Esterification of bagasse cellulose with metal salts as efficient catalyst in mechanical activation-assisted solid phase reaction system
The present study focused on investigating the catalytic mechanism of metal salts (sodium hypophosphite, sodium bisulfate and ammonium ferric sulfate) for esterification of bagasse cellulose carried out by mechanical activation-assisted solid phase reaction in a stirring ball mill. FTIR analysis of the products confirmed that these metal salts could catalyze the esterification of cellulose. XRD, SEM, FTIR, and 31P-NMR analyses of different samples indicated a synergistic effect between metal salt and ball milling, and the presence of metal salts enhanced the destruction on crystal structure of cellulose by mechanical force. The catalytic mechanism of three metal salts was difference: sodium bisulfate and ammonium ferric sulfate belonged to the catalytic mechanism of protonic acid and Lewis acid, respectively, while the catalytic mechanism of sodium hypophosphite was considered as that it could react with maleic acid to form active intermediates under ball milling.
KeywordsCellulose Esterification Metal salt Catalytic mechanism Mechanical activation
This research was supported by National Natural Science Foundation of China (Nos. 51463003 and 21666005), the Guangxi Science and Technology Plan Project of China (Grant No. AB16380305), Guangxi Distinguished Experts Special Foundation of China, and the Scientific Research Foundation of Guangxi University (Grant No. XJPZ160713).
- Chundawat SPS, Bellesia G, Uppugundla N, Da Costa Sousa L, Gao D, Cheh AM, Agarwal UP, Bianchetti CM, Phillips GN, Langan P, Balan V, Gnanakaran S, Dale BE (2011) Restructuring the crystalline cellulose hydrogen bond network enhances its depolymerization rate. J Am Chem Soc 133(29):11163–11174CrossRefGoogle Scholar
- Hu H, Li H, Zhang Y, Chen Y, Huang Z, Huang A, Zhu Y, Qin X, Lin B (2015) Green mechanical activation-assisted solid phase synthesis of cellulose esters using a co-reactant: effect of chain length of fatty acids on reaction efficiency and structure properties of products. RSC Adv 5(27):20656–20662CrossRefGoogle Scholar
- James SL, Adams CJ, Bolm C, Braga D, Collier P, Friscic T, Grepioni F, Harris KD, Hyett G, Jones W, Krebs A, Mack J, Maini L, Orpen AG, Parkin IP, Shearouse WC, Steed JW, Waddell DC (2012) Mechanochemistry: opportunities for new and cleaner synthesis. Chem Soc Rev 41(1):413–447CrossRefGoogle Scholar
- Rowell RM (1994) Acetyl distribution in acetylated whole wood and reactivity of isolated wood cell-wall components to acetic anhydried. Wood Fiber Sci 26(1):11–18Google Scholar