The potential of cashew nut shell waste in charcoal briquettes after producing cashew nut shell liquid through cold extraction
Siwalak Pathaveerat, Pimpan Pruengam, Nonglak Lekrungroenggid
Abstract
Cashew nut shell liquid (CNSL), extracted without chemicals or high temperatures, primarily contains phenolic compounds and is used in pharmaceuticals and special polymers. This study assesses a cold extraction process for CNSL at press forces of 200, 250, and 275 kg/cm2 and holding times of 1, 2, and 5 min, achieving a maximum yield of 35.98 %, with holding time having minimal impact. The waste from cashew nut shells was carbonized to produce briquettes, enhancing their heating value. Briquettes were made from carbonized cashew nut shells and rice husks in various proportions, using cassava flour as a binder. Analysis of the briquettes' properties showed that the CNS amount significantly influenced calorific value and thermal efficiency, with rice husk charcoal mixtures improving stability and compressive strength. The recommended charcoal briquette from CNS, rice husk and cassava flour which is the ratio 7:3:1 by weight (recipe E), providing high compressive strength and calorific value similar to briquettes made solely from cashew nut shells (recipe A). This research supports converting CNS waste into industrial products and renewable energy.