The Effectiveness of Physical and Alkali Hydrothermal Pretreatment in Improving Enzyme Susceptibility of Sweet Sorghum Bagasse

Sweet sorghum bagasse (SSB) obtained after juice extraction is a potential feedstock for fermentable sugars production that can be further fermented to different kinds of products, such as ethanol or lactic acid. The proper particle size resulted from phsyical pretreatment and different pretreatment processes including water, alkali, hydrothermal, and alkali hydrothermal for improving enzyme susceptibility of SSB have been investigated. After grinding to particle sizes of 420 ?m the sweet sorghum bagasse was washed to eliminate residual soluble sugars present in the bagasse. Dosages of cellulase enzyme used in saccharification were 60 and 100 FPU/g substrate, respectively. The results showed that SSB with particle sizes of 250-420 ?m had the highest cellulose (38.33%) and hemicellulose content (31.80%). Although the yield of reducing sugar of 250-420 ?m size particles was lower than that of smaller particle (<250 ?m), the former was more economical in the energy consumption for milling process. The yields of reducing sugar obtained from enzymatic hydrolysis of alkali hydrothermal pretreated sweet sorghum bagasse were 1.5 and 0.5 times higher than that from untreated sweet sorghum bagasse at enzyme loading of 100 and 60 FPU/g substrate, respectively. Furthermore, alkali hydrothermal pretreatment was able to remove as much as 85% of lignin. Morphological analysis using SEM (Scanning Electron Microscope) showed that samples treated with alkali hydrothermal have more pores and distorted bundles than that of untreated sweet sorghum bagasse. Meanwhile, XRD (X-ray diffraction) analysis showed that pretreated samples had a higher crystallinity and smaller crystallite size than untreated sweet sorghum bagasse, which might be due to removal of amorphous lignin components

Central Kalimantan's Fast Growing Species: Suitability for Pulp and Paper

Recent studies of fast growing species grown in PT. Sari Bumi Kusuma, Central Kalimantan, show that based on their fiber dimensions there are five species, namely Endospermum diadenum, Dillenia spp., Adinandra dumosa, Adiandra sp., and Nauclea junghuhnii with good potential for pulp and paper production. The fiber length of those five wood species are was more than 2,200 µm on average. This paper studies the physical properties, fiber dimensions and their chemical contents to predict the paper and pulp quality. The result shows that all of the species were classified in the medium to high density category. All species were classified into the first class quality for pulp and paper. Based on chemical contents, Dillenia sp. is the most suitable species due to its high value of holocellulose and a-cellulose, low lignin content, and its fiber length is about 3,119 µm on average. A. dumosa also has good opportunities because it had the longest fiber lengths (3,137 µm on average) and high value of holocellulose, even though it has the highest lignin content. While Nuclea junghuhnii is less suitable due to low values of holocellulose and a-cellulose

Biological Pretreatment of Oil Palm Frond Fiber Using White-Rot Fungi for Enzymatic Saccharification

Oil palm frond is one type of lignocellulosic biomass abundantly and daily available in Indonesia. It contains cellulose which can be converted to glucose, and further processed to produce different kinds of value &ndash;added products. The aim of this research is to study the effects of biological pretreatment of oil palm frond (OPF) fiber using Phanerochaete chrysosporium and Trametes versicolor on the enzymatic saccharification of the biomass. The OPF fiber (40-60 mesh sizes) was inoculated with cultures of the two fungi and incubated at 27 &deg;C for 4 weeks. The samples were taken after 1, 2, 3, and 4 weeks of incubation. Chemical components of the biomass after pretreatment were analyzed. The saccharification of the pretreated samples using cellulase and &beta;-glucosidase was performed in a water bath shaker at 50 &deg;C for 48 hours. The concentration of reducing sugar increased with increasing of incubation time, either in those pretreated with culture of P. chrysosporium or with T. versicolor. Pretreatment of OPF fiber using single culture of T. versicolor for 4 weeks gave the highest reducing sugar yield (12.61% of dry biomass)

Microwave-assisted hydrothermal treatments for biomass valorisation : a critical review

The sustainable conversion of biomass into biofuels, chemicals and biomaterials has gained increasing attention to ensure the well-being of present and future generations. Among the different technologies available to date for the valorisation of biomass, microwave-assisted hydrothermal conversion has recently appeared as a state-of-the-art technology, capable of furnishing a wide range of reaction products for the energy, pharmaceutical and chemistry sectors. This emerging technology combines the inherent benefits of microwave heating and the sustainable features of biomass hydrothermal valorisation. Herein, for the first time, this critical review summarises and analyses all the work conducted to date on the use of microwave-assisted hydrothermal processes (including microwave-assisted carbonisation, liquefaction and treatment/hydrolysis) for the conversion of biomass into hydrochar, bio-crude (bio-oil) and valuable chemicals. In particular, this work has put together vital information addressing the influences of the reaction conditions (temperature, time, amount and type of catalyst, biomass loading and type, and microwave power) on the yields and key properties of the reaction products. The relationships between these processing parameters and the chemical transformations involved in the processes (hydrolysis, dehydration, decarboxylation, condensation and re-polymerisation) have been described in detail, and reliable comparisons have also been established between microwave-assisted and conventional hydrothermal technologies when data were available. As a result, this critical review collects essential information on the use of this cutting-edge, recently appeared microwave-assisted hydrothermal technology, and paves the way for its expansion and future development and commercialisation

Campuran Lateks Karet Alam-Stirena dan Poliisosianat sebagai Perekat Kayu Lamina Blends Of Natural Rubber Latex-Styrene And Polyisocyanate For Laminated Wood Adhesive

Each adhesive has its own strengths and weaknesses due to its bond strength, or its resistance to stress, heat, moisture and organisms. Blending of several adhesives could combine properties of each. Besides, it might reduce adhesives prices as well. In this research Natural Rubber Latex-Styrene (NRL-St) was blended with Polyisocyanate (PI) or API (Aqueous Polymer Isocyanate) adhesive. The aim of this research was to study the effects of compositions of adhesive blends on adhesive properties, and the effects of composition of adhesive blends and pressing time on bond strength of laminated wood (Acacia mangium). Blending compositions of NRL-St/PI were 100/0, 80/20, 60/40, 50/50, 40/60, 20/80, and 0/100. Physico-chemical properties of these blends of adhesives, including solid content, pH, viscosity and mixtures homogenity were analyzed. Blends of NRL-St with PI adhesive had total solid contents range from 42.39 to 50.58%, pH from 7.45 to 7.98, and viscosity from 3506 to 5661 cp. Results of this study showed that optimum composition of blends of NRL-St and API adhesives for producing laminated wood of Acacia mangium was 50/50 (w/w). At this composition the shear strength of laminated wood was 7.06 MPa, while delamination ratio in cold and boiling water were 0% and 4.89% respectively. These values could meet Japan Agriculture Standard (JAS) for laminated wood (shear strength > 5.4 MPa and delamination ratio < 10%). Optimum pressing time for producing laminated wood using API adhesive as well as blends of NRL-St/API (50/50) was two hours