Optimisation of Acetic Acid Lignofibre Organosolv Process

Abstract

Birch wood chips were cooked in acetic acid in the presence of phosphinic acid according to the Lignofibre (LGF) organosolv process. The cooking trials were performed according to an experimental design with process time, temperature, and the presence (or absence) of alkaline preextraction as the factors. Delignification was enhanced by increased temperature and alkaline pre-extraction. Alkaline extraction also limited xylose hydrolysis, as well as the further degradation of xylose into furfural. Degradation and condensation reactions began to take place between dissolved carbohydrates and lignin at higher temperatures and longer cooking times. Formation of pseudolignin, most likely because of reactions between lignin and furfural, was also observed under the harshest cooking conditions. To avoid these unwanted side-reactions, minimise viscosity losses, and preserve the yield, the LGF process time should be limited to 3 to 4 h at 150 °C.

Lignin for Bioeconomy: The Present and Future Role of Technical Lignin

“…LGF pulping showed improved delignification as compared to the mineral acid-catalyzed acetic acid process [114]. The phosphinic acid in the acetic acid LGF process supports acidolysis via phosphinic acid esterification.…”

Modeling of acetosolv pulp yields from plantain stalk

“…The pulp yields were similar to 52.6 % obtained from Miscanthus sinensis bark by the acetosolv process (Ligero et al 2005), 46.3 % for depithed cardoon (Cynara cardunculus) stalks (Ligero et al 2007), 46.56 % for empty fruit bunches from palm oil industry (Ferrer et al 2013) and an average of about 50% for four species of pine (Witayakran et al 2014). However, the use of phosphinic acid and alkaline pre-extraction of the fiber resulted in a higher range of yields from 43.3 % to 79.4% reported for birch wood chips (Kangas et al, 2015).…”

Alternatives for Chemical and Biochemical Lignin Valorization: Hot Topics from a Bibliometric Analysis of the Research Published During the 2000–2016 Period

“…Low molecular weight alcohols have been preferred: ethanol appears as the most frequent solvent [102][103][104][105][106], but examples that use methanol [107][108][109], propanol [110][111][112], and butanol [113][114][115] can be found as well. Low molecular weight organic acids, mainly formic and acetic acids, are other relevant solvents for organosolv treatments [116][117][118][119][120][121] and include the optional addition of hydrogen peroxide to produce in situ performic and peracetic acids [122][123][124]. Many other solvents have been tested [125,126], but a new trend that must be mentioned is the application of solvents obtained from biomass.…”