Factors Influencing Polyol Liquefaction of Nut Shells of Different Camellia Species

Abstract

The liquefaction rates and kinetics of nut shells of different Camellia species in PEG400/glycerol/H2SO4 liquefying solvent were investigated. Changes in major components including cellulose, hemicellulose, and lignin as well as cellulose crystallinity of the nut shells were determined. The compositions of the liquefaction residues were analyzed. Results indicated that, under the same conditions, the liquefaction rates of nut shells of different Camellia species were noticeably different and the PEG400/glycerol/H2SO4 liquefaction agent was not suitable for the liquefaction of the nut shells of all Camellia species. The burst liquefaction of Camellia nut shells (CNSs) that occurred during the first stage was due to the rapid degradation of hemicellulose, acid-soluble lignin, and amorphous cellulose. The liquefaction during the second stage became very slow, mostly because the swelling and decomposition of crystalline cellulose was very difficult to achieve with the liquefying agent and the liquefaction products inhibited liquefaction at later stages. The liquefaction residues of CNSs were composed of crystalline cellulose, small amounts of hemicellulose, acid-insoluble lignin, and ash. Ash was partially dissolved in the liquefying agent. The liquefaction rates of all CNSs tested in this study showed linear relationships with time, with coefficients of determination (R 2 ) greater than 0.7082, indicating that the liquefaction of CNS was a pseudo-firstorder reaction.

Chemical Composition and Optimization of Liquefaction Parameters of Cytisus scoparius (Broom)

“…On the other hand, phenol is more toxic than the polyalcohols used and less green since most of the polyalcohols can be obtained from crude glycerol or other non-petroleum materials. Several lignocellulosic materials have been liquefied with polyalcohols such as agricultural wastes, for example, wheat straw [20], cornstarch [21] or rice straw, oilseed rape straw and corn stover [22], forest management residues, such as several woods [15,23,24], barks [16,25,26] or shells [14,27,28] and also some industrial residues such as orange peel [29]. The lignocellulosic material is composed of carbohydrate polymers (cellulose and hemicelluloses), lignin and a small part of other compounds (extractives, salts and minerals).…”