USTC Yushu Hong team prepared novel solid acid catalyst material nanofiber
April 2019, University of Science and Technology of China Yushu Hong research team working in the series based on the previous use of biomass preparation of functional bacterial cellulose carbon-based material on the development of a simple, effective, macro production technology, prepared a new type of solid acid catalysts nanofiber material and of such depth exploration prospect nanofiber solid acid catalyst in several important industrial chemical catalysis, research related to \”Natural nanofibrous Cellulose-derived solid acid catalysts\” was published in Research (Research, Doi: 10.34133 / 2019/6262719) on. Because of safety, green, less corrosive, easy recovery and many other advantages, the solid acid catalyst (SACs) gradually replaced the conventional liquid acid catalyst plays an important role in various chemical production. At present solid acid catalyst has become an important research direction of acid catalysis, it has been widespread concern researchers. Presence of a low acid density, poor stability, high catalytic performance and cost disadvantages of the conventional need for the improvement of SACs. In recent years, researchers have developed a series of new SACs, and show a good prospect. The more prominent carbohydrate Tokyo Institute of Technology Development Hara et derived sulfonated carbon-based material, such solid acid catalysts exhibit a hydrophilic reaction good catalytic performance. However, such materials, low porosity and specific surface area, which restricts the application in a hydrophobic reaction. Thus, the development of high SO3H site, nanostructured porous carbon-based material and high specific surface area, to ensure simultaneously both for hydrophilic and hydrophobic interaction, also applicable to other important new SACs reaction is very urgent. But so far this is still a huge challenge. Recently, University of Science and Technology of China Professor Lianghai Wei Yu Shuhong research team developed a new type of porous carbon-based SACs, the material is prepared (FIG. 1) by the incomplete carbonization and sulfonation natural nanocellulose. As the preparation process is simple, low cost, it is easy to promote the use. More importantly, the retention SACs prepared three-dimensional network structure of the natural fiber precursor fiber having a high specific surface area (up to 837 m2 · g-1) and a large pore volume (up to 0.92 cm2 · g-1). In addition, efficient sulfonation process nanofiber has a rich Br? Nsted acid sites, including -SO3H groups (up to 2.42 mmol · g-1) and hydroxy (-OH) and carboxyl (-COOH) group group (total acid density of up to 3.88 mmol · g-1). process diagram (a) Preparation of (b) BC (c) large scale preparation of aerogels BC-CNFS nanofiber solid acid catalyst (d), SEM image and (e) TEM element image distribution image in a series of individual fibers and significant acid-catalyzed reactions, including α- methyl styrene dimerization (hydrophobic reactions, see Table 1), the esterification of oleic acid (hydrophilic reaction ) and pinacol rearrangement reaction (strong acid dependent response), the performance of the new SACs are much better than general solid acid catalyst present, and even in some cases better performance than the classical liquid acid catalyst is H2SO4. Furthermore, the other important novel reaction SACs also exhibits superior performance, such as synthetic and ketene nitrophenyl β- / ester reduction. TABLE 1 Comparative Performance nanocatalytic α- catalyst performance fibers and a solid acid catalyst methylstyrene dimerization conventional solid acid and a liquid acid This work demonstrates the preparation of efficient use of biomass bacterial cellulose nanofiber solid acid catalysts . The development of new nano-fiber SACs for their preparation process is simple, inexpensive and easy to get raw materials, can achieve large-scale production, is expected to promote the use in the chemical industry. In addition, the methodology can be extended to more affordable wood fiber-based nano-prepared and efficient new SACs, but also extended to other SACs system, such as phosphorylation SACs and so on. The work on sustainable and efficient catalyst to provide a new idea for further development based on nano-structured biomass material green.