Production of Liquefied Oil Palm Empty Fruit Bunch Based Polyols via Microwave Heating

Abstract

Optimization of microwave-assisted liquefaction of oil palm empty fruit bunch fiber (EFB) and cellulose (EFBC) in ethylene glycol (EG) was carried out to produce polyols. The liquefaction residues and hydroxyl numbers of the resultant polyols from respective sources were studied and compared. EFB produced a minimum residue of 3.22% at the optimal parameters of 160 °C and 15 min. Meanwhile, optimum liquefaction of EFBC produced 1.03% residue at 175 °C and 40 min. The maximum hydroxyl numbers of both EFB (749.22 mg KOH/g) and EFBC (639.91 mg KOH/g) polyols were obtained at optimum conditions. FTIR analysis revealed the degradation mechanism of cellulose and lignin in EFB at different temperatures. Lignin was found to be liquefied easily at lower temperatures (130 and 145 °C). However, most of the cellulose began to be liquefied at the optimum temperature (160 °C) and severely degraded at higher temperatures (175 and 190 °C).

The Degradation and Repolymerization Analysis on Solvolysis Liquefaction of Corn Stalk

“…The liquefaction yield tended to be stable after the reaction time was >90 min. In the case of temperature ≥150 °C, the partial degradation of the crystalline cellulose occurred, as reported in previous literature [ 32 ]. Moreover, the liquefaction yield at each investigated temperature reached the maximum value at the reaction time of 120 min.…”

Effect of Catalysts on the Yield and Properties of Lignin From Microwaveassisted Acetosolv Extraction of Oil Palm Empty Fruit Bunch Fibres

“…As for AlCl 3 , the yield increased from 28.81%-71.57%, with an increment of purity from 83.39%-92.89%. Basically, temperature plays a vital role in lignin extraction as it enhances the degradation of cell walls while the lignin and hemicellulose were decomposed and dissolved in the organic solvent (Amran et al, 2017;2019). The higher yield obtained was also due to the extensive lignin depolymerisation which led to higher lignin solubilisation in the organic solvent, especially with the presence of microwave irradiation (Monteil-Rivera et al, 2012).…”

“…In recent years, concerns over the continuous depletion of fossil resources as well as an increment in ecological awareness have drawn a remarkable interest to reduce the dependence on fossil resources as raw materials. Countless research have been conducted to overcome these issues and lignocellulosic biomass has been considered as the best candidate to replace or provide alternative to petroleum-based materials (Amran et al, 2017). This reason is not only for its sustainability but the content of cellulose, lignin, and hemicellulose in the biomass provide various functionalities and structures that can be tailored into desired applications.…”

Agricultural and Forest Residues towards Renewable Chemicals and Materials Using Microwave Liquefaction

“…Biomass Type. Since Krzan et al first applied microwave energy to liquefaction [19,20], a variety of biomass types including sweetgum sawdust [8]; agricultural residues including bagasse, corn stover, rice straw, wheat straw, cotton stalk, and corncobs [24][25][26]; organosolv lignin of olive tree prunings [27]; Sargassum polycystum C. Agardh [28]; microalgae [29]; Ulva prolifera [30]; wheat straw alkali lignin International Journal of Polymer Science [31]; sugar beet pulp [32]; peony oil palm empty fruit bunch fiber [16]; oil palm empty fruit bunch cellulose [33]; poplar; Chinese fir; bamboo; hemp xyloid stem [22]; mixed softwood pellets [34]; banana pseudostem [35]; coconut fiber [36]; and grapefruit [37] have been studied as raw materials for microwave-assisted liquefaction for the production of renewable chemical platforms and/or biobased materials. The chemical composition (cellulose, hemicellulose, lignin, and ash) and microstructure of the lignocellulose feedstocks greatly differed with each other, which may influence their liquefaction behaviors under microwave heating.…”

“…The significant microwave liquefaction factor is temperature, and the reason may be that temperature enhances and attacks solvents and catalysts onto glycosidic linkages resulting in the decomposition of cellulose into small molecules [69]. The optimum liquefaction temperature and time for oil empty fruit bunch fiber and oil palm empty fruit bunch fiber cellulose was 160°C with 15 min and 175°C with 40 min [33]. The research results on the liquefaction of coconut fiber indicated that the optimal reaction temperature was 160°C [36].…”