Lumen Loading : The effects of beating process on tensile index

Lumen-loaded technology has been studied for many years especially by researchers in Pulp and Paper Research Institute of Canada (PAPRICAN) such as Green (1982, 1985), Middleton and Scallan (1985, 1989, 1991) and Van de Van (1994). In 1992, Rioux et. al and Marchessault have proved the suitability of magnetic particles such Fe2O3 and Fe3O4 to use in lumen-loaded process. This study relates to the effects of beating process on tensile index

Adsorption of heavy metal ions on surface of functionalized oil palm empty fruit bunch fibers: single and binary systems

The functionalization of surface charges on oil palm empty fruit bunch (EFB) fibers was modified by grafted carboxylic acid and polymer amine groups. Single and binary adsorption of Cu(II), Ni(II), Mo(VI) and As(V) were investigated by competitiveness in the adsorbents. The mechanism of each metal ion was deliberately studied on kinetics-diffusion (intraparticle diffusion) and isotherm adsorption models (Langmuir and Freundlich). Competitiveness of metal ions was found in the selectivity of Cu(II) > Ni(II) and Mo(VI) > As(V) in the binary solution. The regeneration of adsorbents was performed up to five cycles of an adsorption/desorption process and the reduction of adsorption performance was less than 14.5%. Therefore, this promises low-cost adsorbents for metal ion uptake, showing potential for removal and recovery in industrial wastewater treatment

Direct production of biodiesel from high-acid value Jatropha oil with solid acid catalyst derived from lignin

<p>Abstract</p> <p>Background</p> <p>Solid acid catalyst was prepared from Kraft lignin by chemical activation with phosphoric acid, pyrolysis and sulfuric acid. This catalyst had high acid density as characterized by scanning electron microscope (SEM), energy-dispersive x-ray spectrometry (EDX) and Brunauer, Emmett, and Teller (BET) method analyses. It was further used to catalyze the esterification of oleic acid and one-step conversion of non-pretreated <it>Jatropha </it>oil to biodiesel. The effects of catalyst loading, reaction temperature and oil-to-methanol molar ratio, on the catalytic activity of the esterification were investigated.</p> <p>Results</p> <p>The highest catalytic activity was achieved with a 96.1% esterification rate, and the catalyst can be reused three times with little deactivation under optimized conditions. Biodiesel production from <it>Jatropha </it>oil was studied under such conditions. It was found that 96.3% biodiesel yield from non-pretreated <it>Jatropha </it>oil with high-acid value (12.7 mg KOH/g) could be achieved.</p> <p>Conclusions</p> <p>The catalyst can be easily separated for reuse. This single-step process could be a potential route for biodiesel production from high-acid value oil by simplifying the procedure and reducing costs.</p

Sintesis dan pencirian poli(etilena glikol) bermetoksi-ko-poli(β-amino ester) yang dibentuk daripada heksilamina linear dan siklik sebagai misel polimer

Poli(etilena glikol) bermetoksi-ko-poli(β-amino ester) (MPEG-PbAE) telah disintesis dengan menggunakan poli(etilena glikol) bermetoksi yang mempunyai kumpulan hujung berfungsi akrilat (MPEG-ac), 1,6-heksanadiol diakrilat, heksilamina linear (A) dan heksilamina siklik (B) sebagai bahan reaktan. Kopolimer MPEG-PbAE A dan B dijangka akan membentuk misel dengan MPEG berfungsi sebagai bahagian luar yang hidrofilik dan PbAE yang mempunyai kumpulan heksil berfungsi sebagai bahagian dalam yang hidrofobik. MPEG-ac selepas diubah suai dan kopolimer MPEG-PbAE A dan B selepas disintesis telah dicirikan. Spektroskopi inframerah transformasi Fourier (FT-IR) dan spektroskopi resonans magnet nukleus jenis proton (1H-NMR) telah mengesahkan pengubahsuaian kumpulan hujung hidroksil di MPEG kepada kumpulan hujung akrilat. Didapati kopolimer A adalah lebih sesuai digunakan sebagai pembawa ubat berdasarkan perbandingan antara kopolimer A daripada heksilamina linear dan kopolimer B daripada heksilamina siklik. Kromatografi penelapan gel (GPC) menunjukkan bahawa nombor-purata berat molekul, Mn kopolimer A adalah 11216 dengan indeks kepoliserakan (PDI) 1.1925. Kepekatan misel kritikal (CMC) kopolimer A dalam larutan akueus pH7.4 adalah 84.6 mg/L. Purata saiz misel yang diperoleh daripada analisis penyerakan cahaya dinamik (DLS) adalah 26.25±0.149 nm

Combination of gamma irradiation and sodium carbonate pretreatment on oil palm Empty Fruit Bunch (EFB) for high acidic hydrolysis yield

Oil palm empty fruit bunch (EFB) fibres were pretreated by gamma irradiation followed by sodium carbonate (Na2CO3) before the acid hydrolysis process to produce reducing sugars using diluted sulphuric acid (H2SO4). In this study, EFB fibres were irradiated at different doses, i.e. 0, 100 and 200 kGy. Meanwhile, the gamma irradiated sample were then subjected to Na2CO3 pretreatment with 0 and 5% total titratable alkali (TTA). The effect of the pretreatment using gamma irradiation and Na2CO3 on the physical and chemical properties of the EFB fibres and the yield of the reducing sugar obtained from the acid hydrolysis process was investigated. The obtained results showed that the content of holocellulose was increased significantly with the increase of irradiation doses combined with Na2CO3 pretreatment, whereas lignin content of the EFB was decreased. The gamma irradiation and Na2CO3 pretreatment resulted in structure breakage and removal of silica of EFB fibres which can be due to the swelling of the fibres. A synergistic effect between gamma irradiation and Na2CO3 was observed, in which the yield of reducing sugars was increased by combining the gamma irradiation and Na2CO3 pretreatment

Isolation and fractionation of cellulose nanocrystals from kenaf core

In this study, cellulose nanocrystals (CNC) were produced using acid hydrolysis method. Kenaf core was pretreated with 4 wt. % sodium hydroxide (NaOH), followed by bleaching using 1.7 wt. % sodium chlorite (NaClO2) in acetate buffer. The bleached fiber was acid hydrolyzed for 45 and 55 min using 64 wt. % sulfuric acid (H2SO4). The size distribution of the CNC segregated via differential centrifugation with different speed was also investigated. The CNC suspension obtained was centrifuged at 3000, 6000, 9000 and 12000 rpm. The resultant CNC suspension collected was characterized using Fourier transform infrared (FTIR) analysis, X-ray diffraction (XRD) and transmission electron microscopy (TEM). FTIR results showed the progressive removal of non-cellulosic constituents for each subsequent treatment. It also showed that the CNC produced after hydrolysing for 55 min has the highest degree of crystallinity (81.15%). CNC produced from acid hydrolysis process of 45 min have lengths between 50 and 270 nm while CNC produced from acid hydrolysis process of 55 min have length around 40 to 370 nm

Effects of physical treatments on the hydrophobicity of kenaf whole stem paper surface using stearic acid.

Kenaf (Hibiscus cannabinus L.) is a relatively new industrial crop which has been identified as an alternative source of fiber in the papermaking industry in Malaysia. In this study, experimental unbleached kenaf kraft paper samples were used as a substrate to produce water-resistant paper by employing a special coating. In the preparation of the coating formulation, commercially precipitated calcium carbonate (PCC) was used as the filler, in addition to 0 to 0.32 w/w g of hydrophobic stearic acid (SA). Polymer latex (PL) was added at 0.4 to 0.16 w/w g into the coating compound to control the surface roughness of the samples. The paper morphology was examined by employing a scanning electron microscope (SEM). Hydrophobic kenaf kraft paper prepared in this study had water contact angle (θ) greater than 90°. Hydrophobic paper made with formulation PL4c resulted in the highest value contact angle of 147°. The process of surface coating by dipping increased the water contact angle and this treated paper achieved a high hydrophobic level. For mechanical properties, the coated kenaf paper showed decreasing tensile strength as the addition of stearic acid increased

Chemical and thermal properties of purified kenaf core and oil palm empty fruit bunch lignin

Chemical and thermal properties of pure lignin are depending on the plant origin, extraction method and type of lignocellulosic. In this study, lignin from oil palm empty fruit bunch (EFB) and kenaf core were recovered from soda black liquor by two steps of acid precipitation with hydrochloric acid and followed by soxhlet with n-hexane. The XRD analysis of purified EFB lignin (EAL) and purified kenaf core lignin (KAL) exhibited amorphous properties, similar to the standard alkali lignin (SAL). The FTIR and Raman spectra showed that all samples consist of HGS unit. In FTIR, the syringyl unit is assigned at (1125 cm-1), (1327 and 1121 cm-1) and (1326 and 1117 cm-1) meanwhile the guaicyl unit is assigned at (1263, 1212 and 1028 cm-1), (1271, 1217 and 1028 cm-1) and (1270, 1211 and 1030 cm-1) for SAL, EAL and KAL, respectively. The peak around 1160 cm-1 represents C-O stretching of conjugated ester group present in HGS lignin. As for Raman, the HGS unit exists in the range of 1100-1400 cm-1. Among the purified samples, the TGA result showed that KAL has a better thermal stability with the residue of 36.49% and higher Tg value which is 152.69°C

Highly porous chitosan beads embedded with silver-graphene oxide nanocomposites for antibacterial application

Incorporation of silver nanomaterial into polymer matrix can further accomplished their potential usage in real life applications. In our previous study, silver nanoparticles (AgNPs) and silver-graphene oxide nanocomposites (AgGO) were prepared via a rapid microwave-assisted method. Hereby, the as-synthesized AgNPs or AgGO was dispersed in a chitosan solution. Subsequently, the resultant mixture solution was further coagulated in a coagulation bath containing sodium hydroxide via a neutralization process. This resulted in the formation of spherical-shaped chitosan beads. The structure of the beads showed that the chitosan beads embedded with AgGO exhibited a more porous structure as compared to the plain chitosan beads. Furthermore, the chitosan beads containing AgNPs or AgGO were tested for their antibacterial activity against Escherichia coli and Staphylococcus aureus. The antibacterial results indicated that the silver nanomaterial contained chitosan beads could effectively inhibit the growth of both E. coli and S. aureus as compared to the bare chitosan beads. The produced chitosan nanocomposite envisioned that can be potentially employed for water disinfection purpose

Preparation of transition metal sulfide nanoparticles via hydrothermal route

Nano sized copper sulfide, iron sulfide and molybdenum sulfide were successfully synthesised via a simple hydrothermal method. Sodium thiosulfate pentahydrate (Na2S2O3¥5H2O) and hydroxylamine sulfate ((H3NO)2¥H2SO4) were used as the starting materials and reacted with the transition metal source at 200oC for 90 min. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and Fourier transform infrared spectroscopy (FTIR). Spherical shape CuS and FeS2 nanoparticles with high crystallinity were successfully produced. The transmission electron micrographs revealed the well-dispersibility of the produced nanoparticles. Scanning electron micrograph showed the MoS2 nanoparticles possessed a spherical shape with sheet-like structure covering on the outer surface of the particles