Synergy of Hydrothermal and Organic Acid Washing Treatments in Chinese Fir Wood Vinegar Preparation

Abstract

Pretreatment is an effective method to change the pyrolysis behavior and improve the product properties of biomass. In this study, the effects of hydrothermal treatment (HTT) and hydrothermal treatment combined with organic acid washing (HTT-A) on Chinese fir waste (CF) pyrolysis and preparation of wood vinegar (WV) were investigated. The results indicated that HTT promoted the decomposition of hemicellulose and disrupted the chemical structure, while HTT-A partly removed the lignin as well as hemicellulose. HTT-A showed a more effective removal efficiency of alkali/alkaline earth metals (AAEMs) than HTT. Both HTT and HTT-A delayed the initial decomposition temperature but promoted the pyrolysis process. The yields of WVs increased after HTT and HTT-A, while the moisture contents reduced, obviously. HTT increased the relative contents of phenols from 47.04 to 59.85% but reduced the relative contents of acids from 24.31 to 18.38%, whereas HHT-A reduced the relative contents of phenols but increased those of aldehydes. In addition, HTT and HTT-A showed the different effects on chemical compositions of WVs, especially for phenolic and acid compounds. This study indicated that HTT and HTT-A were the efficient methods to produce WVs with target chemical components, which would be conducive to the efficient application of WVs.

Hydrothermal Carbonization of Searsia lancea Trees Grown on Mine Drainage: Processing Variables and Product Composition

“…At 275 °C, the calorific vale of the woody biomass was upgraded from 20.32 to 29.67 MJ/kg, while the carbon content increased from 49.02 to 70.99% . A recent study conducted by Lu et al on furniture residues at a much lower temperature of 180 °C led to an increase in the biomass total carbon from 47.6 to 52.10%.…”

“…At 275 °C, the calorific vale of the woody biomass was upgraded from 20.32 to 29.67 MJ/kg, while the carbon content increased from 49.02 to 70.99%. 19 A recent study conducted by Lu et al 20 furniture residues at a much lower temperature of 180 °C led to an increase in the biomass total carbon from 47.6 to 52.10%. We investigated the use of biomass from the southern African indigenous semi-hardwood tree Searsia lancea (L.f.) F.A.Barkley (Anacardiaceae, mango family) to produce pelletized solid fuels.…”

Bringing Material Concepts into Conventional Biorefineries: Considerations of Sources, Preparations, and Applications of Lignin Nanomaterials

“…It generates alkali lignin (AL) under various temperatures with pH values generally higher than 10. Furthermore, there are numerous hydroxyl groups on the surface of AL, and etherified phenolic acid groups exist, which play an essential role in cross-linking. − In the current pulping industry, alkaline pretreatment is mainly used for the delignification of nonwood feedstocks, such as bagasse, wheat straw, and hemp …”