碱预处理糠醛渣性质及其纤维素酶解研究

以糠醛渣为原料进行碱法预处理,对比了处理前后的样品成分、结晶度、表面特性、红外谱图的变化以及对纤维素酶解的影响。研究结果表明:经NaOH处理样品,木质素脱除量随着温度升高而增加,120 ℃ 处理后的样品木质素脱除了 10.22 %,而碱性过氧化氢处理样品木质素脱除率达到 12.6 %。NaOH预处理后的样品酶解糖化率随处理温度的升高而降低。每克纤维素加入纤维素酶 12 FPU、纤维二糖酶 15 IU,120 ℃ 经NaOH预处理样品,酶解 72 h 后糖化率为38.6%,比原料糠醛渣低21.0个百分点,而经 60 ℃,6 h 碱性过氧化氢处理后的样品,酶解 72 h 糖化率可达到 86.6 %,比原料糠醛渣高27.0个百分点。NaOH预处理后样品红外谱图检测,证明生成了新的醚键。碱法预处理后的样品结晶度要比未处理的样品的稍高,且表面更加光滑。

Furfural Residues Properties and Enzymatic Hydrolysis after Alkali Pretreatment

After the furfural their residues were pretreated with sodium hydroxide,its composition,crystallinity,surface properties,infrared spectrum and their effects on enzymatic hydrolysis were compared with those without pretreatment.The results showed that the lignin removal proportion increased with the increase of temperature by NaOH pretreated.At 120 ℃,the lignin removal rate was 10.22 %,but it reached 12.6 % for alkaline hydrogen peroxide pretreated sample.The enzymatic hydrolysis rate of samples decreased when the pretreated temperature increased. After enzymolysis for 72 h by loading 12 FPU cellulase and 15 IU cellobiase per gram cellulose,the yield of saccharification was 38.6% by pretreatment of NaOH at 120 ℃,which is 21.0 percent point lower than that of raw material.However,by using alkaline hydrogen peroxide as pretreat agent under the conditions of 60 ℃,6 h,the yield of saccharification was up to 86.6 % after enzymolysis for 72 h,which was 27.0 percent point higher than that of raw material.The FT-IR spectrum of the sample pretreated by NaOH suggested that new ether boned was generated.The crystallinity of pretreated sample was slightly higher and its surface was smoother than that of untreated sample.