title: Fabrication of hydrophobic polymer foams with double acid sites on surface of macropore for conversion of carbohydrate.
abstract: Herein we reported a simple and novel synthetic strategy for the fabrication of two kinds of hydrophobic polymer foam catalysts (i.e. Cr(3+)-HPFs-1-H(+) and HPFs-1-H(+)) with hierarchical porous structure, inhomogeneous acidic composition and Lewis-Brønsted double acid sites distributed on the surface, which was used to one-pot conversion of carbohydrate (such as cellulose, glucose and fructose) to a key chemical platform (i.e. 5-hydroxymethylfurfural, HMF). The water-in-oil (W/O) high internal phase emulsions (HIPEs), stabilized by both Span 80 and acidic prepolymers as analogous particles offered the acidic actives, were used as the template for simultaneous polymerization of oil phase in the presence of divinylbenzene (DVB) and styrene (St). After subsequent ion-exchange process, Lewis and Brønsted acid sites derived from exchanged Cr(3+) and H(+) ion were both fixed on the surface of cell of the catalysts. The HPFs-1-H(+) and Cr(3+)-HPFs-1-H(+) had similar hierarchical porous, hydrophobic surface and acid sites (HPFs-1-H(+) with macropores ranging from 0.1 μm to 20 μm, uniform mesopores in 14.4 nm, water contact angle of 122° and 0.614 mmolg(-1) of Brønsted acid sites, as well as Cr(3+)-HPFs-1-H(+) with macropores ranging from 0.1 μm to 20 μm, uniform mesopores in 13.3 nm, water contact angle of 136° and 0.638 mmolg(-1) of Lewis-Brønsted acid sites). It was confirmed that Lewis acid sites of catalyst had a slight influence on the HMF yield of fructose came from the function of Brønsted acid sites, and Lewis acid sites were in favor of improving the HMF yield from cellulose and glucose. This work opens up a simple and novel route to synthesize multifunctional polymeric catalysts for efficient one-pot conversion of carbohydrate to HMF.
authors.affiliation: School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China. Electronic address: pjm@ujs.edu.cn.
authors.forename: Jianming
authors.initials: J
authors.lastname: Pan
authors.affiliation: School of Municipal and Environmental Engineering, Henan University of Urban Construction, Pingdingshan 467036, China.
authors.forename: Yanli
authors.initials: Y
authors.lastname: Mao
authors.affiliation: School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China.
authors.forename: Heping
authors.initials: H
authors.lastname: Gao
authors.affiliation: Oak Ridge National Laboratory, TN 37831, United States. Electronic address: xiongq@ornl.gov.
authors.forename: Qingang
authors.initials: Q
authors.lastname: Xiong
authors.affiliation: School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Fengxian
authors.initials: F
authors.lastname: Qiu
authors.affiliation: School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China.
authors.forename: Xiangheng
authors.initials: X
authors.lastname: Niu
mesh_terms: D002384:Catalysis; D002482:Cellulose / Q000737:chemistry; D002857:Chromium / Q000737:chemistry; D005632:Fructose / Q000737:chemistry; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D005947:Glucose / Q000737:chemistry; D007474:Ion Exchange; D058116:Lewis Acids / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D016062:Porosity; D017550:Spectroscopy, Fourier Transform Infrared; D020058:Styrene / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry
chemical_list: D058116:Lewis Acids; D011108:Polymers; D014753:Vinyl Compounds; D002857:Chromium; D005632:Fructose; D020058:Styrene; C008046:5-hydroxymethylfurfural; D002482:Cellulose; D005662:Furaldehyde; D005947:Glucose; C004985:divinyl benzene
keywords: Carbohydrate to HMF; Hierarchical porous structure; High internal phase emulsions (HIPEs); Hydrophobic polymer foam (HPFs); Lewis–Brønsted acid