Ning Ai

TG-FTIR Analysis of Three Crop Straws Pyrolysis

The influence of heating rate on pyrolysis characteristic and the products evolution performance of sorghum straw, maize straw and cotton straw had been investigated by thermogravimetric analyzer coupled with Fourier transform infrared spectrometry (TG-FTIR), and distributed activation energy model (DAEM) was employed to calculate the kinetic parameters. The results show that with the increasing heating rate, the initial pyrolysis temperature and the maximum weight loss temperature shift to high temperature zone, the maximum weight loss rate increases, and the pyrolysis peak of hemicellulose starts to appear. The pyrolysis characteristic parameters of three crop straws were different because of their physical, chemical characteristics and structure characteristics. The activation energy E of sorghum straw, maize straw and cotton straw is 150~223kJ/mol, 141~217kJ/mol and 155~242kJ/mol, while the corresponding pre-exponent factor distributes between 1013and 1019 s-1, between 1013 and 1017 s-1, and between 1014 and 1020 s-1,respectively. The main pyrolysis products of three crop straws are H2O, CO2, CO, CH4, formic acid and phenol. The research provides certain theoretical reference for energy regeneration utilization of straw biomass.

Density Functional Theory Study on the Absorption of CO2 by the Ionic Liquid of 1-butyl-3-methylimidazolium Acetate

The absorptions of CO2 on the 1-butyl-3-methylimidazolium acetate ([Bmi [Ac]) with different substituents are calculated systematically at GGA/PW91 level. Three hydrogen bonds are formed between [A and cations of 1-n-[Bmi [A ([NBmi+) and 1-tert-[Bmi [A ([TBmi+). The interaction between CO2 and the [NBmi [A by a C-O bond is much weaker than that with the [TBmi [A by forming a O...O...C...C four member-ring. The chemisorption of CO2 on the ion pairs of [NBmi [A is much weaker than that on the [TBmi [A, resulted from the absorption energies analysis. The frontier molecular orbitals shows the electronic density overlap between absorbed CO2 and the [A in CO2-[NBmi [A is much weaker than that in [TBmi [A. Therefore, the chemisorption of CO2 on the ion pair of [NBmi [A is much weaker than that on the [TBmi [A. The ionic liquids based [NBmi+ can be used repetitively, and the adsorbed CO2 would be easier desorbed.

Solubilities of CO2 in 1-Allyloxy-3-(4-Nonylphenoxy)-2-Propanol Polyoxyethylene Ethers

1-allyloxy-3-(4-nonylphenoxy)-2-propanol polyoxyethylene ethers (ANAPEs), a new type of absorbent, are polymeric surfactants with different adduct numbers. In this work, ANAPEs, including SN-10 with adduct number of 10 and SN-15 with adduct number of 15, were prepared for CO2 absorption using the isochoric saturation method. Densities of the ANAPEs at atmospheric pressure were measured by a 5.567 ± 0.004 cm3 pycnometer, which decreased with increased temperature. Solubility data of CO2 in ANAPEs were measured within the pressure range of 0 – 600.0 kPa and temperature range of 303.15 – 323.15 K at 10 K intervals and could be calculated on the basis of experimental data of p, xCO2 and bCO2. The solubility of CO2 in absorbents increased linearly with increasing pressure and decreased with increasing temperature at all the pressures. The solubility of CO2 in SN-15 is the highest at all temperatures, but almost the same with SN-10 at 303.15 K over pressures (p < 350kPa), which indicates physical dissolution process. Henry’s constants were determined from solubility data. With increasing temperature, Henry’s constants increased. Thermodynamics of CO2 absorption were calculated including enthalpy, entropy, and Gibbs energy. The absolute value of ΔsolH based on Hx of SN-15 is largest at 303.15 K and indicates stronger SN-15/CO2 interactions, consistent with solubility of CO2 based on Hx. The negative enthalpy demonstrated exothermic process, which means the dissolution of CO2 in ANAPEs is favourable enthalpically. The ΔsolG shows positive value.

Comparison of Cellulose Pyrolysis in Molten NaOH, Ca (OH)2 and Composite Alkali

With the rapid increase of social requirements on energy, as well as the increasing deterioration of the global environment, energy production becomes one of the most important future challenges for human society. In this context, biomass has become a renewable resource with high potential for energy production [1]. In recent years, the demand for and use of renewable energy has increased globally [. Bio-energy is regarded as one of the key options to mitigate greenhouse gas emissions and substitute fossil fuels, especially obvious in Europe. Over the past 10-15 years, heat and electricity production from biomass increased with some 2% and 9% per year, respectively, biofuel production increased about eight-fold in the same period between 1990 and 2000. Biomass contributed some two-thirds of the total renewable energy production in the European Union (EU) (2000 PJ) or 4% of the total energy supply in 1999 [.

Conversion of Rice Straw to Bio-Fuel by Pyrolysis in Molten KCl-LiCl

The objective of this study was to provide background date on rice straw pyrolysis in molten KCl(40mol%)-LiCl(60mol%). The effects of pyrolysis temperatures and sweep gas flow rates on the pyrolysis products yields and their chemical compositions were studied. The temperatures of pyrolysis and sweep gas flow rates were varied in the range of 380°C -540°C and 60L/h-260L/h, respectively. The compositions of gaseous products were analyzed by gas chromatography, and that of bio-oil obtained was investigated using gas chromatography-mass spectroscopic(GC-MS) technique. The yield of gaseous products increases with the increasing temperature, the char yield has demonstrated a downtrend, and the maximum yield of bio-oil is up to 15.43 wt.% at 460°C. The yield of char decreases with the sweep flow rate, the gaseous has a minimum yield at 100L/h, and the maximum yield of bio-oil is 15.43wt.% at 100L/h .The main gaseous products are CO, CO2 , H2 and CH4. Ketones and phenols are the main compounds in the bio-oil, the presence of molten inhabites their formation, and promotes the production of furfural. The bio-oil attained from pyrolysis is a potential source of renewable fuel and chemical feedstock.

Conversion of sawdust to bio-fuels by pyrolysis within molten sodium hydroxide

Sawdust, a renewable by-product of furniture manufacturing industry, is an energy source that can be utilized to meet the increasing demands for energy. Pyrolysis of sawdust was performed in a self-designed reactor under the conditions of nitrogen atmosphere, the effect of feeding rate, flow rate of sweeping gas, sawdust type, and inorganic salts additive on the pyrolysis product yields from sawdust have been investigated. The results shows that the char yield increased gradually with the increasing of feeding rate, the maximum yield of liquid and gaseous attained at the feeding rate of 1.36g/min; the liquid yield decreased gradually with the increasing of sweeping gas flow rate, and the maximum of gaseous attained at the flow rate of 100L/h; different kinds of sawdust can be used to produce different pyrolysis products, and ZnCl2 can retrain the formation of liquid and char obviously, the effect on formation of gaseous was slight.

Influence of molten salts on pyrolysis characteristics of rice straw

In order to investigate the effects of molten salts on pyrolysis characteristics of rice straw, the pyrolysis behaviors of rice straw had been investigated with thermogravimtirc analysis by changing cations (Na+, K+) and anions (Cl-, CO32- and SO42-) of the molten salts, respectively. The results indicated that the pyrolysis of rice straw was occurred in the range of 200°C and 400°C. With the increase of heating rate, hysteresis was existed during the pyrolysis process, and the maximum weight loss rate increased. The pyrolysis happened at a lower temperature range and the volatile matter vapored easily under the role of CO32-, and SO42- had advantages of fixing charcoal under the same cation conditions. Compared with Na+, it was easier for K+ to generate charcoal under the same anion conditions. Integration method Ozawa was used in kinetic analysis on the samples processed by deducting the added salts, the results showed that the activation energy of rice straw under the role of NaCl, Na2SO4 and KCl decreased compared with that of the sample without additives, while the activation energy processed by Na2CO3 increased. This research can provide a certain reference for the exploitation and utilization of agricultural residues.

Keeping Pace with Economic Development and Improving Professional Education Level - Endeavors of Marine Science Education to Actively Adjust to National Strategy and Local Economy

Taking “Introduction to Oceanography” as an example, which is the basic course and opened in the colleges covering the major of marine science, this paper discusses how to take the initiative to adapt to the national strategic plan and local economic development in the process of basic education of marine science. According to Chinas current situation of the marine industry structure, this paper presents that the interface between marine science education and the secondary industry should be strengthened, meanwhile the integration among the basic courses and the actual production and the scientific research should be focused on. Colleges covering the major of marine science should take the initiative to explore training modes to enhance the qualities of talents of different level, and to carry out featured training based on their own characteristics of personnel positioning.