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Enzymatic Saccharification of Soda Pulp from Sago Starch Waste Using Sago Lignin-Based Amphipathic Derivatives

Abstract The aim of this research is to develop an enzymatic saccharification process of sago starch waste, with a small charge of cellulase. The waste contained a significant amount of residual starch, which was recovered as glucose by mild acid hydrolysis. The starch-free residue was subjected to soda-anthraquinone pulping to yield soda pulp and soda lignin. The lignin was converted to amphipathic lignin derivatives by the reaction with epoxylated polyethylene glycol analogues. The pulp was hydrolyzed with cellulase (Genencor GC220), with the amphipathic derivatives, to yield glucose. The lignin derivative-assisted, enzymatic saccharification was repeatedly conducted by reusing cellulase recovered by ultrafiltration from saccharification media. Saccharification efficiency with the derivatives was maintained at a high level even after the fourth run of saccharification, while the efficiency was remarkably decreased by repeated use of cellulase without additive. Thus, the amphipathic sago lignin derivatives enabled repeated use of cellulase for saccharification of sago starch waste.

PENYEMPURNAAN SIFAT PAPAN SERAT BERKERAPATAN TINGGI DARI CAMPURAN RUMPUT GELAGAH, TANDAN KOSONG KELAPA SAWIT, DAN BAMBU

Papan serat hardboard (HB) dari campuran Rumput Gelagah (RG), Tandan Kosong Kelapa Sawit (TKKS) dan bambu andong berpotensi untuk dikembangkan. Namun, percobaan pendahuluan menunjukkan HB tersebut tidak memenuhi persyaratan produk HB dari Japanese Industrial Standard (JIS) dan International Standard Organization (ISO). Tulisan ini mempelajari modifikasi pembuatan HB agar memenuhi standar produk tersebut. Modifikasi yang dilakukan meliputi penambahan konsentrasi alkali dalam pemasakan pulp dan merubah komposisi perekat. Hasil penelitian menunjukkan kualitas HB modifikasi meningkat dan mampu memenuhi persyaratan standar JIS dan ISO. Campuran serat pulp RG dan bambu andong/betung dimasak dengan konsentrasi alkali 10,5% dan 12% untuk serat dari TKKS. Campuran perekat yang digunakan adalah tannin-resorsinol-formaldehida (TRF), alum (tawas) dan emulsi lilin. Campuran serat yang paling banyak memenuhi standar adalah RG pulp (50%) + TKKS pulp (50%), diikuti RG pulp (100%), TKKS pulp (50%) + pulp bambu andong (50%), RG pulp (50%) + pulp bambu betung (50%). Serat yang masih kurang prospektif (bambu betung) diharapkan dapat diperbaiki melalui penggunaan perekat TRF dalam jumlah lebih banyak, arang aktif berukuran nano dan cross-linking agent .

KUALITAS PAPAN LAMINA DENGAN PEREKAT RESORSINOL DARI EKSTRAK LIMBAH KAYU MERBAU

Komponen kimia polifenol yang diekstrak dari kayu merbau (Intsia spp.) memiliki afinitas yang kuat terhadap resorsinol dan formaldehida dalam kondisi basa, membentuk suatu kopolimer yang dapat digunakan sebagai perekat. Tulisan ini menyajikan penggunaan perekat resorsinol dan ekstrak cair kayu merbau yang mengandung senyawa polifenol yang dikopolimerisasi dengan formaldehida sebagai perekat kayu lamina. Hasil penelitian menunjukkan bahwa kopolimerisasi ekstrak cair limbah kayu merbau menghasilkan resin berbobot molekul 49.658, yang dapat digunakan sebagai perekat dalam pembuatan papan lamina untuk lantai berupa 3 ply-1strip flooring parquet dengan 7 (tujuh) jenis kayu, yaitu: sungkai, karet, kempas, merbau, mangium, mahoni dan sengon. Kualitas perekatan dan sifat mekanik produk tersebut sebanding dengan produk sejenis berperekat impor serta tergolong tipe eksterior sangat rendah emisi formaldehida katagori E 0 atau F****.

KAJIAN STRUKTUR ARANG-PIROLISIS, ARANG-HIDRO DAN KARBON AKTIF DARI KAYU Acacia mangium Willd. MENGGUNAKAN DIFRAKSI SINAR-X

Kegunaan karbon aktif sangat luas dan penting untuk beragam aplikasi. Arang-hidro dari biomassa yang dibuat melalui proses karbonisasi hidrotermal merupakan prekursor alternatif terhadap prekursor konvensional untuk pembuatan karbon aktif yang selama ini banyak menggunakan arang dari proses pirolisis (prekursor konvensional). Tulisan ini menganalisa struktur kristalin arang-pirolisis dan arang-hidro suhu 200 ?C dan 300 ?C serta produk karbon aktif menggunakan difraksi sinar-X (XRD). Hasil penelitian menunjukkan bahwa indeks kematangan dan tingkat aromatisasi karbon dari prekursor (baik konvensional atau alternatif) meningkat setelah diaktivasi; jarak antar lapisan graphene (d002) semakin kecil, sementara itu derajat kristalinitas, jumlah, tinggi dan lebar lapisan aromatik semakin besar. Arang-hidro memiliki derajat kristalinitas, indeks kematangan dan tingkat aromatisasi lebih rendah dari arang pirolisis suhu 300?C dengan kandungan bahan mudah menguap lebih tinggi. Keduanya telah membentuk struktur karbon bersifat amorf. Karbon aktif dari arang-hidro suhu 300?C menghasilkan daya jerap iodin tertinggi. Analisis XRD terhadap arang-pirolisis dan arang-hidro suhu rendah dapat memprediksi porositas karbon aktif yang dihasilkan.

Crystallinity as a Non-Destructive Indicator of Wood Hardness at Standing Trees

Wood hardness is an important property for flooring, furniture products and structural utilization. Currently wood hardness can only be measured using destructive testing. As there is no suitable method for predicting wood hardness from standing trees, developing a non-destructive technique to predict wood hardness from plantations trees would provide significant benefits for evaluating optimal silvicultural treatments, and for selecting trees for tree improvement programs. It is proposed initillay that a possible non-destructive test may be developed using „crystallinity“ characteristics (degree of crystallinity (DC), crystalite width (CW) and length (CL) and microfibril angle (MFA)) determined using X-Ray diffraction. The aim of this study was to test the feasibility of using crystallinity as a non-destructive indicator of wood hardness. Experimentally, nine trees were taken representing small, medium and large diameter from five-year old fast growing teak plantation forest in Ciampea, Bogor, Indonesia. Wood hardness and crystallinity were determined following a standard testing regime. The results showed that MFA was negatively related to all hardness directions. Crstallite width only influenced side hardness with negative correlation, while degree of crystallinity only affected the end-grain hardness with positive correlation. Different vertical positions within tree only influenced the end-grain hardness value, while different radial positions had no effect on wood hardness. The optimum sampling height was found to be 80 cm, 130 cm, and 100 cm for radial, tangential and end-grain hardness, respectively. The relationship was based on the height that provided the highest correlation with the whole tree hardness values. Proposed models involving density and „crystallinity“ for predicting wood hardness are presented. While the R2 from the proposed models was mostly less than 0.50, however, the approach described provides a new way to predict wood hardness from 10 mm increment cores at standing trees.

Analysis of Wood’s Capacitance Characteristic to its Hardness

A capacitance sensor has been designed to investigate the correlation between wood capacitance value, Janka hardness rating and density. The sensor was developed based on parallel plates using copper as the electrodes. Capacitance values were measured using CV-circuit, 20 Vp-p, 2.5 MHz. Five wood specimens from forest plantation that is Karet (Hevea brasiliensis), Pulai (Alstonia sp.), Pinus (Pinus mercusii), Sengon (Paraserianthes falcataria), and fast growing teak (Tectona grandis) were tested. Each specimen was measured in tangential and radial directions under 0% moisture content conditions. The designed sensor was capable to distinguish the capacitance values in tangential and radial directions. The measurement results showed that wood capacitance value has a good relation with wood’s hardness and density.

STRUKTUR DAN KOMPONEN ARANG SERTA ARANG AKTIF TEMPURUNG KEMIRI

Activatied method of charcoal determines the specific usage of activated charcoal. Generally there recognize two activation methods to produce activated charcoal : physical and chemical methods. This research was carried out to identify structure and components of charcoal and activated charcoal from candlenut shell. Candlenut shell (Aleurites moluccana Willd) was carbonised in drum-kyln to produce charcoal, and then the product was activated in electrical retort by applying thermal activator with heating duration of 120 minutes at temperature of 550 C, 650 C and 750 C respectively. For further investigation, the heats at 750 C was chosed, combined with steam activator by heating duration of 90 minutes and 120 minutes. Fungsional group, crystallinity and porosity of candlenut shell, charcoal and activated charcoals sample test were characterized by Fourier Transform Infra Red FTIR X-Ray Difractometer XRD Scanning Electron Microscope SEM chemical compounds on sample test of candlenut shell, charcoal and activated charcoals Gas Chromatograph Mass Spectrometer Py-GCMS In turned out that activation process brought about changing in fungtional group pattern, increasing in crystallinity, pore opening and chemical compound reduction. The higher activation temperature caused the increase in crystallinity, pore diameter and chemical compound reduction. The activation by steam resulted activated charcoal with relatively cleaner pore. Structure, components, charcoal, activated charcoal, candlenut shell (Aleurites moluccana).

SIFAT PAPAN SERAT MDF DENGAN PENAMBAHAN ARANG

Charcoal with its porous structure enables it to adsorb pollutants in gaseous or liquid phase, although it does not perform as effectively as its corresponding active charcoal. Meanwhile, medium density fiberboard (MDF) has become one of the wood-based panels which develops rapidly. In relevant, this experiment dealt with charcoal addition during MDF type fiberboard manufacture bonded with urea formaldehyde adhesive and shaped under dry process, and the fiber materials for the MDF were the mixture of mangium and rubberwood TMP (Thermo-Mechanical Pulping) pulp at 3:1 proportion (w/w). Meanwhile, the fiber charcoal resulted from the carbonization of those mixed TMP pulp. Expectedly, the incorporation of charcoal could improve adsorption capacity of the resulting MDF. In this experiment, the amounts of charcoal as incorporated implied from the compositions of TMP fiber-charcoal mixture at consecutively 100:0 , 90:10, 80:20, and 70:30 based on oven dry weight. Observation was performed regarding MDF adsorption-capacities on benzene, chloroform, and formaldehyde