@article {48055,
	title = {Subcritical water hydrolysis of N-acetyl-D-glucosamine: hydrolysis mechanism, reaction pathways and optimization for selective production of 5-HMF and levulinic acid},
	journal = {Carbohydrate Research},
	volume = {516},
	year = {2022},
	month = {JUN},
	pages = {108560},
	type = {Article},
	abstract = {<p>
	In this study, the subcritical water hydrolysis of N-acetyl-D-glucosamine (NAG), a monomer of abundant renewable marine biopolymer chitin, for production of value-added chemicals is investigated. The enhanced ionization of water at subcritical conditions (200 degrees C; 50-100 bar), provides enough acidity for deacetylation of NAG resulting in 80\% yield of acetic acid along with traces of formic acid, lactic acid, glucose, fructose, 5hydroxymethylfurfural (5-HMF),etc. The significant humin formation indicates that the self-condensation and polymerisation of 5-HMF is favored in water at subcritical conditions. A catalyst p-toluenesulfonic acid (p-TsOH) was employed to selectively convert NAG to levulinic acid (LA) via ring opening of 5-HMF previously formed during hydrolysis. The maximum yield of 27.13 +/- 1\% and 53.46 +/- 1\% of 5-HMF and LA, respectively, was obtained at process conditions optimized using Box-Behnken design coupled with response surface methodology. Subcritical water enables greener conversion of NAG to platform chemicals wherein the selective production can be achieved by tuning the process conditions.</p>
},
	keywords = {5-Hydroxymethylfurfural, chitin, Glucosamine, levulinic acid, Response surface methodology, Subcritical water},
	issn = {0008-6215},
	doi = {10.1016/j.carres.2022.108560},
	author = {Kulkarni, Sphurti Prakash and Dure, Shital N. and Joshi, Sunil S. and V. Pandare, Kiran and Mali, Nilesh A.}
}
