The hydrothermal carbonization (HTC) of waste cotton fibers, viscose fibers and Avicel to prepare carbon microspheres was investigated. The precursors and carbonized products were characterized by SEM, EDS, XRD, TG and FTIR. Results showed that the optimum HTC conditions for preparing carbon microspheres from cotton fibers and Avicel with high crystallinities of 60.35% and 60.24%, respectively, were respectively 330^oC for 6 h in 0.15% CuSO₄ and at 310^oC for 6 h in 0.10% CuSO₄, while they could be synthesized at 260^oCfor 8 h from viscose fibers with a low crystallinity of 34.31% without any additive, indicating that cellulosic materials with a lower crystallinity have milder HTC conditions for preparing carbon microspheres. The polymerization degree of the cellulosic materials has little effect on the formation of carbon microspheres. The carbon microspheres produced from three cellulosic materials have a similar amorphous structure and abundant functional groups, while those produced from cotton fibers and Avicel have higher carbon contents and better thermal stability. The cellulosic materials were first hydrolyzed to form water soluble products, which underwent dehydration, polymerization, polycondensation and aromatization to form the carbon microspheres. CuSO₄ promotes the hydrolysis of the cellulosic materials which is why it is needed to form carbon microspheres from cellulose of a high crystallinity.

研究了废棉纤维，粘胶纤维和Avicel的水热碳化工艺，以制备碳微球。通过SEM，EDS，XRD，TG和FTIR对前驱体和碳化产物进行了表征。结果表明，由高结晶度分别为60.35％和60.24％的棉纤维和Avicel制备碳微球的最佳HTC条件分别为：在0.15％CuSO _4中的330 ^o C持续6 h和在310 ^o C的310 ^o C持续6 h。 0.10％CuSO ₄，而它们可以在260 ^o下合成在没有任何添加剂的情况下，由低结晶度的34.31％的粘胶纤维经C加热8小时，表明具有较低结晶度的纤维素材料具有较温和的HTC条件，可用于制备碳微球。纤维素材料的聚合度对碳微球的形成影响很小。由三种纤维素材料生产的碳微球具有相似的无定形结构和丰富的官能团，而由棉纤维和Avicel生产的碳微球具有更高的碳含量和更好的热稳定性。首先将纤维素材料水解形成水溶性产物，然后将其脱水，聚合，缩聚和芳构化，以形成碳微球。硫酸铜₄ 促进纤维素材料的水解，这就是为什么需要由高结晶度的纤维素形成碳微球的原因。