Pretreatment of Wheat Straw with Phosphoric Acid and Hydrogen Peroxide to Simultaneously Facilitate Cellulose Digestibility and Modify Lignin as Adsorbents

Abstract

Effective valorization of lignin is crucial to achieve a sustainable, economic and competitive biorefinery of lignocellulosic biomass. In this work, an integrated process was proposed based on a concentrated phosphoric acid plus hydrogen peroxide (PHP) pretreatment to simultaneously facilitate cellulose digestibility and modify lignin as adsorbent. As a dominant constitutor of PHP pretreatment, H2O2 input and its influence on the overall fractionation/lignin modification performance was thoroughly investigated. Results indicated that wheat straw was fractionated more efficiently by increasing the H2O2 input. H2O2 input had a significant influence on the digestibility of the obtained cellulose-rich fraction whereby almost 100.0% cellulose-glucose conversion can be achieved even with only 0.88% H2O2 input. Besides, the adsorption capacity of lignin on MB was improved (74.3 to 210.1 mg g−1) due to the oxidative-modification in PHP pretreatment with H2O2 inputs. Regression analysis indicated that –COOH groups mainly governed the lignin adsorption (R2 = 0.946), which displayed the considerable adsorption capacities for typical cationic substances. This work shows a promising way to integrate the lignin modification concept into the emerging PHP pretreatment process with the dual goal of both cellulose utilization and lignin valorization.

Efficient bioenergy recovery from different date palm industrial wastes

“…However, the breakdown of other components is the reason for the increase in glucan percentage. Concentrated phosphoric acid pretreatment had a comparable impact on the amount of glucan in wheat straw previously [43]. Hemicellulose is more susceptible to acid pretreatment than other biomass components [20].…”

Artificial neural network modeling to predict the efficiency of phosphoric acid-hydrogen peroxide pretreatment of wheat straw

“…Through the simultaneous saccharification and fermentation (SSF) process at 15.3% solid loading for 120 h, it could harvest 15.5 g ethanol from 100 g wheat straw (Qiu et al 2018). The PHP pretreatment can also separate the hemicellulose and lignin from biomass to prepare high-value products, such as oligosaccharides and supercapacitors (Wan et al 2019;Liu et al 2021). The oxidative tail gas from PHP pretreatment could be employed to achieve 68% to 98.3% methyl blue degradation (Lei et al 2022).…”

Prediction of phosphoric acid plus hydrogen peroxide (PHP) pretreatment efficiency using artificial neural network modeling

“…Furthermore, with the simultaneous sacchari cation and fermentation (SSF) process at 15.3% solid loading for 120 h, it could harvest 15.5 g of ethanol from 100 g of wheat straw (Qiu et al, 2018). PHP pretreatment might also separate the hemicellulose and lignin from biomass to manufacture high-value products, such as oligosaccharides or supercapacitors (Liu et al, 2021;Wan et al, 2019). Besides, the oxidative tail-gas from PHP pretreatment may be applied to produce 68.0-98.3% methyl blue degradation (Lei et al, 2022).…”