Pretreated unbleached cellulose screen reject for cement-bonded fiberboards

摘要: Unbleached screen reject (USR) is a byproduct widely available from the kraft pulping that rich in cellulose and requires sustainable destination. Therefore, purpose of this work was to determine best condition apply USR as reinforcement cement-bonded fiber boards (CBFBs); using raw or pretreated USRs through water sodium hydroxide immersion followed not by refining. The size distribution, morphology chemical composition were investigated. CBFBs produced following parameters: wood:cement ratio 1:2.75; water:cement 1:2.5; hydration rate 25%; 4 wt% CaCl2 additive (based on cement mass); target density 1.4 g/cm3; thickness 15 mm. Physical mechanical properties USR-containing evaluated. Obtained results indicated consists preserved bundles weakly attached each other. Their main proportion (> 95 wt%) composed particles greater than 20 mesh. refining process slightly affects distribution whereas treatments partially removed lignin precipitates. alkaline pretreatment waste proved be improve composites’ physical properties. Overall, strength higher close commercial products, except for MOR PC. Nonetheless, such challenges could overcome improvements composite’s pretreatments. Thus, industry showed great potential applied CBFBs.