was to develop a new variant of membranes based on collagen (COL), chitosan (CHI) and alkaline phosphatase (ALP) immobilized and cross-linking with glutaraldehyde (GA) at different concentrations. The biodegradation in the presence of collagenase was investigated. Biocompatibility was evaluated by MTT assay using a mouse fibroblast cell culture type NCTC (clone 929). Non-cross-linked samples were biocompatible and membranes cross-linked with low concentrations of GA (0.04, 0.08%) were also biocompatible. However, high concentrations of GA lead to a decreased biocompatibility. The adsorption behaviour of Ca2+ ions to all membranes were evaluated using the Freundlich isotherms. Haemolytic studies were performed in order to consider their applications in biomineralization process. By the addition of collagen and ALP to chitosan, the haemolytic index decreases, the COL-CHI-ALP membrane being in the non-haemolytic domain, while the COL-CHI-ALP-GA membrane has a haemolytic index greater than 2, and is slightly haemolytic.

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The paper presents a method for elaboration and characterization some chitosan-gelatine membranes with different collagen gelatine mass ratio, cross-linked with glutaraldehyde (GA) and coupled with extract plants. The aqueous extracts obtained from these plants were analyzed in terms of biologically active substances content (amino acids, polyphenols and phytosterols). The investigation for all obtained membranes involves: SEM microscopy, porosity, degradation test, contact angles measurement, hemolisys and antibacterian index determination.

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There is much interest in producing hydrogen from various materials, including rubbery wastes to help in the fulfilment of the predicted hydrogen economy of the future. In this paper thermal and catalyzed cracking processes have been investigated for their suitability in producing gaseous compounds during thermochemical decomposition of polymer-based materials. Hydrogen and hydrogen-carriers production through rubbery wastes cracking was carried out into a laboratory bench scale installation using a fixed bed reaction system. Experiments were conducted at 500 degrees C with a catalyst/waste ratio of 1/30. Catalysts influences on rubber decomposition were characterized using a variety of methods, including thermogravimetric analysis (TGA). The results indicated that the gas yield varied from 17 to 31 wt.% with addition of different catalysts. The potential of H-2 production was significantly increased from 14 to 32 wt.% by using MgO-based catalytic bed. Moreover, it was found that the higher heating value (HHV) of gases varied from 10 to 44 MJ/Nm(3), and the use of catalysts led to an increasing HHV especially in the first stage of cracking (250-350 degrees C). This work highlights the evolution of hydrogen and hydrogen-carriers during thermal and catalyzed cracking, too.

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In this paper both kinetic and thermodynamic parameters of thermochemical transformation of waste tires are evaluated by using thermogravimetric analysis (TGA). For rubber thermochemical decomposition, individually and in the presence of other tires components, some kinetic and thermodynamic parameters such as energy of activation (Ea), frequency factor (A), reaction enthalpy (Delta H), entropy (Delta S) and free energy (Delta G) have been calculated by using the integration method. The experimental data was used to highlight the influence of textile and metal tire compounds and provided worthy and substantive information on the issues to conduct and manage thermochemical process at larger scale in order to maximize the interest product yield. Kinetic parameters values show that tested materials exhibit different thermal degradation patterns during pyrolysis process at different heating rates. Two distinct areas of weight loss and a shift of thermal degradation peaks at higher temperatures and increasing heating rate have been identified. Also, it was established that both individual fiber and metal induce an important decreasing in Ea and Delta H values during tire rubber pyrolysis.

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In this paper the products obtained through thermochemical processing of several polymer-based wastes are characterised. The influence of chemical composition of raw materials on the characteristics of obtained products has been investigated by using fixed bed reactor. The aim of this work is to identify the best use of products recovered after pyrolysis of plastic wastes collected from chemical and biochemical laboratories. This work is developed in a laboratory bench installation design to perform O-2-free processing at atmospheric pressure. The process parameters such as pyrolysis temperature and adapted heating rate have been determined through the transposition of thermal and kinetic information provided by thermogravimetric analysis (TGA). Gas-chromatography techniques have been used to identify the chemical composition of gases (GC/TCD) and liquids (GC/FID-MS). It was established that polymer wastes can led to a valuable liquid products, with encouraging energetic properties that allow their blending with fuels currently used without altering the performances of burning devices.

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The paper is focused on elaboration and physical chemical and biological characterization of new membranes based on chitosan and gelatine. The membranes were prepared using two gels chitosan and gelatin, in molar ratio 1:1 and 1:3. The surface characterization includes scaning electronic microscopy (SEM), water absorbtion, and determination of contact angles. As biological tests hemolysis and biodegradation were performed.

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Thinking on environmental hazards, images of chemicals in waters, or air pollution coming out of industrial furnaces are most often seen. There are some hazards that are overlooked and one of them is scrap tires. Without a good management, scrap tires treatment can threaten not only our environment, but the public health as well. For instant, run-off from scrap tire fires can contaminate groundwater and surface water, and scrap tire sites are an ideal habitat for the breeding of insects carrying disease. In this paper we present an experimental approach on understanding and managing the environmental hazards of co-products resulted during energy recovery processes applied on scrap tyres. As tyre combustion faces serious problems related to harmful emissions, pyrolysis appears as a process that allows the management of toxic compounds. The experimental data were used to highlight the influence of textile and metal tyre compounds and provided worthy and substantive information on the issues to conduct and manage the thermochemical process in order to maximize the interest product yield. Thus, for the reactions occurs during pyrolysis and combustion of tyres organic matters the main intensive degradation thermal ranges have been established. The work was carried out by coupling thermogravimetric analysis (TGA) of tyre samples with bench scale reactor in order to identify the relationships between thermochemical behaviour and products distribution. TGA results afford the study of the kinetics parameters while the laboratory facilities allow the comprehension of tyres behaviours in real conditions. The processing temperature was limited at 700 degrees C and the measures focused on the mass balance determination and gaseous products analysis. It was found that the three obtained products have a good energetic potential: the solid (20-32 MJ/kg), the liquid (41-43 MJ/kg) and the gas (32-36 MJ/m3). Nevertheless, the liquid need to be upgrading in order to be used as Diesel-like fuel and gases should be treated to remove sulphur compounds. With this purpose some catalysts, known for their ability to increase gaseous fraction have been studied in TGA and an important shift of degradation peaks was identified and discussed.

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In this paper, the evolution in thermochemical behaviours of hospital plastic wastes and changes in chemical composition and characteristics of pyrolysis liquid products have been investigated by using different fixed bed reactor scales. The main objective is to identify the critical technical parameters enabling thermochemical process adaptation in function of raw materials chemical structure, with the aim of maximising the yield of condensable fraction and optimising its energetic properties related to internal combustion engines. It is a step-by-step procedure using three reactor capacity levels, which allows various aspects approach of thermochemical process development from the evaluation of global reaction kinetic parameters to the measurement of physicochemical properties of the final pyrolysis products. In order to reduce the gas and solid fractions with corresponding increasing of condensable products, the transposition of thermal and kinetic information provided by thermogravimetric analysis (TGA) to larger reactors is used to control of process parameters. In this experimental work the mass of samples increases from 0.05 g in the thermogravimetric analyser to 600 g in the bench scale reactor. Gas-chromatography techniques have been used to identify the chemical composition of gases (GC/TCD) and liquids (GC/FID-MS). It was established that changing the reactor scale does not result in significant differences in pyrolysis product distribution, neither in gas composition. On the other hand, the aspect and the quality of condensable fraction display a high variability. Also, the energy contained in the final valuable pyrolysis product was compared with the energy demand during the thermochemical transformation in order to evaluate the energy efficiency of the process. (C) 2015 Elsevier Ltd. All rights reserved.

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The paper refers to a bioactive matrix in membrane shape, with a thickness of 0.5 - 1.0 mm, and consisting of gelatine, chitosan, and α-chymotrypsin, with or without addition of glutaraldehyde as a cross-linking agent. The bioproduct is a biomaterial with biomedical applications as biocompatible membrane with anti-inflammatory action due to coupling of the proteolytic enzyme. Bioproducts have complex implications in the treatment of traumatized tissue, accelerating the pus cleansing of infected wound, blood clots and other cellular debris, secretions liquefaction and cleansing of necrotic tissue, and also stimulating tissue regeneration and a faster healing of open infected wounds. In order to establish the influence of cross- linking process and membrane’s thickness on mechanical properties, ultrastructural studies were carried out on obtained biomaterials by electron microscopy analysis. To demonstrate the biological qualities of new enzymatic biomaterials, the membrane’s biological effect was analyzed in a cell culture model (mouse fibroblasts NCTC). © 2014 Vasile Goldis University Press.