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Potato starch can be widely expected to serve as the new alternative packaging material in food preservation in recent years, due to its excellent properties. The endogenous phosphate groups of potato starch can be ionically bonded to the surrounding polar hydroxyl groups. However, the research on potato starch is limited by the high water absorption and low gas resistance. Fortunately, the low-temperature plasma technology can be used to modify the potato starch for easy oxidation, cross-linking, depolymerization, the increase or decrease of hydrophilicity, and the introduction of functional groups, particularly for the better surface properties of potato starch. Cinnamon Essential Oil (CEO) can be added to the potato starch film as a bacteriostatic agent, in order to inhibit the activity of pathogenic, as well as decaying fungi and bacteria for better food safety. Nano-silica (SBA-15) can be used to wrap the Cinnamon Essential Oil (CEO) for slow and controlled release. The surface of SBA-15 often contains a large number of unsaturated residual bonds and weak acidic free Si-OH in the different bonding states. However, a large specific surface area of the SBA-15 is easy to agglomerate in the aqueous solution. The carboxyl group on the surface of modified potato starch is the hydrogen bond with the polar hydroxyl group on the surface of SBA-15. It is very necessary to improve the dispersion of CEO-SBA-15 in the potato starch film, together with the physical properties of the composite film. In this study, the modified CEO-SBA-15/potato starch film was prepared by low-temperature plasma modification. The investigation factors were taken as the plasma treatment time and the dosage of potato starch, glycerol, and CEO-SBA-15. The performance of the composite film was then optimized and screened by the single factor, orthogonal, and verification experiment. The optimized composite films were characterized by the surface morphology (Scanning Electron Microscope, SEM), phase change (X-Ray Diffraction spectroscopy, XRD), as well as the chemical bond and functional group (Fourier Transform Infrared Spectroscopy, FTIR). A systematic evaluation was performed on the oxygen and water vapor permeability, swelling degree, water solubility, opacity, tensile strength, UV spectrum, and Thermogravimetric analysis (TG). The results showed that the duration was 6 min for the optimum factor ratio in the preparation of modified potato composite film using the low-temperature plasma technology. The dosages of potato starch, glycerol, and CEO-SBA-15 were 5, 1.5, and 0.5 g/100 mL, respectively. The SEM images showed that there were circular depressions on the surface of plasma-treated potato starch. The CEO-SBA-15 was evenly dispersed in the composite film prepared by the plasma-treated potato starch solution. The XRD and FTIR showed that the plasma-modified potato starch formed a strong hydrogen bond with the CEO-SBA-15. The plasma-modified potato starch shared the formation of an oxidized carboxyl group and the reduction of a hydroxyl group. Ultraviolet (UV) spectrum analysis showed that the plasma-treated composite film presented better UV resistance and light transmittance. The TG showed that the plasma-modified potato starch composite film had better thermal stability. In addition, the physical properties were greatly improved in the potato starch composite film prepared by the plasma system. The oxygen permeability, water vapor permeability, and swelling degree of the composite film were reduced by 4.32 g(m²·h), 7.48 g(m²·h), 79.15%, respectively, while the tensile strength of the composite film increased by 2.9 MPa, compared with the unmodified composite film. The finding can provide a strong reference to better protect the food contents from external factors and mechanical damage. [ABSTRACT FROM AUTHOR]

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As a renewable energy source that is expected to replace fossil fuels, biomass energy is attracting more and more attention. Pyrolysis is considered to be one of the cutting-edge technologies for converting biomass energy into high value-added products such as gas, tar and biochar, but because of the low energy density of biomass energy, it needs to be pretreated prior to pyrolysis reaction to improve the quality of the products. The products are often regulated by adding catalysts during biomass pyrolysis, among which alkali metal salt catalysts are widely concerned due to their advantages of high efficiency and low cost. In view of the serious air pollution caused by corn stover burning in the northeast of China recently, in this work corn stover was obtained, and the influence of Na2CO3 and NaCl on the pyrolysis characteristics and gaseous products releasing kinetics were studied in a micro-fluidized bed reactor coupled with mass spectrometer (MFBR-MS), with the conditions of with and without Na2CO3 or NaCl addition at 550, 600, 650, 700 and 750 ℃, respectively. The purpose of this work was to grasp the catalytic process of Na2CO3 and NaCl on the gaseous products during corn stover pyrolysis and to better play its catalytic role to obtain the products desired. Besides, in order to obtain the reaction kinetic parameters of different gaseous products accurately, the kinetic parameters of single-component gas were calculated by using the Isothermal Model Fitting Method. The results showed that under the same temperature, the conversion rates of CO, CO2 and CH4 during corn stover pyrolysis with Na2CO3 addition increased significantly, which indicated that Na2CO3 significantly promoted the generation of carbonaceous gaseous products. However, the conversion rate of H2 during corn stover pyrolysis with NaCl addition increased significantly. When the temperature increased, all the amount of each gas phase product increased, especially the CO amount increasing most. Meanwhile, each gas phase product tended to release simultaneously, indicating that the Na-containing salts could promote the reaction. Among them, the releasing rates of CO, CO2 and CH4 all increased with Na2CO3 addition, indicating that it promoted the generation of carbonaceous gaseous products. Besides, the releasing rate of H2 increased with NaCl addition, indicating that NaCl promoted the generation of H2. The results of activation energies of different gas phase products during corn stover pyrolysis showed that the activation energies for different gaseous products were different, and the activation energies for CO and CO2 were generally smaller than that of CH4 and H2, which indicated that CO and CO2 were easier to generate than CH4 and H2. For CO and CO2, the addition of Na2CO3 and NaCl generally reduced the activation energies. The above results showed that during the corn straw pyrolysis, the conversion rates of carbonaceous gaseous products or H2 could increase with Na2CO3 or NaCl addition significantly. We hope the method of converting corn stover into combustible gases via pyrolysis discussed here could provide a method for the treatment of corn stover. [ABSTRACT FROM AUTHOR]