Effects of Several Synthesis Conditions on Bond Strength of Plywood Adhered with Natural Rubber Latex – Styrene Adhesive

This report discusses the effects of synthesis conditions on bond strength of plywood adhered with natural rubber latex - styrene adhesive. Synthesis variables observed were catalyst (with and without catalyst), pre-stirring (0 and 3 hours) and heating time (1 and 2 hours). Three-ply plywood samples were prepared from Albizia (Paraserianthes falcataria) and Red meranti (Shorea, sp.) veneers and their gluability were evaluated in accordance to Indonesian Standard (SNI 01-2704-1992). The results revealed that synthesis conditions (i.e. catalyst, pre-stirring and heating time) did not significantly influence the bond strength of plywood. Natural rubber latex – styrene adhesive is very appropriate as adhesive for Red meranti plywood. Nevertheless, it can be used as limited interior application for Albizia plywood. An addition of 10% phenol formaldehyde (PF) in natural rubber latex - styrene adhesive slightly improved the exterior type bond strength of Red meranti plywoo

Effect of Corn Steep Liquor on Bamboo Biochemical Pulping Using Phanerochaete Chrysosporium

The effect of corn steep liquor (CSL) loading on white rot fungi inoculums in the biochemical pulping of betung bamboo was investigated. The best condition of the pretreatment was also determined. There were two conditions of CSL amount used i.e. 1% (v/w) and 10 % (v/w) of CSL used in 100 ml of inoculums. In short, fresh bamboo chips without bark was incubated with Phanaerochaete chrysosporium inoculum stocks for 30 and 45 days at room temperature and followed by Kraft and Soda pulpings. SEM images of pretreated chips were taken after incubation. The pulp yield, Kappa number, freeness, delignification selectivity, and brightness were analyzed. The more CSL amount added with Kraft process gave better results on pulp yield. Increasing incubation time increased pulp yields and decreased the Kappa numbers. On the other hand, freeness and brightness of pulp increased especially for Kraft process. The SEM images showed that there were cell walls degradation activities. The best properties of pulp were obtained by the Kraft process for the treatment of 10% CSL with 30 days of incubation time

The Effect Of Adsorbent Agents: Silica, Andisol, Leca, Anthracite, And Activated Carbon On Pollutant Uptake In The Citarum River (Pengaruh Agen Penjerap Silika, Andisol, Leca, Antrasit, dan Karbon Aktif terhadap Penjerapan Polutan di Sungai Citarum)

Sungai Citarum merupakan sungai terpanjang dan terbesar di Jawa Barat, Indonesia yang mempunyai fungsi vital sebagai sumber air. Pengolahan air sungai Citarum sebelum disalurkan ke masyarakat diperlukan untuk menghilangkan pengotor karena kandunganpengotor pada air sungai Citarum melebihi batas ambang yang dipersyaratkan untuk air konsumsi. Saat ini proses penjerapan atau adsorpsi merupakan proses yang umum digunakan pada Perusahaan pegolahan air karena efektifitasnya. Pada penelitian ini, efektifitas lima agen penjerap yaitu silika, andisol, hidroton, antrasit, karbon aktif teladievaluasi dengan perbedaan rasio padatan dan larutan, dan waktu kontak. Setelapengolahan, kekeruhan dan logam berat dalam air dianalisa. Karakteristik permukaan, gugus fungsi, dan luas permukaan dari kelima agen penjerap dianalisa masing-masing menggunakan FE-SEM (Field Emission - Scanning Electron Microscopes), FTIR (FourieTransform Infrared Spectroscopy), dan analisa luas permukaan BET (Brunauer-EmmettTeller). Hasil analisa menunjukan bahwa masing-masing andisol dan LECA menurunkankekeruhan dari air Citarum dari 21.30 NTU (Nephelometric Turbidity Unit) menjadi 1.23 da2.52 NTU setelah waktu kontak 10 menit. Karbon aktif membutuhkan waktu 10 menit lebih lama untuk menurunkan kekeruhan menjadi 2.26 NTU akan tetapi karbon aktif memiliki luas permukaan yang paling tinggi yaitu 548.31 (m2/g). Luas permukaan berkaitan dengan hasil FE-SEM dimana karbon aktif memiliki pori yang teratur dan berukuran besar. Padaumumnya, andisol, LECA, dan karbon aktif telah berhasil menurunkan kekeruhan air Sungai Citarum yang berkaitan dengan luas permukaan partikelnya

Kraft and Soda Pulping of White Rot Pretreated Betung Bamboo

This research was conducted to study the effects of pre-treatment with white-rot fungi on pulp properties of betung bamboo. Inoculum stocks of white-rot fungi (25 ml) were injected into polybags contained barkless fresh bamboo chips. Each polybag contained 214.9–286.8 g oven dry weight of chips. Bamboo chips in the polybags were inoculated by Pleurotus ostreatus and Trametes versicolor. Both of them were then incubated for 30 and 45 days at room temperature. Bamboo chips were cooked using soda and Kraft processes. The cooked bamboo chips were then defiberize using disc refiner for 3 times. Pulp yield, kappa number and degree of freeness of the pulp were then analyzed. The treatment of two white rot fungi, gave different effects on the characteristic of betung bamboo pulp. The effects of fungi treatment on kappa number and degree of freeness can be seen only at samples cooked using kraft process. Incubation time did not affect pulp yield of bamboo treated with both fungi, but it affected kappa number and degree of freeness of bamboo pulp cooked using kraft process. Bamboo treated with T. versicolor incubated for 45 days and cooked using kraft process produced the best pulp quality with high pulp yield