| Over the past few decades, fossil fuels have provided a variety of fuels and chemicals for the community, promoting the rapid development of society. However, with its growing consumption and the worsening environmental pollution, people should search clean and renewable energy in order to replace fossil fuels. Biomass is the most abundant renewable resources, it can be converted to the platform compound of 5- hydroxymethylfurfural（5-HMF） and the derivative of 5-ethoxymethylfurfural（EMF） through a cost-effective way. When 5-HMF as a raw material, fuels and bulk chemicals can be produced further. EMF has also been suggested as a potential biological liquid fuel or fuel additive. They have been considered as the most promising fossil fuel alternative. Base on this, the contents of this paper include the following aspects:（1） We have presented a synthesis route for magnetically-recoverable carbonaceous material（PCM） and magnetically-recoverable carbonaceous material functionalized with sulfonic acid groups（PCM-SO3H） by the hydrothermal synthesis method using glucose, fructose and sucrose as the carbon source and Fe3O4 nanoparticle as the iron source. The materials were characterized by field emission scanning electron microscopy（SEM）, transmission electron microscopy（TEM）, FTIR spectroscopy, X-ray diffraction, VSM, N2 adsorption-desorption, thermal gravity analysis（TGA） and elemental analysis. The results revealed that the several types of catalysts we prepared have the feature of good thermal stability, strong saturation magnetization（maximum of 19.5 emu/g）, strong acid concentrations and separated from the mixture system after the reaction quickly.（2） The dehydration of fructose to 5-HMF was performed over the catalysts of PCM and PCM-SO3 H. The effects of reaction conditions on the reaction were studied. The results showed that a 5-HMF yield of 88.2% with a 98.5% fructose conversion was obtained at 110 oC for 90 min in DMSO with PCM-SO3H-1 as catalyst. Futhermore, we have studied the etherification of 5-HMF to EMF. A EMF yeild of 85.6% with a 98.9% 5-HMF conversion was achieved at 100 oC for 8 h in ethanol with PCM-SO3H-1 as catalyst. Finally, the one-pot reaction of fructose to EMF was studied and the effect of DMSO content in the solvent system for the reaction was mainly investigated. Under the optimal reaction conditions, the conversion of fructose was 98.4%, the yield of EMF was 69.8%.（3） We have presented a synthesis route for a series of new magnetic carbon composites（MCCs） through high temperature calcination method using agricultural straw as the carbon source. The new materials were impregnated with activation treatment by ZnCl2 to increase the catalyst surface area and pore volume, so as to achieve the purpose of increasing the amount of load acid. The new materials were characterized by XRD, FE-SEM, TEM, N2 adsorption-desorption, VSM, FTIR spectroscopy and TGA. The results showed that MCCs has high thermal stability, large specific surface area and pore volume. By measuring the amount of acid, it shows that the catalyst MCCs has strong acid concentration（1.14 mmol/g）.（4） The effects of reaction conditions for the conversion of fructose and the distribution of product using fructose and inulin as raw materials over the magnetic carbon composites MCCs were studied. The results revealed that the highest HMF yield of 83.4% was obtained at 110 oC for 120 min. In addition, the applicable scope of the catalysts was detected by processing fructose to EMF with the yield of 64.2%. The used catalyst could be recyc led repeatedly without vast loss of catalytic activity after four runs. |
