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 attemps are necessary to impart more added values to those 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 jengkol petai (), manii (), balsa (), ki cauk ((Forst) Seem.), huru manuk (), ki renghas (Buchanania), ki bonen () dan ki hampelas (), 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 have high values of consecutively cellulose content, pentosan content, and solubility in NaOH 1%; and concurrently have low content lignin, ash and silica, low sollubilities 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 ki rengas, manii, petai, jering, balsa, ki hampelas, ki cauk, and hurumanuk, respectively. Meanwhile, ki bonen and pangsor are regarded as unsuitable for bioethanol.