Tar-free and Benzo[a]pyrene-free Hydrothermal Liquefaction of Bamboo and Antibacterial Property of Recovered Vinegar

Bamboo, which was treated using superheated steam controlled at a low temperature range, gave tar-free and benzo[a]pyrene-free vinegar. The vinegar’s selective antibacterial activity against Staphylococcus aureus concerned with the atopic dermatitis and Bacillus cereus causing food poisoning in humans was confirmed, while no effect was found against Escherichia coli and Bacillus subtilis as being indigenous bacteria in natural environments

Short Bamboo Fibers Coated by Lignin during Super-Heated Steam Treatment and Bio-composites using Same

In order to apply short bamboo fiber (sBF) as a functional reinforcement of bio-composites having specific electrical properties, lignin-surfaced sBF was prepared via super-heated steam (SHS) treatment of bamboo. The sBF was easily isolated from the intrinsic fibrovascular bundle structure of bamboo after SHS treatment and pulverization. The isolated sBF was surfaced by brown-colored hydrophobic compounds, which were lignin-derived compounds generated during the SHS treatment. The functional bio-composites were prepared from the SHS-treated sBF and polypropylene and showed specific antistatic properties. Surface electrical resistance values of the composites decreased significantly with increase in the aspect ratio (AR) value of sBF. It is considered that the lignin-derived surfacing of sBF functions as an electron carrier in the composite, in particular, the longer sBF acts as an effective bridge for transporting electrons over long distances along conductive paths. From a cross-sectional microscopic image of the bio-composite, orientated sBFs were observed in its surface layer, supporting the suggestion of conductive path formation. Further, it was confirmed that the reinforcing effect of the presence of sBF was increased with increasing AR value

Tar-free and benzo[a]pyrene-free hydrothermal liquefaction of bamboo and antibacterial property of recovered vinegar

Bamboo, which was treated using superheated steam controlled at a low temperature range, gave tar-free and benzo[a]pyrene-free vinegar. The vinegar’s selective antibacterial activity against Staphylococcus aureus concerned with the atopic dermatitis and Bacillus cereus causing food poisoning in humans was confirmed, while no effect was found against Escherichia coli and Bacillus subtilis as being indigenous bacteria in natural environments

Development of conceptual design of car housing side mirror using intergrated approach

This paper presents the development of automotive car housing side mirror using integrated approach. The car housing side mirror was chosen to illustrate the application of integrated approach. Various product development stages were conducted which initially from market investigation to concept development stage. Conceptual design stage is a main design stage which is analytical hierarchy process (AHP) was selected as a decision making method to determine the most appropriate design concept. Finite Element Analysis (FEA) was employed to analysis design based on static analysis for determining the strength and performance of the design. The result shows design concept 3 (DC-3) is the preferred choice since it has the highest value among the five alternatives with a value of 0.4701 (47%)

Isolation and characterization of nanocrystalline cellulose from roselle-derived microcrystalline cellulose

Roselle fiber is a renewable and sustainable agricultural waste enriched with cellulose polysaccharides. The isolation of Nanocrystalline cellulose (NCC) from roselle-derived microcrystalline cellulose (MCC) is an alternative approach to recover the agricultural roselle plant residue. In the present study, acid hydrolysis with different reaction time was carried out to degrade the roselle-derived MCC to form NCC. The characterizations of isolated NCC were conducted through Fourier Transform Infrared Ray (FTIR), Transmission Electron Microscopy (TEM), Field Emission Scanning Electron Microscopy (FESEM), Atomic Force Microscopy (AFM), Dynamic Light Scattering (DLS), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). As evaluated from the performed morphological investigations, the needle-like shape NCC nanostructures were observed under TEM and AFM microscopy studies, while irregular rod-like shape of NCC was observed under FESEM analysis. With 60 min hydrolysis time, XRD analysis demonstrated the highest NCC crystallinity degree with 79.5%. In thermal analysis by TGA and DSC, the shorter hydrolysis time tended to produce NCC with higher thermal stability. Thus, the isolated NCC from roselle-derived MCC has high potential to be used in application of pharmaceutical and biomedical fields for nanocomposite fabrication

Anhydride Production as an Additional Mechanism of Poly(3-hydroxybutyrate) Pyrolysis

Anhydrides production is newly proposed as an additional pyrolysis mechanism of a biopolymer, poly(3‐hydroxybutyrate) (PHB). In spite of many suggestions of multiple degradation mechanisms, simple random chain scission by β‐elimination has been accepted as an exclusive mechanism of the thermal degradation of PHB. However, a wide range of activation energy value of the degradation and the deviation from the random chain scission statistics have suggested the presence of other kinds of mechanism out of the random scission. To confirm other mechanisms out of the random scission, minor pyrolyzates from PHB were characterized with 1H/13C‐NMR, Fourier transform infrared spectroscopy, and fast atom bombardment mass spectrometry. As a result, crotonic anhydride and its oligomers were detected as minor products from condensation reactions between carboxyl groups. The anhydrides production must be one reaction out of the conforming process to the random degradation statistics and contribute to the complexity of PHB pyrolysis. An expected thermal degradation pathway of PHB was proposed

Multiple stage pretreatment affecting the properties of nanocellulose from oil palm frond

Cellulose extraction is an important step prior to nanocellulose production from lignocellulosic materials. The important view of present study rely on pretreatment method for cellulose extraction by comparing their effect on properties of nanocellulose. Oil palm frond was choose in focusing study as the potential value added product. Two pretreatment method were conduct which are multiple stage pretreatment and compared with single stage pretreatment. Peracetic acid was used as totally chlorine free (TCF) bleaching as it is environmental favorable. Multiple stage is the combination of physical, enzymatic and alkaline treatment while single stage represent for soda pulping process using 14% active alkaline charge in high temperature and pressure (160°C, 0.6-1.0 MPa). For multiple stage, superheated steam (300°C, 9 min) used as a prospective in open the fiber structure to allow the subsequent of enzymatic hydrolysis using xylanase. The xylanase was then access to catalyze 1, 4-beta-xylosidase which results in removal of hemicellulose and increase the cellulose content. In addition, xylanase enhanced the delignification process using alkaline treatment of 10% sodium hydroxide. Cellulose nanofibrillation was then conducted using a wet disc mill (WDM). Chemical analysis revealed the cellulose purity from multiple stage and single stage pretreatment with 83.4% and 94.6%. By characterization, the cellulose from multiple stage pretreatment results in high degree of polymerization up to 1,226, higher crystallinity (69.5%) and reach maximum thermal degradation at 326°C. The characteristics of cellulose eventually affected the nanocelluloses properties and by morphology, the nanocellulose produced from both treatment have the diameter size less than 100 nm

Multi-step pretreatment as an eco-efficient pretreatment method for the production of cellulose nanofiber from oil palm empty fruit bunch

Cellulose nanofiber (CNF) characteristics could be influenced by the pretreatment process during cellulose isolation, and generally pretreatment is conducted using harsh, less eco-efficiency chemical pretreatment. In this study, multi-step pretreatment method was evaluated for its eco-efficiency and compared with the conventional soda pulping method for cellulose isolation from oil palm empty fruit bunch (OPEFB). CNF developed from the celluloses pretreated by these methods were characterized. Some amount of hemicellulose residue left after the pretreatments whereby multi-step method showed higher amount of hemicellulose residue. This affected the diameter size of CNF obtained in which CNF from multi-step pretreated cellulose had smaller diameter range (13-33 nm) compared to that of soda pulping (18-52 nm). Crystallinity, thermal stability and degree of polymerization of the two CNFs are comparable. The superior characteristics of CNF obtained from multi-step pretreatment method, in addition to its eco-efficiency characteristic as evaluated based on the two key elements of eco-efficiency, namely, process re-engineering and by-products valorization, have recommended multi-step pretreatment method as a promising method for cellulose isolation from lignocellulose

Short bamboo fibers prepared by super-heated steam treatment for antistatic bio-composites

In order to apply short bamboo fiber (sBF) as a functional reinforcement of bio-composites having specific electrical properties, lignin-surfaced sBF was prepared via super-heated steam (SHS) treatment of bamboo. The sBF was easily isolated from the intrinsic fibrovascular bundle structure of bamboo after SHS treatment and pulverization. The isolated sBF was surfaced by brown-colored hydrophobic compounds, which were lignin-derived compounds generated during the SHS treatment. The functional bio-composites were prepared from the SHS-treated sBF and polypropylene and showed specific antistatic properties. Surface electrical resistance values of the composites decreased significantly with increase in the aspect ratio (AR) value of sBF. It is considered that the lignin-derived surfacing of sBF functions as an electron carrier in the composite. In particular, the longer sBF acts as an effective bridge for transporting electrons over long distances along conductive paths. From a cross-sectional microscopic image of the bio-composite, orientated sBFs were observed in its surface layer, supporting the suggestion of conductive path formation. Further, it was confirmed that the reinforcing effect of the presence of sBF was increased with increasing AR value