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In this study, the effects of salicylic acid to antioxidative activity and photosynthetic characteristics in waterlogging stress of two peony cultivars (‘Fengdanbai’ and ‘Mingxing’) were investigated. 4-year-old peony grown in different levels of waterlogging stress and then different concentration prepared SA (0.0, 0.1, 0.5 and 1.0 mmol L–1) sprayed on fresh leaves of peony. The antioxidative enzymes activities include superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT), chlorophyll content, relative conductivity and MDA content were measured in leaves about different waterlogging treatment, the photosynthetic characteristics were also measured using photosynthetic measurement system. The results showed that waterlogging stress decreased the chlorophyll content in all peony cultivars leaves, but with SA treatment can inhibit the decrease of chlorophyll content. Relative conductivity increased as the extension of waterlogging time in two cultivars. SA treatment could effectively inhibit the increase of relative conductivity, and 0.5 mmol L–1 of SA was the most suitable concentration. SOD, POD, CAT activity increased first and then decreased in different waterlogging condition, SA significantly increased the activity of various enzymes. MDA content was increase as the expansion of waterlogging time in two cultivars. SA inhibits the increase of MDA content. Of all concentration of SA, 0.5 mmol L–1 was the best concentration to inhibit the waterlogging stress. For the photosynthetic characteristics, the net assimilation rate (Pn), stomatal conductance (Gs), transpiration rate (Tr) and intercellular CO2 (Ci) were decreased under different waterlogging condition. SA treatment can increase Pn, Gs, Tr and Ci of peony.

Semisteel, the main by-product of titania slag-smelting process of ilmenite with an electric furnace, cannot be widely used in the steel-making process because of its high sulfur and low carbon contents. Hoganas and water atomization processes are currently the major iron powder production techniques in China, but both have obvious drawbacks. A novel and clean iron powder production process is suggested to enhance the added value of semisteel, improve the production efficiency, and reduce the energy and water consumption. A circle of water curtain was set around a rotary cup atomizer. The iron powders and hot vapor produced in this new process can be applied in the reducing and leaching steps of sulfate process, respectively, which is propitious to cut down the manufacturing cost of titanium dioxide and realize optimized resource allocation and highly effective utilization. The effect of rotating speed on the obtained iron granules was investigated. Result shows that the median diameter of the obtained granules decreases with the increase in rotating speed and varies from 0.55 mm to 0.49 mm when the rotating speed is in the range of 600 rpm to 1000 rpm. The atomization mechanism of the molten semisteel was calculated to follow the ligament formation mode under the given experimental conditions. The obtained iron granules were analyzed by X-ray diffraction and scanning electron microscopy. The surfaces of the iron granules are smooth and are covered with a layer of iron oxides, including Fe3O4, FeO, and relatively small amounts of Fe2O3. Reduction experiments in hydrogen atmosphere at 1173 K (900 °C) were conducted to remove the iron oxides on the surfaces of the iron granules. The oxidation degree of iron powders decreases from 14.06% to 4.33% when the particle size varies from 0.3–0.35 mm to 0.6–0.65 mm. After reduction, the iron powders have dramatically rough surfaces and large specific surface areas, which benefit their reaction as reducing agents in the sulfate process.

The study specifically focused on the effect of different promoter characteristics and interactions between Ni-Ce, Ni-Fe, and Ni-Mg on the physicochemical properties of Ni/HZSM-5 catalyst. The results revealed that promoter characteristics are important when determining the form of nickel atomic species, structural properties and catalytic abilities of catalysts. The Fe-modified Ni/ZSM-5 catalyst has the most effective catalyst for hydrogen-rich gas production with the highest gaseous efficiency of 63.4 wt.%, gas yield of 118.6 mL/g toluene, H2 yield of 53.4 mL/g toluene at 800 °C pyrolysis for 1 hour. However, the stability of catalysts improved by incorporating CeO2, the H2 yield was lower (40.3 mL/g). Ni-Mg/HZSM-5 catalyst was slightly less stable. The smaller crystal particles (3.1 nm), high surface area (219.5 m2/g), and sufficient loading (4 wt.%) for Ni-Fe catalysts provide efficient active sites and promote the process for pyrolysis biomass tar. Catalyst’s deactivation is associated with char deposition.

This study investigated methods to optimize the process conditions for preparing levulinic acid (LA) using magnetic ferric oxide/SO42- biomass-based solid acid, to catalyze pyrolysis of corn straw using response surface methodology (RSM). The measured parameters were quality of liquid-solid ratio (QLSR), catalyst dosage (CDe), hydrolysis temperature (HT) and hydrolyzation duration (HD). The mathematical model of the quadratic polynomial of LA had a P-value less than 0.005, and the loss of quasi P-value was less than 0.01; the R2 value of 0.9969 indicates that the model was highly significant. The coefficient of variation was 3.02% (

Wheat straw, a typical lignocellulosic biomass, is difficult to be liquefied because of its complex structure, which limits its further conversion to valuable products. Ionic liquid can dissolve the cellulose, which can destroy the connection of biomass components. Ionic liquids, [BMIM][HSO4], [BMIM][Cl], and [HSO3-BMIM][HSO4], were used in the liquefaction of wheat straw to produce ethyl levulinate (EL) in a one-pot reaction under mild conditions in ethanol, which served as both solvent and reactant. The highest conversion rate, 85.50%, was obtained following reaction at 200 °C for 60 min using the acidic ionic liquid 1-methyl-3-(4-sulfobutyl) imidazole bisulphate as the catalyst. Under optimal conditions, ethyl levulinate was obtained with a yield of 16.23% and its content in the liquid products was 28.11%. Without the acidic ionic liquid catalyst, the conversion rate of wheat straw and the yield of ethyl levulinate were only 22.33% and 6.23%, respectively. Of the catalysts evaluated, [HSO3-BMIM][HSO4] was the most effective, and its recovery rate was 64.71%. This study provides a theoretical basis for the development and utilisation of low-corrosion and environment-friendly catalysts for liquefaction processes for the preparation of high-grade chemicals.

Four kinds of carbon-based magnetic solid acid catalysts (CBMSACs) were prepared from rice husk, wood chips, peanut shells, and corn straw. The structure was investigated via x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), elemental Analysis (EA), scanning/transmission electron microscope (SEM/TEM), and BET analyses. The catalysts were used to hydrolyze cellulose, and the hydrolysis efficiencies were determined. The catalysts were all comprised of a disordered carbon structure with random polycyclic aromatic hydrocarbons similar to graphite layers. This structure had a large number of -SO3H groups and the alkyl side chain, which increased the electron cloud density of the carbon carrier, relative to the other catalysts; this was advantageous to the adhesion of the -SO3H group to increase the activity of catalysts. The product also contained a large number of magnetic particles, making it easy to separate the catalysts from the reaction residue. The properties of the catalyst derived from corn straw as the carbon source appeared to be the best. Although it could be further recycled many times, the catalyst activity decreased due to the loss of -SO3H groups. At the same time, the catalyst had a high specific surface area of 755 m2/g.

Semisteel, the main by-product of titania slag smelting process of ilmenite concentrate with an electric furnace, is of high sulphur and low carbon. As a result, the semisteel cannot be widely used in the steeling process and the market value is relatively low. In order to enhance the added value of semisteel, a novel process which was based on a rotary disc atomizer was suggested on semisteel to produce iron powders in the present study. The oxidation degree of the obtained iron granules was studied by thermogravimetric analysis (TG) in the mixture gas of nitrogen and hydrogen.

Fifty different kinds of wheat from 10 provinces in China were chosen as samples to be milled into flour. Dumpling wrappers were made from the flour and their texture qualities and rheological properties, disulfide content, sulfhydryl content, and gluten secondary structure were determined. The web structure formed by the gluten was observed under scanning electron microscopy. These results showed that the flour’s rheological properties, apart from extensibility, were significantly correlated with several aspects of the texture of the dumpling wrapper, and the degree of softening showed negative correlations, most closely with the texture quality of the dumpling wrapper. Disulfide played an important role in forming the gluten web, its content showing significant correlations with the rheological properties of the flour and the texture quality of the dumpling wrapper. The disulfide content in gluten was positively correlated with the hardness and quality of the cooked product; the sulfhydryl content showe...

Polyethylene terephthalate (PET) contributes to majority of the global plastics wastes generated and its lack of sustainable recycling calls for the development of pathways for this waste transformation to energy and chemicals extraction that will help avoid landfilling of this waste. In this paper, CO2 assisted gasification of PET was investigated at 800 °C to 950 °C using a fixed bed reactor to understand the feasibility of this pathway for PET waste management. Evolutionary behavior of the yields of H2, CO, CH4, total C2-C3 gases and total syngas from fixed bed reactor were investigated to understand the influence of temperature on isothermal conversion. Gasification composition and total accumulative syngas rate were also calculated and compared. Solid residues from gasification were analyzed for morphological characteristics and CO2 consumption. Evolution rate and yield of H2, CO, CH4 and total syngas from fixed bed reactor changed with increase in reaction time and temperature. CO yields increased from 0.5 to 0.9 g/g (gas mass yield per unit mass of PET), which accounted for 89.9 to 95.2 wt% of the total syngas yield with increase in temperature from 800 °C to 950 °C. The CO mole fraction accounted for about 73.3 to 79.4 vol% of their total syngas at the different temperatures examined. Brunauer-Emmett-Teller (BET) surface area of solid resides from CO2 gasification increased from 434 to 936 m2/g with increase in temperature. These results showed thermal decomposition behavior under CO2 gasification influenced the char structure and the effect became more pronounced with increase in temperature. CO2 gasification of each mass unit of PET provided with the capability to convert about 0.1 to 0.7 mass unit of CO2 into valuable syngas (a precursor for various value-added products) which reveals the synergistic possibility of PET waste management along with CO2 utilization in this process of energy and value-added product recovery.

In recent years, a new process of “direct reduction-electric furnace smelting separation” has been put forward and developed for recovering the iron, vanadium, titanium and chromium to make full use of the chromium-bearing vanadium titanium magnetite. In the present work, FactSage, one of the most frequently-used thermodynamic calculation software, was used to calculate the migration of Fe, V, Cr and Ti with different nC/nO (mole ratio of carbon and oxygen). The calculation results indicate that the recoveries of Fe, V and Cr increase with increasing nC/nO and temperature respectively. In addition, the recoveries of Fe, V and Cr are up to 90% when the nC/nO value is more than 1.15.

In order to make full use of the chromium-bearing vanadium titanium magnetite with chromium, a new process of “direct reduction-electric furnace smelting separation” has been developed for recovering the iron, vanadium, titanium and chromium in recent years. In this paper, FactSage, one of the most frequently-used thermodynamic calculation software, was used to calculate the reduction degree of Fe, V and Cr with different nC/nO (mole ratio of carbon and oxygen). It was found that the suitable operating conditions of direct reduction process were nC/nO > 1.07 and T > 1473 K. In addition, the direct reduction experiment of Hongge vanadium titanium magnetite was carried out and the obtained samples after direct reduction were analyzed by XRD and chemical composition. The result shows that the metallization rate of carbon-containing pellet is nearly 90%.

To improve CO2 separation performance, porous carbon nanosheets (PCNs) were used as a filler into a Pebax MH 1657 (Pebax) matrix, fabricating mixed matrix membranes (MMMs). The PCNs exhibited a preferential horizontal orientation within the Pebax matrix because of the extremely large 2D plane and nanoscale thickness of the matrix. Therefore, the micropores of the PCNs provided fast CO2 transport pathways, which led to increased CO2 permeability. The reduced pore size of the PCNs was a consequence of the overlapping of PCNs and the polymer chains penetrating into the pores of the PCNs. The reduction in the pore size of the PCNs improved the CO2/gas selectivity. As a result, the CO2 permeability and CO2/CH4 selectivity of the Pebax membrane with 10 wt% PCNs-loading (Pebax-PCNs-10) were 520 barrer and 51, respectively, for CO2/CH4 mixed-gas. The CO2 permeability and CO2/N2 selectivity of the Pebax-PCNs-10 membrane were 614 barrer and 61, respectively, for CO2/N2 mixed-gas.

A new absorbent of nanometer-size TiO2 colloid for Cu(II) was studied in this work. The adsorption rate could reach above 99% when the pH values were at the range of 5–6. The adsorption balance time, adsorption capacities, and the eluent were investigated. A novel method of trace Cu(II) preconcentration and separation with nanometer-size titanium dioxide colloid and determination by flame atomic absorption spectrometry (FAAS) was advanced. The detection limit (3σ) of the method was 1.15 μg · L−1, and the relative standard deviation (R.S.D) was 1.53% (n=6). Environmental sample experiments were also conducted to test the feasibility of the method, and it came out that the recovery rates were between 95.9% and 97.8%.

Using response surface method to determine the optimal technological conditions of biomass-based precursor preparation, magnetic Fe3O4 particles were loaded on the surface and internal channel of biomass-based precursor to prepare a magnetic biomass-based solid acid catalyst using the sol-gel method. To investigate the performance of the magnetic catalyst, it was used to hydrolyze cellulose into reducing sugar, whose structure was characterized by infrared spectrum analysis. The optimum process conditions of biomass-based precursor preparation was obtained by quadratic regression model as a carbonization temperature of 549 °C, carbonization time of 13 h, sulfonating temperature of 121 °C, and sulfonating time of 6 h. Using the biomass-based solid acid catalyst to hydrolyze cellulose, a reducing sugar yield of 57.36% was obtained. Compared with the traditional solid acid catalysts, the total reducing sugar yield was increased by 65%. The infrared spectrum analysis showed that magnetic Fe3O4 particles were combined successfully with biomass-based precursor. This magnetic biomass-based solid acid catalyst has a carbon structure layer of vermicular disorder and possesses high stability.