Optimasi Pembuatan Kertas Dari Serat Batang Padi dan Kertas Bekas

Kertas dikenal sebagai media utama untuk menulis mencetak, melukis dan masih banyak kegunaan lain yang dapat dilakukan dengan kertas Hal ini dapat menyebabkan berkurangnya kayu sebagai bahan baku utama pembuatan kertas padahal selain untuk pembuatan kertas, kayu juga digunakan untuk hal-hal lainnya. Penelitian ini dilakukan untuk menggali kemungkinan adanya potensi penggunaan bahan non kayu yaitu jerami padi untuk pembuatan kertas. Namun jika kertas hanya dibuat dari bahan jerami padi saja kurang memenuhi persyaratan dari segi kekuatan kertas disebabkan dari seratnya yang pendek. Untuk meningkatkan kekuatan serat perlu dicampur dengan serat kayu, misalnya dapat berasal serat kertas bekas selain itu perlu dilakukan penambahan zat aditif seperti tepung tapioka, frosin dan tawas. Penelitian ini bertujuan untuk mempelajari pengaruh variabel-variabel proses (suhu, konsentrasi NaOH. dan total padatan) terhadap kandungan selulosa dan kandungan lignin. Selain itu akan ditentukan kondisi optimum kekuatan kertas dengan penambahan bahan aditif pada konsentrasi tertentu. Dengan menggunakan metode regresi diperoleh model-model persamaan yang dapat menghubungkan pengaruh variabel-variabel proses seperti suhu. Konsentrasi dan total padatan terhadap kandungan selulosa dan kandungsn lignin dalam pulp yang dihasilkan. Sedangkan kondisi optimum kekuatan tarik kertas diperoleh pada penambahan zat aditif tepung tapioka 3% b/v sedangkan kondisi optimum ketahanan keras tehadap Fenyerapan air diperoleh pada penambahan campuran frosin dan tawas 5% v/v

Global Requirements of Chitosan for Medical and Food Applications

Chitosan is a biopolymer obtained by deacetylation of chitin which widely distribute in nature and biologically safe. This polymer exhibits several favor properties such as biodegradability, low toxicity and ability to form film hydrogel. Chitosan offers a wide range of unique application such as in medical application for hypocholesterolemic, antimicrobial and wound-healing properties, drug delivery and biologically active agent. For food application, chitosan is used for dietary ingredient, food preservative, edible film and coatings. The fulfill the requirement of medical and food application, it is necessary to prepare several tests, grouped in preliminary, confirmatory and other tests. The characterization of chitosan used for the application tests, viscosity and molecular weight determination. The main limitations in the use of chitosan in several applications are its high viscosity and low solubility at neutral pH. Low molecular weight (Mw) chitosans and oligomers can he prepared by degradation of chitosan such as chemical hydrolysis, oxidative degradation, irradiation of chitosan and enzymatic hydrolysis. For medical application, high degrees of deacetylation of chitosan is the important parameter of chitosan for medical and food applications. For some specific applications, these smaller molecules have been found to he much more usefu

Treatment of Paper Wastewater Using Combination of Coagulation Flocculation and Membrane Methods

The previous research has been conducted to find out the potential of non-wood fibers as an alternative for paper-making raw material. The non-wood fibers used are combination of rice straw and used paper. It was processed by using soda pulping method.The paper waste contains dissolved lignin component and other organic compounds in high pH condition can produce wastewater with high chemical oxygen demand(COD). In this research pulp or paper wastewater wast treated through combination of coagulation flocculation and membrane method to achieve a permitted level of COD. It was also determined the optimal condition which can reduce the COD value to fulfill the requirement for water disposal.The initial conditions of paper wastewatear are pH: 14, COD in the range of 3,000 - 11,000 ppm. The coagulation-flocculation process was conducted by using Poly Aluminium Chloride( PAC) as coagulant and anionic flocculant. The experiment is conducted by two steps. firstly determined the optimum coagulation flocculation (coagulant dose)for soluble organic material removal and then followed by micro-or ultrafiltration process. To produce asymmetric asymmetric membrane for filtration process. it was synthesized cellulose acetate membrane through phase inversion technique. The pore size of the membrane was modified by varying the composition of cellulose acetate in the range of 15-18 % w/w. The COD value of wastewater was analyzed before and after treatment to find out the effectivity of coagulation and the membrane process by studying its flux and rejection.The result showed that COD reduction less than 200 ppm can be reached through the treatment of combination of coagulation - flocculation and micro-or ultrafiltration process. The result also indicated that with initial COD 6,063 ppm. 10.000 ppm of coagulant, 1 ppm of flocculant and l8% w/w of cellulose acetate membrane. COD can be reduced up to 96.87

Uji Sterilitas dari Berbagai Jenis Pengemas yang Telah Dibuka Kemasan Sekundernya dan Disimpan Selama Tiga Hari

Sterile gauze is a health tool that is widely used in society. Sterile gauze used to cover wounds to prevent contamination. A box of sterile gauze that contains several sheets usually isn't necessary used up for one day. Therefore, sterility test has been done in this research. There were two types of sterile gauze,which were tested during the experiment. The types of primary packaging are made of parchment paper and plastic material. The research carried out for sterility test in different conditions i.e. the initial conditions and for three days storage after the secondary packaging was opened. Sterility testing using the medium tioglikolat and kasamino, which was sterilized by autoclave at 121'C for 15 minutes. As a positive control used Baccilus subtilis bacteria grown on medium tioglikolat, and the fungus candida albicans grown in medium kasamino. The result of the research showed that sterile gauze using parchment paper as primary packaging proved sterile. While the use of plastic primary packaging depending on the level of transparency. For the type of opaque white plastic packaging weren't proven to be sterile or have shown the growth of microorganisms. Unsterile gauze was count the number of colonies with ALT method and the results as much as as 1,6.10' CFU/ml

SYNTHESIS AND CHARACTERIZATION OF STARCH-CHITOSAN COMPOSITES

In this experiment, the composites based on chitosan-starch were synthesized at different weight ratios (3/7, 4/6, 5/5, 6/4, 7/3, 8/2, 9/1) by using 4 %v of glycerol as plasticizer. The influence of composition and the degree of deacetylation of chitosan on the properties of starch-chitosan composites film were studied. The films were observed on the aspect of mechanical characteristic, and % swelling, and biodegradability. Tensile strength of the composite films first increased and then decreased with chitosan addition. Otherwise, the addition of chitosan increased the elasticity of film and decreased % swelling. Films made of chitosan with the higher degree of deacetylation were found to have higher tensile strength and elongation in a tensile test

Kinetika Penurunan Kandungan Vitamin C Dalam Jus Jeruk Selama Penyimpanan

Kinetika hilangnya kandungan vitamin C dalam jus jeruk keprok (citrus reticulata) telah dipelajari dalam penelitian ini. Jeruk keprok dipilih sebagai bahan penelitian karena banyak dikonsumsi oleh masyarakat Jawa Timur. Jeruk ini dapat dikonsumsi langsung maupun dalam bentuk jus jeruk yang manis rasanya karena telah dicampur dengan air dan gula. Kandungan vitamin C dalam jus jeruk selama penyimpanan dipengaruhi antara lain: suhu penyimpanan, konsentrasi oksigen dalam jus selama penyimpanan, cahaya serta lamanya penyimpanan. Tahapan penelitian meliputi tahap pembuatan jus, tahap penyimpanan, tahap pengukuran kandungan vitamin C. Jus dibuat dari jeruk keprok segar dan disimpan pada tiga macam suhu ruang penyimpan yang berbeda yaitu: suhu ruang (29'C), suhu lemari es (13'C) dan suhu freezer (-5'C). Pengukuran kandungan vitamin C selama penyimpanan dilakukan dengan metode titrimetri dengan reagen iodin dan indikator amilum. Selain itu, pengaruh penambahan gula ke dalam jus jeruk juga dipelajari dalam penelitian ini. Kecepatan hilangnya vitamin C dalam jus jeruk keprok selama penyimpanan ditemukan mengikuti model kinetika reaksi order nol dengan energi aktivasi 14-15 kkal/mol

SINTESIS DAN OPTIMASI MEMBRAN SELULOSA ASETAT PADA PROSES MIKROFILTRASI BAKTERI

Tujuan dari penelitian ini adalah mensintesis membran selulosa asetat yang dapat dipakai untuk sterilisasi larutan media pertumbuhan bakteri. Dalam penelitian ini, diupayakan modifikasi ukuran pori membran yang sesuai untuk proses sterilisasi, yaitu mempunyai permeabilitas dan selektivitas tinggi terhadap bakteri tetapi rendah terhadap komponen media lain yang lolos melalui membran. Pembuatan membran dilakukan dengan sistem tiga komponen selulosa asetat, aseton, dan aditif formamida. Struktur pori membran diupayakan asimetris. Karakteristik membran dilakukan terhadap uji permselektivitas (rejeksi), permeabilitas (fluks), struktur dan morfologi membran.Uji dilakukan terhadap larutan umpan media tumbuh bakteri yang dikontaminasi dengan bakteri E-coli. Dari hasil penelitian diperoleh bahwa membran selulosa asetat dapat digunakan untuk menyaring bakteri. Komposisi larutan cetak berpengaruh pada nilai fluks dan nilai rejeksi.Makin tinggi komposisi larutan selulosa asetat, rejeksi makin tinggi dan fluks makin rendah. Proses gelasi (pemberian waktu untuk penguapan pelarut) dapat meningkatkan rejeksi dari 62,94% menjadi 67,83% pada waktu gelasi 1 menit. Kondisi terbaik dari percobaan komposisi selulosa asetat 16%, aseton 50% dan formamida 34%, waktu gelasi 1 menit dengan nilai rejeksi 67,83% dan nilai fluks 16,25 lt.m-2.jam-1. Pengamatan Scanning Electron Microscope (SEM) menunjukkan struktur pori membran asimetris

Zero Order Degradation Rate of Vitamin C in Fresh Orange and Strawberry Juices without Any Preservatives during Storage

Fresh orange and strawberry are rich in vitamin C, which is an essensial nutrient to promote a healthy imunne system. Vitamin C is easily degraded through oxidation process into dehydroascorbic acid during storage. Therefore, it is important to study the factors influencing the degradation rate of vitamin C in fruit juices without any preservatives. The aims of this research were to study the kinetic degradation of vitamin C in fresh orange (concentrated and nonconcentrated) and strawberry juices during storage and how the temperature affects these kinetics. Fresh juices were stored at room, refrigerated and frozen temperature. The content of vitamin C in fresh juices were analyzed using direct iodometric titration. Kinetic study of vitamin C degradation for these juices were carried out under isothermal condition. The degradation rates of vitamin C in fresh fruit juices based on zero kinetic model were compared. At room temperature the degradation rates of vitamin C in strawberry juice were about ten times faster than those in the orange juice. At refrigerated temperature the degradation rates of vitamin C in orange and strawberry juices with sugar were twice lower than theirs without sugar addition

The Effect of Plasticizer on mechanical Properties and Chemical Structure of Chitosan-Starch Film Composites

Plasticizer in and additive for plastic to improve its clasticity and flexibility. In this experiment, the composites based on chitosan-starch were synthesized at diferent wight ratio (7/3;8/2;9/1;10/0) by using 12.28 - 24.24% volume of glycerol of Plasticizer. This paper studies the influence of Plasticizer on mechanical and chemical properties of Chitosan-starch plastic film. The film were observed on the aspect of mechanical characteristic (tensile strength, elongation at break), and % swelling. The Mechanical characteristic of the film were characterized by autograph and swelling test. The alteration of chemical structure was studied by FTI

Pengaruh Hidrolisis Lanjut Terhadap Berat Molekul Chitosan

Chitosan adalah polisakarida linier yang tersusun dari ß-(1-4)-linked D-glucosamine dan N-acety-D-glucosamine yang tersebar secara acak. Secara umum chitosan dihasilkan dari produk deasetilasi chitin melalui proses reaksi kimia maupun reaksi enzimatis. Kualitas dan karakteristik chitosan sangat bervariasi tergantung dari metode dan proses pembuatannya