Study On The Selection Of Gramineae Energy Grasses And The Saccharification Of Missanthus

With the intensification of the energy crisis and environmental pollution, todevelop and utilize clean and sustainable energy has become an important scientificissue. The research of some tall Gramineous grasses as energy plant and theireffective utilization has been dvoted much attention in many countries.An initial selecting of wild gramineous plant resources in Liaoning Province asenergy plant was carried out in this study. Six kinds of Gramineous grasses with goodcharacters were selected and introduced to Plant Garden of Shenyang NormalUniversity to compare their performance under the same condition. The growthindexes, photosynthetic characteristics and relative indexes, calorific value of the sixkinds of grasses were measured.The study found that the Missanthus sinensis could develope more tillers. Itsaverage daily growth rate of plant height, leaf length was the fastest among thegrasses. It had large biomass just as in wild environment. The net photosynthetic rateand the fluorescence efficiency for the six kinds of grasses had shown that theMissanthus sinensis had a high net photosynthetic rate and fluorescence efficiency.The apparent quantum efficiency, water using efficiency and light saturation point ofMissanthus sinensis were higher than other grasses. All the results showed thatMissanthus sinensis could efficiently use solar energy and this was the physiologicalmechanism of its growth charaters.Calorific values of the six kinds of grasses were determined. The results showedthat Missanthus sinensis had the highest caloric values and had significant differencecompared with other grasses. The suitable mixed combustion propotion with coal was5%.The performance of Missanthus sinensis showed it was a hopful energy grass andit should be studied further. Missanthus were treated by dense acid catalyst and diluteacid hydrolysis. The effect of two-stage acid hydrolysis technology was alsoevaluated. The optimized sulphuric acid hydrolysis conditions were established bysingle factor orthogonal experiment.Dense acid hydrolysis conditions were optimized as follows: acid centration isin 60% and temperature at 60℃for 30 minutes, the ratio of acid-solid is 15:1; the yield of total sugars was reaehed 32%. Dilute acid hydrolysis conditions wereptimized as follows: acid centration was in 6 % and temperature at 160℃for 120minutes，the ratio of acid-solid was 160:1; the yield of total sugars was reaehed over25%.Synthesize two-stage acid hydrolysis optimal conditions, the cellulose materialswas first hydrolyzed by the dense acid hydrolysis optimal conditions, and then theacid concentration was diluted to 6% , the cellulose materials was optimized underdilute acid hydrolysis optimal conditions, the yield of total sugars reaehed over37 %.This was 1.16 times of dense sulfuric acid hydrolysis and 1.46 times of dilutesulfuric acid hydrolysis.