KOMPONEN KIMIA SEPULUH JENIS KAYU KURANG DIKENAL : KEMUNGKINAN PENGGUNAAN SEBAGAI BAHAN BAKU PEMBUATAN BIOETANOL

Abstract

Lesser known wood species refers to the woods already utilized much by the communities but confined only one or two of uses, generally as sawn timber and merchant wood. Consequently, diversification attempts are necessary to impart more added values to these species. One of the possibilities for such is their uses for bioethanol manufacture. In relevant, research was already performed to look into the possible utilization of 10 local lesser-known wood species, which comprised pangsor (Ficus callosa Willd.), jengkol (Pithecellobium rouslatum Kosterm.), petai (Parkia speciosa Hassk.), mami (Maesopsis eminii Engl.), balsa (Ochroma grandiflora Rowlee), ki cauk (Pisonia umbellifera (Forst) Seem.), buru manuk (Litsea monopeIata Pers.), kei renghas (Buchamania arborescens Blume), kei bonen (Crypteronia paniculata Blume ) dan ki hampelas (Ficus ampelas Burm.f.), as raw material for bioethanol. In assessing for bioethanol manufacture, it necessitates initially the data/ information on basic properties of each wood species, particularly the chemical composition, which was examined through the wood chemical analysis in accordance with the accepted standar, i.e. Norman Jenkin, Indonesian National Standart (SNI) and TAPPI. Analysis result on those 10 woods revealed that the cellulose content varied about 42,03-54,95%, lignin 22,66-35,20%, pentosan 15,36-17,15%, water content 3,95-10,99%, ash content 0,56-2,89%, silica content 0,12-0,84%. Solubility in cold water 1,29-5,55%, solubility in hot water from 4,41-11,19%, solubility in alcohol-benzene from 2,95-4,60% and solubility in NaOH 1% 10,35-22,89%. For bioethanol manufacture, it is desired that the woods base high values of consecutively cellulose and pentosan content, and solubility in NaOH 1%; and concurrently have low content lignin, ash and silica, low solubilities in cold water, hot water and alcohol benzene. Judging from those criteria and aided by the statistics interpretation, it indicates that 8 out of 10 species were technically prospective as raw material for bioethanol, i.e. from most until the least being kei rengas, mami, petai, jering, balsa, ki hampelas, ki cauk, and burumanuk, respectively. Meanwhile, kei bonen and pangsor are regarded as unsuitable for bioethanol.