Scouring and bleaching process for flax roves using supercritical CO2

In order to solve the problem of high water consumption and environmental pollution in conventional scouring and bleaching process of flax roves, scouring and bleaching technology for flax roves using supercritical CO2 as the medium instead of water was proposed. The effects of mass fraction of compound biological enzymes (xylanase and cellulase), temperature, pressure and time on the whiteness of flax roves were systematically studied using supercritical CO2, and the process conditions of scouring and bleaching were optimized by responsive surface analysis. The influence of the independent variables and their interaction on the whiteness was investigated using Box-Benhnken center composite design and responsive surface method, and the prediction model in a form of quadratic polynomial regression equation was obtained. An optimized process for scouring and bleaching of flax roves was recommended with a mass fraction of compound biological enzymes of 3%, a temperature of 50℃, a pressure of 13 MPa as well as a treatment time of 60 min in supercritical CO2. Moreover, under the optimum technical conditions, the properties of scoured and bleached roves under the supercritical CO2 condition were compared with that of original sample. The whiteness, the residual gum content, the breaking strength, the elongation at break and the split degree of the flax roves are 40.8%, 16.68%, 17.12 cN/tex, 4.23% and 1 072 Nm, respectively. However, there is still a certain gap in comparison with the traditional method, which needs to be further improved. Copyright No content may be reproduced or abridged without authorization.