Chemical and thermal properties of lignins from oil palm biomass as a substitute for phenol in a phenol formaldehyde resin production

Abstract

Lignins were extracted from oil palm empty fruit bunch after kraft and soda pulping process. The aim of this study was to characterise the chemical and thermal properties of these lignins as well as determine their suitability for partial incorporation into phenol formaldehyde resin. The analytical methods used were CHN analyser, FTIR spectroscopy, UV spectroscopy, TGA, DSC, GPC, 1H NMR and FESEM. The elemental analysis results showed that both lignins had similar contents of C, H and O. FTIR spectra also revealed that both lignins have similar functional groups. Nevertheless, both lignins showed different compositions in terms of molecular weight distribution (M n, M w and polydispersity), reactive site through Mannich reactivity analysis, surface morphology and T g value. The phenolic hydroxyl group content in kraft and soda lignins is 4.1076 mmol/g and 2.5830 mmol/g, respectively. The TGA thermogram showed both lignins had high thermal stability. Based on these analyses, kraft lignin from oil palm empty fruit bunch showed tremendous potential as a partial substitute for phenol in phenol formaldehyde resin production.

Biorefinery Process Combining Specel® Process and Selective Lignin Precipitation using Mineral Acids

“…This second stage began between 200 and 210 °C for the other samples. Different thermal decomposition stages observed for lignin with TGAs are in accordance with other literature reports (Domínguez et al 2008;González et al 2009;Ibrahim et al 2011;Hussin et al 2014).…”

“…1. These results (above 40%) revealed that the obtained soda lignins are stable at high temperature, which is attributed to the formation of highly condensed aromatic structures above 450 °C (Tejado et al 2007;Ibrahim et al 2011).…”

“…A possible explanation for this observation is the higher levels of monosaccharide degradation products contained in this sample. DTGmax is expressed as a single temperature value and can be used to characterize the material's thermal stability (Ibrahim et al 2011). The value of this property could be important to determine which applications this lignin can be used, particularly if it is exposed briefly to moderately high temperatures.…”

Development of Method to Determine the Concentration of Alkali-Soluble Lignin using Coomassie Brilliant Blue G-250

“…As the global effort increases to find a high-valued biorefinery route, the importance of lignin quantity determination has proven to be paramount (Lupoi et al 2015). In pulping and paper-making, and the first generation cellulosic projects, most of the lignin is combusted (Mohamad Ibrahim et al 2011;Ragauskas et al 2014). The heterogenic complexity of the lignin provides a barrier to its fractionation and economical use for higher-valued purposes.…”

Demethylation of Wheat Straw Alkali Lignin for Application in Phenol Formaldehyde Adhesives

“…Most lignin from the forest industry is either burned or directly disposed of in the form of liquid waste [14]. Lignin consists of functional groups exhibiting similar properties to phenol, therefore it is considered the most promising substitute for phenol targeting adhesive applications [15,16]. However, lignin is a large molecular weight polymer with a complex structure [17] which has low reactivity towards formaldehyde.…”