Plant extracts and oxidative degradation of lignin
Abstract: Lignin is nature reserves second only to cellulose, a renewable resource, its second only to cellulose in a number of nature, the estimated annual worldwide growth of the plant can produce 150 billion tons of lignin, crop stalks each year there are only 500 ~ 600 million tons. Past development of lignin did not realize it value, but with the use of oil resources shortage lignin preparation of high value-added products has become a hot spot.
Currently more than 95% of the lignin remains as an industrial waste pulp, with the waste water directly into rivers or burned after concentration, pulp wastewater discharge not only a waste of resources, but also pollute the environment, its good resource utilization has practical significance for the socio-economic development and environmental protection.
In this experiment, KOH as extracting agent to crushed peanut shells as raw material to extract lignin obtained by extracting agent and the optimal reaction conditions by orthogonal experiment, the resulting optimal conditions: water bath temperature of 40 degrees, holding time 2.5 h. Amount 20mL / g, alkali concentration of 0.5 mol / L.
The resulting oxidation of lignin degradation test. By sodium hydroxide, hydrogen peroxide reactant, copper sulfate pentahydrate as a catalyst for the reaction with lignin, and the use of different mixing extractants be extracted under a series of conditions. The resulting product was concentrated after performing its analysis by IR, UV spectra and temperament. Some derivatives can be converted into vanillin draw conclusions, so further research can make further use of lignin to achieve its value.
On the other hand, it can be seen that a variety of aromatic compounds generated after degradation of lignin, lignin which may be provided instead of petrochemical raw materials in future. Thus a very large study of lignin extremely practical significance derivatives subsidiary, which is the same direction of our efforts.
KeyWords:Lignin;abstract;Oxidative degradation;Application
目 录
1 引言 1
1.1 研究背景 1
1.2 木质素结构及理化性质 2