The current focus of wood preservation research is on developing wood preservatives from natural and environmentally compatible compounds for industrial application. Liquefaction of wood is one of the promising approaches to utilize woody waste where the wood powder is converted into a chemically active liquid with the help of a liquefying agent like phenol, cresol, plant-based solvent as CNSL and Cardanol. These Liquefied wood polyols and conventional wood preservatives like CCA, CCB, and Chlorpyriphos as synthetic chemicals were in use for a long time and used in prescribed proportion. The efficacy and economic suitability of liquefied wood as a wood preservative and conventional wood preservative against termite and fungi have been studied. Wood samples were impregnated with both conventional and liquefied wood preservatives and evaluated as per Bureau of Indian Standards (BIS) in terms of its antifungal (IS 4873, Part I:2008) and termiticidal activities (IS 4833:1993) through accelerated termite graveyard test and fungal resistance test. The level of impregnation of liquefied wood in wood was estimated by determining the weight percent gain. In the graveyard test, samples were periodically observed weekly intervals. The results indicated that Samples treated with phenol, CNSL, Cardanol based liquefied wood polyols exhibited better results as compared to conventional synthetic wood preservatives both in visual observation and percentage weight loss as compared to initial condition and untreated control samples. The percentage weight loss of liquefied wood polyols (phenol, CNSL and cardanol individually) treated wood sample was ranging from only 5-20% of its initial weight; wood treated with preservatives (CCA, CCB, and chlorpyriphos) shows % weight loss varied from 40- 60% and did not exhibit better resistance against termite and fungi as compared to the untreated samples. The treated samples were also exposed to fungus for 16 weeks. The fungicidal traits of liquefied wood polyols (phenolated, CNSL, and cardanol individually) treated wood showed higher antifungal efficacy against both white rot and brown rot of wood, conventionally wood treated preservatives (CCA, CCB, and chlorpyriphos) shows low efficacy against termite and fungus. The utilization of liquefied wood polyols for timber protection against termite and fungi as one of suitable option for valorizations of wood waste which is being generated during primary & secondary processing of wood by wood-based industry in large scale. The liquefied wood polyols (CNSL & Cardanol) based proved as the best wood preservative among all categories and having potential for commercialization over conventional wood preservatives at large scale by wood-based industry.

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