Effect of hydrochloric acid treated neetle fibre on oil absorbency

Hydrochloric acid (HCl) treatment on nettle fibres has been performed to improve the oil absorbency. Box-Behnken experimental design is used to study the influence of parameters, such as treatment time, treatment temperature and concentration on oil absorbency. It is observed that the maximum oil absorbency of 15.39 g/g of nettle fibres is achieved at 2 % of HCl concentration, 75°C of treatment temperature and 60 min of treatment time. Scanning electron microscopic study reveals that the raw nettle fibre surface exhibits waxy and protruding parts, and on HCl treatment the surface becomes rougher. The influence of other parameters such as stirring speed, environmental temperature and reusability on oil absorbency is also studied. Oil sorbed nettle fibres are also subjected to soil burial tests and burning tests. In conclusion, the raw nettle fibres only show an oil absorbency of 9.25 (g/g), whereas HCl treated nettle fibres show a maximum oil absorbency of 15.39 g/g.