nanofibrillation of the oil palm empty fruit bunches, EFB, by synergizing the alkaline peroxide chemicals and a subsequent refining process was found to liberate useful fibrous mass. Of these, the nanofiber web materials were found to render smoothing effect by covering the trough between bound fibers and thus, hiding the true morphology of fibers on the paper surface. Apart from smoothing, which is one of the important paper properties requiring expensive furnishing, the thin nanofiber webs (tn-webs) also held the paper structure firmly by plunging of the nanofibers into the gaps between the micro-fibers. This is mainly due to their dimensional (10 nm < Diameter < 100 nm) compatibility. The smorgasbord shapes of the liberated tn-webs have a relatively lighter structures, found in the range of 2400-121500 μm2 areas, could be abundantly produced by adjustment of refiner blade type with a specific alkaline peroxide chemical level. The maximal level of paper smoothness was measured by the laser toner spread (fusion or otherwise). Analysis reveals more extensive toner fusion on Waldron-4 sample, suggesting surface uniformity anfd better leveling of fibers on paper surface. It turns out that, this corresponds to the fibers detected with more evidence of delamination and thus, more count of nanofiber web. Not only is this a proof of correlation of nanofiber web intensity with paper smoothness but also a possible promise for an alternative measure for paper printability enhancement.

Pulp from the oil palm empty fruit bunches (EFB) was extracted via Alkaline Peroxide Pulping (APP). The pulping process was conducted through three main steps; dewaxing of EFB, impregnation of alkaline peroxide (AP) into EFB and refining of biomass to finally produce the pulp. The varying peroxide levels and number of impregnation stages were found to affect the refining energy consumption and the properties of the resultant pulp and paper. Diagnosis by electron microscopic imaging revealed a strong correlation between paper properties development and paper surface morphologies. By multiplying the stages of the low alkaline peroxide level (2:2.5% AP) impregnation, refining energy could be reduced by 30% while improving brightness and paper mechanical properties. Higher alkaline peroxide level (4:5% AP) could reduce the refining energy by 50% while still improving brightness. Beyond these AP levels (8:10% AP), refining energy could be reduced by 67% by increasing the number of impregnation stages, with positive effects on brightness and paper mechanical properties. The findings suggest that increasing the AP impregnation stages had exposed more active sites to react with AP. The enhanced AP accessibility to EFB structures facilitated mechanical fibrillation of EFB vascular bundles through the refining process. The proper synergy between AP and the adopted mechanical refining was the factor that triggered the liberation of nanocells from EFB biomass and this had ultimately improved paper properties.

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The increasing popularity of the oil palm empty fruit bunches (EFB) as a source of non-wood fibre has prompted a variety of research on processing and utilisation of the material. In an attempt to define the characters, reusability and end-of-life, oil palm EFB was processed by the alkaline peroxide variable treatment (APVT) systems. Low synergy between alkaline peroxide (AP) chemical and mechanical fibrillation through fibrillation (CMR synergy) revealed the yield of segments of EFB vascular bundles while heightening the mechanical forces further, generated more uniform but a mixture of fiber and segments of fibre bundles. An intermediate CMR synergy generated fibres forming a more well-defined but a rough resultant fibre network due to partial fibrillation of the vascular bundle. Applying maximal CMR synergy was found to generate higher yield of network strengthening fibrous cells. These were later identified as nanoscale fiber network or nanoscan, consisting of 10-80 nm diameter fibers arranging themselves in a systematic network. Analysis of the polarity of fibers harvested from the APVT systems manifests the systematic construction of nanofibrils winding in helical manner to form arrays of nanofibres that glue themselves together as micro-fibrils. Interconnections between fibers and other gluing elements led to the vascular bundle known as the EFB biomass that was once dross and that can now be marvelled as an alternative source of nanofibers for the nanoindustry sector.