Search

In this study, Box-Behnken design (BBD) and response surface methodology (RSM) was applied to study the effects of alkaline peroxide treatment variables (cooking time, sodium hydroxide concentrations, and hydrogen peroxide concentrations) on the pulp and paper strength properties (screened pulp yield, kappa number, tensile index, tear index, burst index), which are considered dependent variables or response variable of the extracted cellulose from oil palm (Elaeisguineensis) fronds (OPF) vascular bundle fibers. The results indicated that at the optimum operating conditions of 2.35% NaOH, 5.00% H2O2 and a 53.41 min cooking time, resulting maximum strength properties (tensile index, burst index, tear index,) gave 9.92 Nm/g, 6.55 KPam2/g, 6.22 mNm2/g, respectively. The study revealed that alkaline peroxide pulped fibers of oil palm frond vascular bundles could be considered a suitable alternative for paper qualities with moderate strength requirements.

Treatment of the abundant oil palm empty fruit bunches with alkaline peroxide chemicals and subsequent fibrillation at varying mechanical energies resulted in favourable morphological changes of the generated fibers. The produced fibrous mass composed of intensely fibrillated elements ranging from micro to nanodiameter fibrils. nanofibrils and webs of nanofibrils were factors contributing to the functionality of the fibrous mass as fibre web augmentation elements. Profound improvement in fiber network is particularly attributable to the ability of the collected elements to fill up inter-fiber gaps and this was attributable to the micro elements in the form of micro fines, segmented micro-fibrils and webs of nanofibrils. The uniquely generated thin layers of nanofibril webs (TN-webs), were found to increase fiber web density by gluing multiple layers of fibers, together. Having landed on the surface of micro-fiber web, these TN-webs were identified as responsible for the masking effects of the underlying micro-fibres. Under such condition, fibers were observed to coalesce, suggesting also an augmented fiber network as evident from the 130% increase in tensile index and a 450% enhancement in burst index of the resultant fiber web relative to those formed with the basic alkaline peroxide chemical-mechanical refining (CMR) synergy. This reveals a great promise to EFB for application as super-strong fibre-web materials such as packaging and specialty paper-based products.

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.

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.

Papers produced from oil palm empty fruit bunches (EFB) via Alkaline Peroxide Pulping (APP) was preceded by three main steps; dewaxing of EFB, alkaline peroxide (AP) impregnation into EFB and refining of biomass to generate pulp. The experiment was carried by varying chemical level and number of impregnation stages. For 2:2.5% AP level, two-stage impregnation improved hand sheets tear index by 45%, 164% boost in tensile index, 26% enhancement in zero span index and more than 5% in burst index. By applying 8:10% AP level, significant improvements were gained at the third and fourth stages of AP impregnation. Although there was no significant change in hand sheet strength with multiple impregnation for 4:5% AP level, improvement in brightness of hand sheets was apparent, analogous to the effect of increasing AP level. The found paper properties development show that alkaline peroxide pulping of EFB could be adapted to various targeted properties by adjustment of AP level and impregnation stages.

EFB (empty fruit bunch) was subjected to alkaline peroxide pulping for generation of fibrous mass as raw material for the making of pulp-based products. During refining, co-produced fines were collected by fractionation on square-mesh screens of 200-, 250-, 300- and 400- mesh sizes, placed at the refining discharge by order of increasing mesh. Each set of the produced paper was incorporated with 12% fines for microscopic analysis. It appears that sheared vessel elements and fibrils were predominant and they make up the mass rendering collapsibility of cell wall for good product formation. The study acknowledged the form of fines functioning as natural filler in pulp network and worthy of utilization for reduction of total suspended solid.

The pulp extracted from the alkaline peroxide pulping (APP) of EFB was beaten from 500 revolutions to 10000 revolutions using PFI mill to investigate the morphological changes undergone by the pulp and the resultant effect on paper sheet properties. As a result of beating, pulp elements were observed as intensely fibrillated, reducing the amounts of fibre bundles and thus, reducing interruption in the inter-fiber bonding. To a defined extent, beating was also seen as unwinding the structure of vessel element to a single strand of loose spiral body. These fibrillated vessel elements of APP pulp from EFB, plus the fines element germinating from further segmentation of the vessels, were the factors contributing to the overall strength improvement of the produced EFB pulp network. The applied increment in beating revolution had apparently widened the known broad spectrum quality of APP pulp from EFB. This demonstrates EFB potential for application in specialty paper production.