Preparation Of Bacterial Cellulose From Waste Textiles

As we all know,China is both the world's most populous country and the world's largest consumer of textiles,and the huge demand and consumption leads to a large amount of waste textiles every year.To dispose of these tens of thousands of tons of waste,the conventional means are incineration and landfill,but this greatly destabilizes the ecological environment and will have an incalculable impact on the natural world.To solve this growing problem,researchers have proposed recycling methods including mechanical,physical and chemical methods,but the existing recycling methods have low utilization rates and are difficult to handle the huge amount of waste textiles.Bacterial cellulose is a biomaterial derived from microbial fermentation.It has excellent mechanical properties,unique nano-network structure,high purity,high crystallinity,high water-holding capacity,good biocompatibility and degradability,and has abundant applications in food,textile,paper,cosmetics,biomedical and energy fields.However,due to the high production cost,it has been difficult to achieve largescale commercial application of bacterial cellulose.For this reason,several studies have been conducted to treat industrial and agricultural wastes to obtain the raw materials needed for fermentation to prepare bacterial cellulose and thus reduce its production cost.In summary,in this thesis,several inexpensive waste textiles(nylon-6,6,polyester,and wool)were pretreated,and the resulting fabric hydrolysate was used to prepare a medium and inoculated with WT-6 strain to prepare bacterial cellulose after several days of static fermentation.The bacterial cellulose obtained by this method was higher in yield than the conventional HS medium in all cases(2.78 g/L for nylon-6,6hydrolysate medium,2.42 g/L for polyester hydrolysate medium,2.76 g/L for wool hydrolysate medium and 2.28 g/L for HS medium).Subsequently,we characterized the properties of bacterial cellulose prepared from different media and HS media separately,and found that although the various bacterial cellulose samples were obtained from the fermentation of different media,they all shared similar microscopic morphology,chemical group composition,crystal structure,mechanical properties,thermal properties and other properties,which proved that waste textiles are promising low-cost raw materials for the production of bacterial cellulose.It promotes the development of bacterial cellulose toward large-scale commercialization and opens up a new green and efficient way for the recycling of waste textiles.