Gallardo-Sánchez Manuel Alberto, Diaz-Vidal Tania, Navarro-Hermosillo Alejandra Berenice, Figueroa-Ochoa Edgar Benjamin, Ramirez Casillas Rogelio, Anzaldo Hernández José, Rosales-Rivera Luis Carlos, Soltero Martínez J Felix Armando, García Enríquez Salvador, Macías-Balleza Emma Rebeca
Departamento de Ingeniería de Proyectos, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara C.P. 44430, Mexico.
Departamento de Ingeniería Química, Centro Universitario de Ciencias Exactas e Ingenierías, Universidad de Guadalajara, Guadalajara C.P. 44430, Mexico.
Nanomaterials (Basel). 2021 Feb 18;11(2):520. doi: 10.3390/nano11020520.
A multilevel factorial design of 2 with 12 experiments was developed for the preparation of cellulose nanocrystals (CNC) from Weber var. Azul bagasse, an agro-industrial waste from tequila production. The studied parameters were acid type (HSO and HCl), acid concentration (60 and 65 wt% for HSO, 2 and 8N for HCl) temperature (40 and 60 °C for HSO, 50 and 90 °C for HCl), and hydrolysis time (40, 55 and 70 min for HSO; and 30, 115 and 200 min for HCl). The obtained CNC were physical and chemically characterized using dynamic light scattering (DLS), atomic force microscopy (AFM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XDR) techniques. The maximum CNC yield was 90 and 96% for HCL and HSO, respectively, and the crystallinity values ranged from 88-91%. The size and morphology of CNC strongly depends on the acid type and hydrolysis time. The shortest CNC obtained with HSO (65 wt%, 40 °C, and 70 min) had a length of 137 ± 68 nm, width 33 ± 7 nm, and height 9.1 nm, whereas the shortest CNC obtained with HCl (2 N, 50 °C and 30 min) had a length of 216 ± 73 nm, width 69 ± 17 nm, and height 8.9 nm. In general, the obtained CNC had an ellipsoidal shape, whereas CNC prepared from HSO were shorter and thinner than those obtained with HCl. The total sulfate group content of CNC obtained with HSO increased with time, temperature, and acid concentration, exhibiting an exponential behavior of CSG=aebt.
采用二级二水平析因设计，进行了12次实验，以龙舌兰酒生产过程中的农业工业废弃物——韦伯变种蓝甘蔗渣为原料制备纤维素纳米晶体（CNC）。研究的参数包括酸的类型（H₂SO₄和HCl）、酸浓度（H₂SO₄为60%和65%重量，HCl为2N和8N）、温度（H₂SO₄为40℃和60℃，HCl为50℃和90℃）以及水解时间（H₂SO₄为40、55和70分钟；HCl为30、115和200分钟）。使用动态光散射（DLS）、原子力显微镜（AFM）、傅里叶变换红外光谱（FT-IR）、X射线光电子能谱（XPS）和X射线衍射（XDR）技术对所得的CNC进行物理和化学表征。HCl和H₂SO₄得到的CNC最大产率分别为90%和96%，结晶度值在88 - 91%之间。CNC的尺寸和形态强烈依赖于酸的类型和水解时间。用H₂SO₄（65%重量，40℃，70分钟）得到的最短CNC长度为137±68纳米，宽度为33±7纳米，高度为9.1纳米，而用HCl（2N，50℃和30分钟）得到的最短CNC长度为216±73纳米，宽度为69±17纳米，高度为8.9纳米。一般来说，所得的CNC呈椭圆形，而由H₂SO₄制备的CNC比用HCl制备的更短更细。用H₂SO₄得到的CNC的总硫酸根含量随时间、温度和酸浓度增加，呈现出CSG = aebt的指数行为。
