| 摘要 |
<p>The invention discloses a novel process for conversion of grey acrylic fiber waste to acrylic powder comprising of the steps of (a) dissolving the acrylic wastes in solvents such as N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), dimethylacetamide (DMAc), aqueous solution of sodium thiocyanate (NaSCN)) but not limited to above mentioned solvents in the concentration of 1-25% and temperature of not more than 90°C; (b) filtration through any coarse filter media to remove any un-dissolved and other impurities before precipitation; (c) precipitation of acrylic polymer from the solution using any commercially available primary-, secondary- and tertiary alcohols in the ratio of 1:1 to 1:10 volume by volume of polymer solution and alcohols; (d) vacuum filtration to remove the solvents mixture; (e) dispersing the polymer in hot/cold DM water in the ratio of 1:5 to 1:20 weight by volume to remove residual solvents; (e) palletizing the wet precipitate before drying or directly drying the polymer at elevated temperature to remove moisture; (f) pulverizing the dried polymer and sieving to obtain fine acrylic powder; (g) recovering the used solvents by distillation process.</p> |
