Characteristics of Oxidative Storage Stability of Canola Fatty Acid Methyl Ester Stabilised with Antioxidants

The storage effects on the oxidation characteristics of fatty acid methyl ester of canola oil (CME) were investigated in this study.CME stabilised with two antioxidants, i.e.2,6-di-tert-bytyl-p-cresol (BHT) and 6,6-di-tert-butyl-2, 2'-methylendi-p-cresol (BPH), was stored at 20, 40 and 60°C.The oxidation stability data were measured by the Rancimat test method and it was found that both BHT and BPH addition increased the oxidation resistance of the CME. The results showed that when BPH or BHT was added at a concentration of 100 ppm, the oxidation induction period of the neat CME samples increased from 5.53 h to 6.93 hand 6.14 h, respectively. Comparing both antioxidants, BPH proved to be more effective in increasing the oxidation resistance when both antioxidants were added at the same concentration. Furthermore, the oxidation induction timedecreased linearly with the storage time. It was shown that the oxidation occurred rapidly in the first 8 weeks of storage. Later, a kinetic study was undertaken and first-order kinetics were applied to explain the oxidation characteristics of the CME added with antioxidants. This kinetic study focused on exploiting the activation energy values obtained from the Arrheniusequations. Also, the oxidation effects on other quality parameters, including acid value, peroxide value, kinematic viscosity, and water content, were examined

Stabilization of Empty Fruit Bunch derived Bio-oil using Solvents

The intention of this research was to select the ideal condition for accelerated aging of bio-oil and the consequences of additive in stabilizing the bio-oil. The bio-oil was produced from the catalytic pyrolysis of empty fruit bunch. The optimum reaction conditions applied to obtain the utmost bio-oil yield were 5 wt% of H-Y catalyst at reaction temperature of 500 °C and nitrogen flow rate of 100 ml/min. A 10 wt% of solvents including acetone, ethanol, and ethyl acetate were used to study the bio-oil’s stability. All the test samples were subjected to accelerated aging at temperature of 80 °C for 7 days. The properties of samples used as the indicator of aging were viscosity and water content. The effectiveness of solvents increased in the following order: acetone, ethyl acetate, and 95 vol% ethanol. Based on the result of Gas Chromatography-Mass Spectrometry (GC-MS), it could impede the chain of polymerization by converting the active units in the oligomer chain to inactive units. The solvent reacted to form low molecular weight products which resulted in lower viscosity and lessen the water content in bio-oil. Addition of 95 vol% ethanol also inhibited phase separation

Sähkökemiallisesti valmistetut molekyylimallitetut polymeerit epäpuhtauksien detektoinnissa

New electrochemical molecularly imprinted polymers (e-MIPs) for benzo(a)pyrene (BaP) based on vinylferrocene (VFc) as redox tracer directly integrated into binding cavities during polymerization with crosslinker are reported. Impacts on the BaP detection are discussed according to: 1) the addition or no of 4-vinylpyridine (4VP) as comonomer, 2) the use of ethylene glycol dimethacrylate (EDMA) or divinylbenzene (DVB) as crosslinker. After characterization, these new e-MIPs and their corresponding non-imprinted polymers (e-NIPs) were incorporated in carbon paste electrodes and measurements were carried out by square wave voltammetry. All analyses revealed that e-MIP based on VFc and EDMA is the best to detect the template, with an imprinting factor of 7.3 and a LOD of 0.93 mu mol/L of BaP.Peer reviewe

Stabilization of Empty Fruit Bunch derived Bio-oil using Solvents

The intention of this research was to select the ideal condition for accelerated aging of bio-oil and the consequences of additive in stabilizing the bio-oil. The bio-oil was produced from the catalytic pyrolysis of empty fruit bunch. The optimum reaction conditions applied to obtain the utmost bio-oil yield were 5 wt% of H-Y catalyst at reaction temperature of 500 °C and nitrogen flow rate of 100 ml/min. A 10 wt% of solvents including acetone, ethanol, and ethyl acetate were used to study the bio-oil’s stability. All the test samples were subjected to accelerated aging at temperature of 80 °C for 7 days. The properties of samples used as the indicator of aging were viscosity and water content. The effectiveness of solvents increased in the following order: acetone, ethyl acetate, and 95 vol% ethanol. Based on the result of Gas Chromatography-Mass Spectrometry (GC-MS), it could impede the chain of polymerization by converting the active units in the oligomer chain to inactive units. The solvent reacted to form low molecular weight products which resulted in lower viscosity and lessen the water content in bio-oil. Addition of 95 vol% ethanol also inhibited phase separation

Highly selective BSA imprinted polyacrylamide hydrogels facilitated by a metal-coding MIP approach

We report the fabrication of metal-coded molecularly imprinted polymers (MIPs) using hydrogel-based protein imprinting techniques. A Co(II) complex was prepared using (E)-2-((2 hydrazide-(4-vinylbenzyl) hydrazono)methyl)phenol; along with iron(III) chloroprotoporphyrin (Hemin), vinylferrocene (VFc), zinc (II) protoporphyrin (ZnPP) and protoporphyrin (PP), these complexes were introduced into the MIPs as co-monomers for metal-coding of non-metalloprotein imprints. Results indicate a 66% enhancement for bovine serum albumin (BSA) protein binding capacities (Q, mg/g) via metal-ion/ligand exchange properties within the metal-coded MIPs. Specifically, Co(II)-complex-based MIPs exhibited 92 ± 1% specific binding with Q values of 5.7 ± 0.45 mg BSA/g polymer and imprinting factors (IF) of 14.8 ± 1.9 (MIP/non-imprinted (NIP) control). The selectivity of our Co(II)-coded BSA MIPs were also tested using bovine haemoglobin (BHb), lysozyme (Lyz), and trypsin (Tryp). By evaluating imprinting factors (K), each of the latter proteins was found to have lower affinities in comparison to cognate BSA template. The hydrogels were further characterised by thermal analysis and differential scanning calorimetry (DSC) to assess optimum polymer composition

Development of an electrochemical molecularly imprinted polymer for the surveillance of organic micro pollutants in the water of Canal de Provence

La technique de l’impression moléculaire permettant d'obtenir des polymères hautement sélectifs est utiliséedans de nombreuses applications. Dans le cadre de cette thèse, cette technique est employée pour préparer despolymères spécifiques du benzo(a)pyrène (BaP) en vue d’une application capteur. L’introduction d’une sonderédox au sein même du réseau de polymère offre la possibilité d’une détection directe de la cible, par unetechnique électrochimique. Dans le domaine des MIPs, ce travail est le premier à décrire l’utilisation d’unmonomère participant à la formation du réseau tridimensionnel tout en apportant une propriété rédox. Lespolymères synthétisés par polymérisation par précipitation ont été caractérisés en termes de composition, destabilité thermique et de propriétés texturales. Les propriétés de rétention ont été évaluées en mode batch parHPLC-UV en présence de BaP et d'interférents de type hydrocarbures aromatiques polycycliques. Ces MIPsprésentent de bonnes propriétés d’adsorption vis-à-vis du BaP avec des facteurs d’empreinte supérieurs à 1montrant l’efficacité de l’impression. Ces propriétés sont conservées en présence d’une matière organique (seld’acide humique), mais également après plusieurs cycles d’utilisation. Les analyses électrochimiques ontdémontré que les propriétés électrochimiques de ces MIPs diffèrent selon la présence ou pas de la cible avecune limite de détection de 0,09 μM en BaP, ouvrant la porte à la réalisation de capteurs.Molecularly Imprinted Polymers show highly selective affinity towards the target molecule and are used inmany applications. In this context, the technology is used for preparing selective polymers for benzo(a)pyrene(BaP) with the aim of sensor fabrication. The addition of a redox tracer inside the polymer allows thepossibility of direct target detection by an electrochemical technique. In the MIP field, this work is the firstreporting the use of a functional monomer that not only participates in the creation of the polymer network butalso provides a redox property. The polymers synthesized using precipitation polymerization technique werecharacterized in terms of composition, thermal stability and textural properties. The adsorption properties wereevaluated in batch mode by HPLC-UV in the presence of BaP and interfering polycyclic aromatichydrocarbons. These MIPs show good adsorption behavior towards BaP with imprinting factors superior to 1showing the efficiency of the molecular imprinting. These properties were also preserved even in presence ofan organic matter (humic acid salt), and also after several uses. Finally, electrochemical analysis showed thatthese MIPs had a different electrochemical behavior depending on the presence or the absence of the targetwith a detection limit of 0.09 μM for BaP. The use of such electrochemical MIPs can thus be interestinglyconsidered in sensor devices

Développement de polymères à empreintes moléculaires électrochimiques pour la surveillance en micropolluants organiques des eaux dans les ouvrages du Canal de Provence

Molecularly Imprinted Polymers show highly selective affinity towards the target molecule and are used inmany applications. In this context, the technology is used for preparing selective polymers for benzo(a)pyrene(BaP) with the aim of sensor fabrication. The addition of a redox tracer inside the polymer allows thepossibility of direct target detection by an electrochemical technique. In the MIP field, this work is the firstreporting the use of a functional monomer that not only participates in the creation of the polymer network butalso provides a redox property. The polymers synthesized using precipitation polymerization technique werecharacterized in terms of composition, thermal stability and textural properties. The adsorption properties wereevaluated in batch mode by HPLC-UV in the presence of BaP and interfering polycyclic aromatichydrocarbons. These MIPs show good adsorption behavior towards BaP with imprinting factors superior to 1showing the efficiency of the molecular imprinting. These properties were also preserved even in presence ofan organic matter (humic acid salt), and also after several uses. Finally, electrochemical analysis showed thatthese MIPs had a different electrochemical behavior depending on the presence or the absence of the targetwith a detection limit of 0.09 μM for BaP. The use of such electrochemical MIPs can thus be interestinglyconsidered in sensor devices.La technique de l’impression moléculaire permettant d'obtenir des polymères hautement sélectifs est utiliséedans de nombreuses applications. Dans le cadre de cette thèse, cette technique est employée pour préparer despolymères spécifiques du benzo(a)pyrène (BaP) en vue d’une application capteur. L’introduction d’une sonderédox au sein même du réseau de polymère offre la possibilité d’une détection directe de la cible, par unetechnique électrochimique. Dans le domaine des MIPs, ce travail est le premier à décrire l’utilisation d’unmonomère participant à la formation du réseau tridimensionnel tout en apportant une propriété rédox. Lespolymères synthétisés par polymérisation par précipitation ont été caractérisés en termes de composition, destabilité thermique et de propriétés texturales. Les propriétés de rétention ont été évaluées en mode batch parHPLC-UV en présence de BaP et d'interférents de type hydrocarbures aromatiques polycycliques. Ces MIPsprésentent de bonnes propriétés d’adsorption vis-à-vis du BaP avec des facteurs d’empreinte supérieurs à 1montrant l’efficacité de l’impression. Ces propriétés sont conservées en présence d’une matière organique (seld’acide humique), mais également après plusieurs cycles d’utilisation. Les analyses électrochimiques ontdémontré que les propriétés électrochimiques de ces MIPs diffèrent selon la présence ou pas de la cible avecune limite de détection de 0,09 μM en BaP, ouvrant la porte à la réalisation de capteurs

Biomass Nanoporous Carbon-Supported Pd Catalysts for Partial Hydrogenation of Biodiesel: Effects of Surface Chemistry on Pd Particle Size and Catalytic Performance

Two types of cattail flower-derived nanoporous carbon (NPC), i.e., NPC activated with KOH and H3PO4, were produced and characterized using several techniques (e.g., Raman spectroscopy, nitrogen adsorption, and X-ray photoelectron spectroscopy). The influence of the carbon support characteristics on the particle sizes and chemical states of Pd in the synthesized Pd/NPC catalysts, which affect the catalytic activity and product selectivity, was analyzed. The surface chemistry properties of NPC were the main factors influencing the Pd particle size; by contrast, the textural properties did not significantly affect the size of the Pd particles on NPC supports. The use of Pd nanoparticles supported on the rich-functionalized surface carbons obtained by H3PO4 activation led to superior catalytic activity for the polyunsaturated fatty acid methyl ester (poly-FAME) hydrogenation, which could achieve 90% poly-FAME conversion and 84% selectivity towards monounsaturated FAME after a 45-min reaction time. This is due to the small Pd nanoparticle size and the high acidity of the catalysts, which are beneficial for the partial hydrogenation of poly-FAME in biodiesel. Conversely, the Pd nanoparticles supported on the high-surface-area carbon by KOH activation, with large Pd particle size and low acidity, required a longer reaction time to reach similar conversion and product selectivity levels

Fuzzy Multicriteria Decision-Making for Ranking Intercrop in Rubber Plantations under Social, Economic, and Environmental Criteria

Rubber price instability causes great economic problems for rubber plantation in Thailand. Intercropping is an alternative way for rubber farmers in problem-solving. In this paper, we established decision-making system for plant selection in rubber fields under social, economic, and environment criteria with the use of fuzzy multicriteria decision-making (FMCDM) to rank plant options. Firstly, we modified the traditional FMCDM by defuzzification with norm centroid and developed the fuzzifier maps the norm centroid to triangular fuzzy number (TFN). According to fuzzification, the final rating evaluation of plant options are determined by total utility values. Finally, ranking of the plant options is obtained. Our modifications provided an alternative decision-making process with softer computational capability compared with the traditional method. In addition to soft computing, data visualization and analysis of the possibility in each factors could be investigated. This decision-making system was implemented in Phang-Nga Province, Thailand. Its outputs assisted the rubber farmer in selecting suitable plants for cultivation. Pros and cons of each plant options and area-based approaches were easily seen by data visualizations. This decision-making system provided beneficial information which support precision developments for rubber farmer and government agencies