Ethylene Absorption Research Articles

The ethylene absorption spectrum between 6075 and 8050 cm-1: Empirical line list and rovibrational assignments

The highly congested absorption spectrum of ethylene (C2H4) is analyzed between 6075 and 8050 cm-1. In the 6200–8050 cm-1 range, a list of about 32,650 lines is retrieved from a room temperature spectrum recorded by Fourier transform spectroscopy (P = 15.72 mbar, L = 45 m). This dataset was merged with a set of about 3460 lines available in the literature in the region of the strong ν5+ν9 band near 6150 cm-1. In addition, two FTS spectra at 130 K provide complementary information in the 6020–6320 cm-1 range (about 7570 lines).Relying on the position and intensity agreements with a line list of 12C2H4 transitions calculated by the variational method, a total of 4090 transitions is assigned to eighteen bands, ten of them being newly reported. All the reported assignments are confirmed by Lower State Combination Difference (LSCD) relations i.e. all the upper states (1749 in total) have coinciding determinations of their energies through several transitions (up to 6). The obtained empirical energy values are given and compared to their variational counterpart. As an additional validation test of the lower state assignments, the room temperature intensities are extrapolated at 130 K and compared to their experimental values. Overall, a large fraction of the strong lines of the region is assigned and the total intensity of the assigned transitions represents 46 and 55% of the total variational and experimental intensities at 296 K, respectively. In the considered range, variational positions deviate from measurements by a few cm-1 and the total variational absorption is underestimated by 40 %.

Revamping Ethylene Absorption Utilizing Brick Ash in Packaging for Prolonging the Freshness of Banana Leaves

Revamping Ethylene Absorption Utilizing Brick Ash in Packaging for Prolonging the Freshness of Banana Leaves

Flexible waterborne polyurethane nanocomposite foams incorporated with halloysites as fresh-keeping packaging inserts for fresh fruits

Food losses due to the deterioration of fresh fruits and related economic problems can be prevented by the use of active food packaging materials. Here, waterborne polyurethane (WPU)/halloysite nanotube (HNT) nanocomposite foams with ethylene and moisture absorption properties are presented, which can be inserted into existing food packages as fresh-keeping packaging materials for the improvement of the shelf life of fruits. WPU with moisture absorption properties has been utilized as a carrier for HNTs, which have a large capacity to absorb ethylene gas, the plant hormone responsible for the ripening of climacteric fruits. HNTs were incorporated into WPUs during a foaming process, resulting in open-cell foams with average pore sizes of 316 µm and a density of 0.136 g/cc. The resulting WPU-HNT foams were shown to absorb moisture by 7 % when they were incubated in a closed container of 100 % relative humidity for 14 days. The WPU-HNT foams were also demonstrated to absorb 2.5 ppm of ethylene gas per gram of foam when kept in a sealed container injected with 90 ppm ethylene gas for 3 days. Tomatoes stored together with the nanocomposite foams in plastic boxes at 4 °C for 14 days presented significantly higher firmness values than the tomatoes stored without the foams. Similarly, bananas stored in polyethylene bags containing the nanocomposite foam remained firmer and free of brown spots for at least 2 days longer than the bananas stored without the nanocomposite foam. The WPU-HNT foams have a strong potential as low-cost, environmentally friendly food packaging inserts that can prevent spoilage of fruits.

Fabrication and properties of natural rubber/rice starch/activated carbon biocomposite-based packing foam sheets and their application to shelf life extension of ‘Hom Thong’ banana

Natural rubber (NR) and rice starch (RS) biocomposite-based packing foam sheets were successfully prepared by the Dunlop method, with activated carbon (AC) as a filler to enhance mechanical properties (and to absorb ethylene gas released by packaged bananas). The primary objective of this study was to examine the influences of activated carbon contents from 0 to 20 phr on physical, morphological, mechanical, and thermal properties of the biocomposite foams. With increasing AC content, the foam cell size, density, hardness, compression force deflection (CFD), compression set, tensile strength, elongation at break, tear strength and glass transition temperature (Tg) increased, while the number density of foam cells and rebound resilience decreased. However, the content of activated carbon did not affect the thermal stability. Furthermore, the developed biocomposite foam with 15 phr AC, which had the highest ethylene removal, was used to evaluate the ethylene absorption capacity and the quality of 'Hom Thong' bananas during 12 days of storage in terms of weight loss, pulp firmness, total soluble solids (TSS), physical appearance, and peel color, with comparison to a commercial foam and control. The biocomposite foam with 15 phr AC lowered the ambient ethylene levels considerably, hence delaying fruit ripening and decreasing chlorophyll degradation, TSS, and pulp firmness at 6 days of ambient storage. The proposed biocomposite foam shows potential for enhancing the postharvest storage stability of bananas and has great potential as packaging for other fresh fruit products.

Design and analysis of Hollow-core fiber with anti-resonant structure for Ethylene detection

An optical fiber for mid-infrared (mid-IR) guidance has long attracted great interest due to its wide range of applications especially in gas sensing. Ethylene gas is one of an important gas, which release from the fruit and flower, owing to their ripening process. Thus, the controlling and detection of ethylene gas is of interest for the storage and exportation of fruits and flowers. Gas detection using the hollow-core optical fiber (HCF) is a promising technique due to it intrinsic micro-channel structure that allows the gas to flow through the HCF for detection propose. Here, a hollow-core anti-resonant fiber (HC-ARF) is designed and optimized for mid-IR guidance for the purpose of ethylene detection. The HC-ARF includes 6 inner tubes which is optimized to achieve a low confinement loss at a wavelength of 3.2 µm (ethylene absorption wavelength). The simulation result shows that a confinement loss of 2 dB/m at the wavelength of 3.2 µm can be achieved when the fiber core diameter is 128 µm and the thickness and the diameter of inner tubes are 2 µm and 92 µm, respectively.

Mechanochemically Scaled-Up Alpha Cyclodextrin Nanosponges: Their Safety and Effectiveness as Ethylene Scavenger.

Aiming at the development of a greener ethylene removal alternative, the goal of this study was to scale up and ensure the safety of α-cyclodextrin nanosponges (α-CD-NS) for further use as ethylene scavengers. The solvent-free synthesis of α-CD-NS was successfully scaled up using α-cyclodextrin and N,N′-carbonyldiimidazole as cross-linkers (1:4 molar ratio) by means of mechanical alloying using a PM 100 ball mill by focusing on varying the rotation frequency, as determined by FTIR-ATR, X-ray diffraction, and TGA. α-CD-NS washing optimization was performed in water by monitoring the imidazole concentration in the washing solution through the validation of a fast and sensitive HPLC-DAD method. After 6 h at 40 °C, all imidazole was extracted, allowing a faster and less energy-dependent extraction. α-CD-NS absorbent capacity and porosity were also evaluated through BET isotherms and ethylene absorption experiments using α-CD-NS and commercially available absorbents (zeolite and bentonite) were performed by means of gas chromatography (GC) coupled to a flame ionization detector (FID). With a 93 µL h−1 kgadsorbent−1 ethylene removal capacity, α-CD-NS revealed the best ethylene scavenging activity when compared to the other absorbents, opening the doors for a safer, innovative, and eco-friendlier ethylene removal active packaging.

Standard Industries Holdings to Acquire Grace

The density, viscosity and absorption of ethane and ethylene were determined experimentally, as a function of temperature and at atmospheric pressure, in different imidazolium-based ionic liquids: 1-methyl-3-octylimidazolium bis(trifluoromethanesulfonyl)imide, [C1C8Im][NTf2], 1-methyl-3-(propyn-3-yl)imidazolium bis(trifluoromethanesulfonyl)imide [C1(C2H2CH)Im][NTf2], 1-(3-cyanopropyl)-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [C1C3CNIm][NTf2], 1-(3-cyanopropyl)-3-methylimidazolium dicyanamide [C1C3CNIm][DCA], 1-butyl-3-methylimidazolium dicyanamide, [C1C4Im][DCA] and 1-butyl-3-methylimidazolium methylphosphite [C1C4Im][C1HPO3]. The densities and viscosities of the ionic liquids studied are strongly dependent on the anion and, at 313 K, follow the order: [C1(C2H2CH)Im][NTf2] > [C1C3CNIm][NTf2] > [C1C3CNIm][DCA] > [C1C4Im][C1HO3] > [C1C4Im][DCA] and [C1C3CNIm][NTf2] > [C1C3CNIm][DCA] > [C1C4Im][C1HPO3] > [C1(C2H2CH)Im][NTf2] > [C1C4Im][DCA], respectively. The differences in the molecular structures of the ionic liquids allowed the identification of the influence of increasing the alkyl side chain of the cation, of the presence of unsaturated CC and CN bonds on the alkyl side chain of the cation and finally of a phosphite based anion on the selective absorption of ethane and ethylene. The solubility of ethylene is higher than that of ethane in the ionic liquids studied and varies from 18.41 × 10−3 in [C1C8Im][NTf2] at 303.17 K to 1.603 × 10−3 in [C1C4Im][DCA] at 343.61 K. The introduction of the different functional groups leads to a decrease on the gas absorption compared with that of [C1C8Im][NTf2] but to an increase of the ideal separation selectivity of ethane and ethylene.

Reducing Moringa Leaflet Abscission after Irradiation and during Shipping

Moringa (Moringa oleifera), also known as the pot herb drumstick or horseradish leaves, requires irradiation treatment for insect disinfestation before shipping to the west coast of the United States from Hawai’i. This irradiation treatment as well as packing and air shipment leads to leaflet abscission. To minimize this abscission, the shipper had been including frozen gel packs in the shipping carton. However, these packs are heavy and lead to chilling injury on the leaflets and the development of mold on the leaves adjacent to the gel pack. Holding and shipping the product at 12 °C negated the need for the frozen gel packs. Inclusion of a sachet of 1-methylcyclopropene in the carton significantly reduced leaflet abscission. Further reduction was obtained by the inclusion of an ethylene absorption sachet, thus helping to maintain the overall product quality and marketability.

Intensification of ethylene and ethane absorption in N-methyl-2-pyrrolidone (NMP) by adding silver nanoparticles

The absorption and solubility of pure ethane and ethylene gases were investigated in an experimental pressure decay setup, where a small amount of silver nanoparticles was added to pure N-methyl-2-pyrrolidone (NMP) solvent. All the experiments were performed at temperatures of 278.15, 298.15 and 328.15 K and different pressures (up to the gases dew points) as well as different concentrations of silver nanoparticles (0.05 and 0.1 g/l). The kinetic data of absorption, Henry’s law constants, heat of absorption, entropy, Gibbs free energy, and ideal selectivity were reported. Also, the effects of temperature, pressure, and nanoparticle concentration on the equilibrium results were evaluated. The absorption results revealed that the presence of small amounts of nanoparticles in the solvent intensified the absorption performance between 1.5–18 % for ethylene and 1–41 % for ethane. The results also showed that the solubility of ethylene in pure solvent and nanofluids was better than that of ethane. Increasing the nanosilver concentration up to 0.1 g/l resulted in reducing the absorption equilibrium time specially for ethylene/nanofluid experiments. Also, the ideal ethylene/ethane selectivity improved by increasing the nanoparticle concentration at the same temperature.

Preparation of novel nano–based films impregnated by potassium permanganate as ethylene scavengers: An optimization study

Potassium permanganate (KMnO4) is a dominant ethylene (C2H4)-scavenger extensively used in fresh horticultural commodities, mainly in climacteric fruit, to prolong their shelf life. This material has been traditionally utilized as a C2H4-permeable sachet for inclusion into packages of produces. New formulation strategies are required in polymeric materials to develop nanocomposites with ethylene scavenging potential, as well as good barrier and mechanical properties. This work involved preparation and optimization of novel interesting nanocomposites based on polyolefin elastomer (POE) comprising impregnated nanoparticles (nanosilica (NS) and nanoclay (NC)) with KMnO4 via the response surface methodology (RSM). Regression models were developed for water vapor permeability (WVP), ethylene absorbency (EA), and mechanical properties as a function of concentrations of independent variables (POE-g-MAH (0–3%), NS (0–1.5%), NC (0–2%)). According to Field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) analysis results, both NS and NC were fully dispersed in the POE matrix. The prepared nanocomposites demonstrated enhanced mechanical properties, larger EA, and lower WVP than neat POE film did. Ethylene absorption capacity increased at higher concentrations of impregnated nanoparticles due to their higher KMnO4 concentration. In addition, the optimized nanocomposite films were shown to extend the shelf life of bananas up to 15 days at ambient conditions.

Ethylene absorption in N-methyl-2-pyrrolidone/silver nano-solvent: Thermodynamics and kinetics study

The effect of presence of silver nanoparticles in pure N -methyl-2-pyrrolidone (NMP) solvent for ethylene gas absorption in an experimental pressure decaying setup has been investigated. All experiments were performed at temperatures of 278.15 K, 298.15 K and 328.15 K and different pressures (up to ethylene dew point) as well as different concentrations of silver nanoparticles (0.05 g·L −1 and 0.1 g·L −1 ). The kinetic data of absorption, Henry's law constants, and heat of absorption were calculated. Comparison of the pure solvent and the nanofluids absorption results revealed that the presence of small amounts of nanoparticles could improve the absorption performance between 1.5% - 18%. Finally, the effect of temperature, pressure, and nanoparticle concentration on the equilibrium results were investigated.

Experimental study and thermodynamic modelling of ethylene absorption in N-methyl-2-pyrrolidone (NMP)

Determining the solubility of gases in solvents and considering non-idealities at different operating conditions are essential to design a cost-effective and energy-efficient absorption process. In this work, using a lab-made set-up, solubility of ethylene in N-methyl-2-pyrrolidone (NMP) was measured at different temperatures (278.15, 298.15, and 328.15 K) and pressures up to 14 bar, and the kinetic and equilibrium data were obtained. Accordingly, Henry’s law constants are calculated at various temperatures. Then, thermodynamic modeling was accomplished by applying Peng-Robinson equation of state (PR-EOS) and Wilson activity coefficient model, and the binary interaction parameters were estimated. By the thermodynamic modeling, positive deviation from ideal behavior was apparently observed. Due to low absolute average deviation of < 7.7%, the correlated model was able to predict the ethylene solubility in NMP with a reliable accuracy.

Alkaline halloysite nanotubes/low density polyethylene nanocomposite films with increased ethylene absorption capacity: Applications in cherry tomato packaging

Halloysite nanotubes (HNTs) are hollow tubular clay nanoparticles used as nanofillers to remove or minimize the production of ethylene gas. The presence of ethylene gas leads to reduced shelf life in fruits and vegetables by accelerating postharvest softening and aging. Alkaline solution-treated HNTs have increased ethylene adsorption capacity due to an increased number of OH groups on the HNTs external surface. This study reports on the thermal, morphological, and mechanical properties of alkaline HNTs (ALK-HNTs) loaded into a low-density polyethylene (LDPE) matrix. Our results indicate that, although the mechanical properties of the LDPE matrix films were not improved with loading ALK-HNTs, the oxygen barrier property were improved and ethylene gas adsorption increased by 220 %. Cherry tomatoes packaged in a 3% ALK-HNTs/LDPE nanocomposite film and stored at 8 °C for 21 days showed a reduction in loss of firmness and weight by 17.0 % and 36.7 %, respectively.

Review on sensitive and selective ethylene detection methods for fruit ripening application

PurposeThis work encompasses the various laboratory-based and portable methods evolved in recent times for sensitive and selective detection of ethylene for fruit-ripening application. The role of ethylene in natural and artificial fruit ripening and the associated health hazards are well known. So there is a growing need for ethylene detection. This paper aims to highlight potential methods developed for ethylene detection by various researchers, including ours. Intense efforts by various researchers have been on since 2014 for societal benefits.Design/methodology/approachThe paper focuses on types of sensors, fabrication methods and signal conditioning circuits for ethylene detection in ppm levels for various applications. The authors have already designed, developed a laboratory-based set-up belonging to the electrochemical and optical methods for detection of ethylene.FindingsThe authors have developed a carbon nanotube (CNT)-based chemical sensor whose performance is higher than the reported sensor in terms of material, sensitivity and response, the sensor element being multi-walled carbon nanotube (MWCNT) in comparison to single-walled carbon nanotube (SWCNT). Also the authors have developed infrared (IR)-based physical sensor for the first time based on the strong IR absorption of ethylene at 10.6 µm. These methods have been compared with literature based on comparable parameters. The review highlights the potential possibilities for development of portable device for field applications.Originality/valueThe authors have reported new chemical and physical sensors for ethylene detection and quantification. It is demonstrated that it could be used for fruit-ripening applications A comparison of reported methods and potential opportunities is discussed.

Membrane Absorption of Ethylene from a Mixture with Ethane Using MDK-3 Composite Membranes

Separation of olefin/paraffin mixtures is an important problem. The use of a gas—liquid membrane contactor is an attractive alternative to traditional power-consuming cryogenic distillation methods. The paper deals with the separation of ethylene from its mixture with ethane (component ratio 19/81 vol %, respectively) using an aqueous silver nitrate solution as a selective ethylene absorbent in a flat-sheet lab-scale membrane module equipped with an MDK-3 commercial composite membrane with the selective layer based on silicone rubber. The effect of the absorbent and gas mixture feed linear velocities on the residual ethylene content of the mixture is considered. The thin selective layer of the membrane is shown to preserve high performance during long-term experimental run ensuring high mass-exchange characteristics and preventing the absorbent penetration into the porous structure of the membrane support.

Ethylene absorber (KMnO4) in postharvest quality of pinha (Anona squamosa L.)

The ripening pattern of the climacteric type of the pinha (Anona squamosa L.) limits its shelf life at room temperature, in addition, storage at low temperatures develops cold sores on the fruit. Thus, the association of conservation technologies is fundamental to reduce the losses in the post-harvest of this fruit, so it was aimed to evaluate sachets impregnated with potassium permanganate (KMnO4) associated with refrigeration in the control of ripening and preservation of quality. For this, pinhas were harvested at physiological maturity, packed in polystyrene styrofoam trays coated with PVC film with and without the presence of sachets containing 3 g of KMnO4 and stored at 13 ºC for 20 days. Every five days the fruit quality was evaluated as: weight loss, cracking index, firmness, external appearance, starch content, soluble solids, titratable acidity, pH, ratio SS/TA, coloring (Hue, Chroma and Luminosity) and cold damage. The absorption of ethylene by the KMnO4 sachet inside the packages preserved significantly (p&lt;0.05) the physical-chemical quality and the visual appearance of the fruits but did not influence the coloration (chroma and luminosity) and incidence of damage by cold in relation to its control at the end of the storage period. The packing of pinhas containing 3 g of KMnO4 is an alternative to delay ripening, prolong the shelf life without compromising the physical-chemical quality of the fruits.

Experimental Study of Ethylene Evaporites under Titan Conditions

Titan has an abundance of lakes and seas, as confirmed by Cassini. Major components of these liquid bodies include methane ($CH_4$) and ethane ($C_2H_6$); however, evidence indicates that minor components such as ethylene ($C_2H_4$) may also exist in the lakes. As the lake levels drop, 5 $\mu m$-bright deposits, resembling evaporite deposits on earth, are left behind. Here, we provide saturation values, evaporation rates, and constraints on ethylene evaporite formation by using a Titan simulation chamber capable of reproducing Titan surface conditions (89-94 K, 1.5 bar $N_2$). Experimental samples were analyzed using Fourier transform infrared spectroscopy, mass, and temperature readings. Ethylene evaporites form more quickly in a methane solvent than in an ethane solvent or in a mixture of methane/ethane. We measured an average evaporation rate of $(2.8 \pm 0.3) \times 10^{-4} kg \; m^{-2} \; s^{-1}$ for methane and an average upper limit evaporation rate of less than $5.5 \times 10^{-6} kg \; m^{-2} \; s^{-1}$ for ethane. Additionally, we observed red shifts in ethylene absorption bands at 1.630 and 2.121 $\mu m$ and the persistence of a methane band at 1.666 $\mu m$.

POSTHARVEST QUALITY AND CHILLING INJURY OF “SUCCARY” POMEGRANATES AS AFFECTED BY DIFFERENT PACKAGING TYPES

Fully ripe 'Succary' pomegranate fruits were harvested from a private orchard in Ismailia, Egypt in 2015 &amp; 2016 seasons. The fruits were packed in: 1- freely packed fruits (control) 2- sealed fresh bags of high ethylene absorption (HEA) 3- perforated polyethylene )PPE( 4- polyethylene (PE) film (stretchable cling film) 5- commercial PVC (poly vinyl chloride) pages. All packaging treatments were stored at 5 ºC and 90 – 95% RH for 12 weeks. Samples were taken every 2 weeks followed by 4 days at 20˚C. Fruit weight (g) rind thickness (mm), aril /fruit (%), juice content %, juice colour, SSC, acidity%, total sugars%, total phenols% and vitamin C were evaluated at harvest time. Chilling injury of the fruit was reduced by all packaging types. Changes in acidity, and SSC of the packed fruits were lower than that of freely packed fruits (control) during storage period. Cold storage at 5 °C with packaging treatments would be the best for preserving the freshness and vitamin C, increasing antioxidant activity, reducing chilling injury and maintaining fruit quality. Consequently, the fruits were more commercially acceptable.

Design of Industrial Water Cooled Chiller for Recycle Cyclohexane in Polyethylene Plant

The research was aimed at providing water for cooling recycled cyclohexane in polyethylene plant to 15°C. This research could be redounding to the benefit of polyethylene plants that are using solution based polymerization technique. A chiller unit of 630 T, which has compressor power input of 378.33 kW and can provide chilled water capable of cooling recycle cyclohexane to 15°C, was designed using Aspen Hysys version 7.1. Four different refrigerants were tested to know the best fit refrigerant for the design and the best among them was R134a. The designed chiller has a coefficient of performance of 6.3 and a capacity greater than that of the defective chiller (550 TR). Unlike the defective chiller, with the increased cooling capacity and corresponding increase in compressor power from 296 kW to 378.6 kW, it could discharge chilled water capable of cooling recycle cyclohexane from 38°C to 15°C without tripping of the unit. With this design, ethylene absorption rate could increase to 40 T/h. Evaporator and condenser were designed and duties were 2166.39 KJ/sec and 2544.72 KJ/sec respectively. A thermostatic expansion valve with flow coefficient of 46.17 gpm was designed. The designed suction and discharge pressure were 414 kpa and 1053 kpa respectively while condenser temperature of 40°C was used for the design. The cooling of recycle cyclohexane from 38°C to 15°C using the chilled water supplied by the designed chiller was simulated using Aspen Hysys.

Investigating Thermal and Surface Properties of Low‐Density Polyethylene/Nanoperlite Nanocomposites for Packaging Applications

Nanocomposites films based on low‐density polyethylene (LDPE) and different compositions of treated and untreated nanoperlite were prepared via melt mixing of the ingredients on a corotating twin‐screw extruder and then film blowing the nanocomposites. The physical dispersion of the nanocomposites is confirmed using Fourier transform infrared‐attenuated total reflectance (FTIR‐ATR) method. According to the thermal studies, the nanocomposites with untreated nanoperlite showing higher melting temperature and crystallinity, while their thermal stability is lower than nanocomposites with treated nanoperlite. The thermal and FTIR‐ATR studies also revealed the ethylene absorption of the nanocomposites. According to the surface energy results, the treatment of the nanoparticles completely changes the surface behavior and hydrophobicity of the films. Finally, peel color index and field study observations showed that increase in nanoperlite will increase the shelf life of the fruits; however, the nanocomposite with 6% untreated nanoperlite is the best choice for the packaging applications. POLYM. COMPOS., 40:2929–2937, 2019. © 2018 Society of Plastics Engineers