Extraction of Hemicellulose from Loblolly Pine Woodchips and Subsequent Kraft Pulping

Abstract

A mild borate assisted alkaline pretreatment was applied to Loblolly pine chips prior to kraft pulping to extract hemicelluloses. The extraction was performed at 90 °C for 4 h with 6% (w/w based on o.d. sample) alkali and 5% (w/w based on o.d. sample) boric acid. This process could recover 37.7% hemicellulose from the woodchips with only a 6.9% decrease in the cellulose degree of polymerization (DP). During the subsequent kraft pulping of the extracted woodchips, the process requires careful optimization to obtain the same yield (∼52%) and maintain high pulp quality as the control cook. For the kraft cooking of extracted chips, similar pulp yield and physical strength could be reached by either decreasing the cooking time (reduced Hfactor by 30%) or decreasing the chemical charge by 25% in comparison with the control cook.

Loblolly pine pretreatment by ionic liquid-glycerol mixtures

“…These results suggest the possibility that the biomacromolecular "glue," between wood cells, which is primarily lignin, has been removed by pretreatment [43]. Figure 4 and Table 1 show a correlation between mass removal during pretreatment and sugar yield (glucose in Fig.…”

“…These regions are comprised mainly of lignin and pectin, with lesser amounts of hemicelluloses [43]. The morphological changes in loblolly pine with pretreatment can be seen in the SEM images presented in Fig.…”

Mechanochemical Transformations of Biomass into Functional Materials

“…[181][182][183] Two factors are vital in understanding the value of lignin in the biorefinery: the ease of lignin extraction, which is facilitated by treatments that reduce cross-linking to other cell wall polymers, and a structure that facilitates downstream processing. [184] Significant work has been focused on the [197] isolation of lignin from lignocellulosic biomass and depolymerization of lignin towards the production of biofuels and chemicals. [17,[185][186][187][188][189] Due to the extensive functionalities listed above, lignin-based carbon materials have been developed for energy storage, catalysis, and pollutant removal.…”

Effect of Boric Acid Addition on the Prehydrolysis of Whangee

“…Furthermore, ideal bamboo-dissolving pulp with high brightness (92.4% ISO) and α-cellulose content (94.9%) has been obtained (Batalha et al 2012). Presently, a number of methods have been proposed for extracting hemicellulose in the prehydrolysis stage, including auto-hydrolysis (Leppänen et al 2011), dilute acid (Jeong et al 2010), mild alkali extraction (Huang and Ragauskas 2013), organic acid (Li et al 2010;Scordia et al 2011), and solid acid pretreatment (Dhepe and Sahu 2010). Among those methods, dilute acid extraction usually resulted in a lower pulp yield and physical properties, which were attributed to the acidity in the pretreatment medium (Aldajani et al 2009).…”

“…Among those methods, dilute acid extraction usually resulted in a lower pulp yield and physical properties, which were attributed to the acidity in the pretreatment medium (Aldajani et al 2009). According to Huang and Ragauskas (2013), the addition of boric acid (BA) in alkali solution can extract more hemicellulose from softwood and have little influence on cellulose.…”