The Research on Transformed Craft of Bioligical Ethanolof Low Value Seaweed Enteromorpha Prolifera
|School||Ocean University of China|
|Course||Aquatic Products Processing and Storage Engineering|
|Keywords||The energy crisis the sea biomass Enteromorpha pretreatment craft fermentation|
The problem about energy and environment has become the international hot spot and arouses widespread interest. The development of renewable and clean energy has been extremely urgent, following the Chinese energy warning. The article research on the represents of the terrestrial and sea biomass Enteromorpha and bagasse as raw material which are the third generation material of producting ethanol. The Enteromorpha have massive polysaccharides which have high value on nutrition and medicinal purposes, because of the macromolecular weight, the polysaccharides can not be used by yeast,so the polysaccharides must be extracted first using hot water. Peroxide has been used to optimize pretreatment craft through single factor experiments and response surface （SRM） analytical method. The determination of Enteromorpha and bagasse component which are mainly the cellulose, the hemicellulose and the lignin after peroxide pretreatment, meantime, using scanning electron microscope （SEM） abserve the microscopic structure of two kinds biomass pretreated to confirms the effect of the pretreatment. Finally, using ultrafiltration eliminate polysaccharides from enzymolysis fluid of Enteromorpha. The small molecular weight reducing sugar are fermentated to produce ethanol. Fermentation condition has been optimized from the stains, the initial sugar density, the vaccination quantity and the fermentation temperature.The medium has been optimazed from the dosage of magnesium sulfate and the ammonium sulfate.The experiment indicated that the optimized conditions through single factor experiments about lixiviating polysaccharide are: the pretreatment time is 5 h, the liquid-solid ratio is 1:80, temperature is 90℃, and the polysaccharide yield achieves 17.3%. The optimized conditions of Enteromorpha pretreatment craft through the single factor experiment and the response surface analytic methods（RSM） are: the pretreatment time is 12 h, the temperature is 50℃, the peroxide density is 0.2%, the pH is primitive. And the optimized pretreatment craft of bagasse are:the pretreatment time is 36 h, the pretreatment temperature is 110℃, the peroxide density is 0.4%, the pH values are primitive. Under the optimized technological conditions, biomass has been enzymolysised effectly. Through determinating the component of Enteromorpha and bagasse, results demonstrated that the content of hemicellulose plus cellulose of the Enteromorpha and the bagasse achieved 33.7%, 35.1%, espectively. Through determinating the component of the cellulose, the hemicellulose and the lignin of two kinds of pretreated biomass, results demonstrated that H2O2 can remove lignin effectively, so the enzymolysis efficiency enhanced. Observing the microscopic structure of Enteromorpha and bagasse pretreated through the scanning electron microscope（SEM）, results demonstrated that H2O2 has destroied microscopic structure of Enteromorpha and bagasse and the biomass pretreated presented more enzymolysis position spot.The enteromorpha enzymolysis fluid is higher than the bagasse from the reduced sugar , the glucose, ethanol yield ratio.The optimized fermentation conditions of Enteromorpha are: The fermentation stains is the bread yeast, the fermentation time is 1 d, the fermentation temperature is 36℃, the initial original reducing sugar density is 2%, the vaccination quantity is 10%. The optimized fermentation medium conditions are: the magnesium sulfate dosage is 0.4 g/L, the ammonium sulfate dosage is 6 g/L. The ethanol yield of optimized fermentation of enteromorpha achieved 13.2 g （ethanol） /100 g （Enteromorpha）. Taking enteromorpha as raw material fermentation to product ethanol show good application prospect.