No abstract

In this work, a fatty alcohol polyoxyethylene ether based nonionic surfactant named JFC−M was introduced into a dilute phosphoric acid plus steam explosion of poplar for the enhancement of fermentable sugar production. Factors influenced the pretreatment efficiency such as JFC−M, phosphoric acid, steam explosion pressure, and residence time were optimized by single factor and orthogonal test. An 86.3 % cellulose recovery rate was achieved. Besides, an 85.7 % enzymatic saccharification rate was obtained under the optimized parameters as follows: 1 : 2.5 solid/liquid rate, 2 h pre‐soaking time, 1.0 v/v% JFC−M, 2.0 wt% phosphoric acid, 2.2 MPa steam explosion pressure, 120 s residence time. The morphological and structural characteristics of samples before and after pretreatment were characterized by scanning electron microscopy, X‐ray diffraction, and Fourier transform infrared techniques, showing that the adding of JFC−M was of a notable influence on overcoming the biomass recalcitrance of feedstock and boosting cellulose digestion.

The deconstruction of lignocellulose biomass is a key step in biorefinery that requires directional control and high efficiency. Peracetic acid and FeCl3 were adopted in this study during hot water pretreatment, so that the directional deconstruction of poplar wood was enhanced, boosting the subsequent separation of hemicellulose and enzymatic hydrolysis of the remaining biomass, avoiding the necessity of employing high temperature and pressure. A hemicellulose removal (as in xylan) of 98.23 % was achieved. The pretreatment conditions were: 5.7 w/v% peracetic acid, 0.05 mol L−1 FeCl3, 100 °C for 60 min; the results obtained were: 88.63 % hemicellulose removal (as in xylan), 73.38 % cellulose recovery rate, and 85.92 % cellulose enzymatic saccharification rate. The structure, crystallinity, morphology, and surface chemistry of samples were analyzed by scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. The results showed that efficient pretreatment and cellulose enzymatic saccharification could be achieved under moderate pretreatment conditions, promising good potential in biomass conversion.

Pretreatment is an indispensable process in lignocellulosic bioethanol production. In this work, a surfactant agent JFC was introduced into the dilute phosphoric acid plus steam explosion pretreatment scheme for fermentable sugar production using poplar as substrate. Four crucial factors (phosphoric acid concentration, surfactant concentration, pressure, and residence time) affecting the pretreatment efficiency were optimized using the single factor tests. The optimal parameters obtained were as follows: 1:2.5 solid/liquid rate, 2 h pre-soaking time, 1.5 %(v/v) JFC-M + 2.0 wt% phosphoric acid, 2.0 MPa pressure, and 120 s residence time, resulting in a maximum cellulose recovery rate of 86.33 % and enzymatic saccharification rate of 84.62 %, which was 38.97 % higher than that of control. The morphological and structural characteristics of samples before and after pretreatment, were characterized by the scanning electron microscopy (SEM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) method. The addition of JFC-M was of a notable influence in overcoming biomass recalcitrance and boosting cellulose digestion, showing great application potentials in biomass conversion process.