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Lignocresol was isolated from softwood with p-cresol using sulfuric acid and phase separation. An alkaline treatment of the lignocresol, followed by acidification, selectively yielded a guaiacyl coumaran, G1, in the acid-soluble fraction. With further alkaline treatment of G1 in 0.5 M of NaOH solution at 170 °C for 60 min, it was strongly suggested that a guaiacyl benzofuran derivative, G2, was obtained by the elimination of formaldehyde, based on analytical data of the reaction mixture. The process is very unique and well-designed based on the reactivity of Cα-ethers, or Cα-OH, Cβ-aryl-ethers, and Cγ-OH of lignin, although condensation reactions via formaldehyde occurred in parallel to give condensed products with a diarylmethane structure. Because these phenolic dimers, G1 and G2, were recovered from the guaiacyl unit linked with the neighboring guaiacyl units via two Beta-aryl-ether bonds, they are promising lignin-derived chemicals that are obtainable in a high yield.

Three esters of Hinoki cypress (Chamaecyparis obtusa)-lignophenol(p-cresoI type, HCLC), acetate (HCLCAc), benzoate (HCLCPh) and oxyallylcarbonate (HCLCalloc), were investigated using FT-1R, ¹H NMR, SEC, TGA, TMA and DSC. These esters demonstrated larger MW than lignophenol (LP) due to electrostatic interaction and inter- and intra-molecular interactions of ester side chains. Both TGA and TMA showed higher thermal stability and good plasticity at a lower temperature than HCLC. The thermal stability of esters were evaluated using Ozawa plots of the TGA analysis data. Improvement of these properties depends on both ester linkages and side chains of esters. Moreover, DSC showed clear Tg on the first run without exo-thermal peaks, that means no thermal degradation. These results show that it is possible to control the properties of lignophenol esters and to investigate unknown thermal properties of main chains in HCLC based on native lignin. [ABSTRACT FROM AUTHOR]

Lignophenol, a lignin-based functional polymer, has a higher protein adsorption capacity than other conventional lignins. However, it has been difficult to find a clear correlation between the primary structure (e.g. functional groups, molecular weight) and the adsorption capacity. In this study, lignocresol and bovine serum albumin (BSA) were selected as a standard lignophenol and protein, respectively. We found that aggregation of lignocresol powder in aqueous solution has little influence on BSA adsorption. In contrast, pressing of lignocresol significantly decreased the adsorption capacity probably because lignocresol molecules were packed densely by intermolecular van der Waals force and hydrogen bonding. Precipitation in nonpolar solvents also led to a decreased adsorption capacity, suggesting that molecular rearrangement in various poor solvents has an effect. The protein adsorption capacity of lignophenol can be controlled by changing its higher order structure using these easy methods. [ABSTRACT FROM AUTHOR]

AbstractCrystallized mesoporous carbon was produced from ligno-p-cresol, a lignin derivative obtained by phase separation with p-cresol and sulfuric acid, onto which 3% nickel and 2% calcium were co-loaded, by carbonization at 900°C. Subsequent pulverization followed by soaking in acid improved the crystallinity of carbon with an increased volume of mesopore, attaining approximately 90% and 99% removal of nickel and calcium, respectively. These aspects implied both enhancement of electroconductivity and liquid phase adsorption capacity of the carbon with a good outlook on the recovery and reuse of the two metals. In particular, combination of wet milling using small beads and mild soaking with diluted acid was appropriate in respect of relevant properties of the carbon, including the particle size. It can thus be concluded that incorporation of such post-treatments into the manufacturing process of carbon products is greatly advantageous. [ABSTRACT FROM AUTHOR]