Concentrated Acid Hydrolysis Process The Arkanol process works by adding 70-77% sulphuric acid to the biomass that has been dried to a 10% moisture content. The acid is added in the ratio of 1.25 acid to 1 biomass and the temperature is controlled to 50C. Water is then added to dilute the acid to 20-30% and the mixture is again heated to 100C for 1 hour. The gel produced from this mixture is then pressed to release an acid sugar mixture and a chromatographic column is used to separate the acid and sugar mixture.
Dilute Acid Hydrolysis The dilute acid hydrolysis process is one of the oldest, simplest and most efficient methods of producing ethanol from biomass. Dilute acid is used to hydrolyse the biomass to sucrose. The first stage uses 0.7% sulphuric acid at 190C to hydrolyse the hemi cellulose present in the biomass. The second stage is optimised to yield the more resistant cellulose fraction. This is achieved by using 0.4% sulphuric acid at 215C.The liquid hydrolates are then neutralised and recovered from the process.
Sugar Fermentation Process The hydrolysis process breaks down the cellulostic part of the biomass or corn into sugar solutions that can then be fermented into ethanol. Yeast is added to the solution, which is then heated. The yeast contains an enzyme called invertase, which acts as a catalyst and helps to convert the sucrose sugars into glucose and fructose (both C6H12O6). The chemical reaction is shown below: C12H22011+H2O----->C6H12O6+C6H12O6
sucrose glucose fructose
The fructose and glucose sugars then react with another enzyme called zymase, which is also contained in the yeast to produce ethanol and carbon dioxide. The chemical reaction is shown below: C6H12O6----->2C2H5OH+2CO2
glucose/fructose ethanol
The fermentation process takes around three days to complete and is carried out at a temperature of between 250C and 300C.
เห็นเป็นภาษาอังกฤษก็อย่าเพิ่งตกใจ ส่วนใหญ่อธิบายแค่กระบวนการและวิธีการเปลี่ยน cellulose เป็น ethanol
note 2 กระบวนการแรกเป็นการเปลี่ยน biomass(cellulose hemicellulose lignin) ให้เป็นน้ำตาล เลือกเอาวิธีไหนก็ได้ ส่วนอันสุกท้ายเป็นการเปลี่ยนน้ำตาลเป็น ethanol
ยังไงก็จะลองหาที่เป็น thai มาให้นะ แต่ถ้าจะเอาละเอียดแบบนี้ส่วนใหญ่คงมีแต่ภาษาอังกฤษ
follow this link for more information:http://www.esru.strath.ac.uk/EandE/Web_sites/02-03/biofuels/what_bioethanol.htm
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