Proizvodnja bioetanola na blago kiselinskim hidrolizatima pšenične slame dobivenim pomoću sumporne kiseline u različitim mjerilima

master's thesis

• Title (english): Production of bioethanol on the mild acid wheat straw hydrolysates obtained by sulfuric acid in various scales
• Author: Marina Grubišić
• Mentor: Božidar Šantek (mentor)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Biochemical Engineering); (Laboratory for Biochemical Engineering, Industrial Microbiology and Malting and Brewing Technology); Zagreb
• Defense date and country: 2017-09-26, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Biotechnology

Abstract

Kako bi se ispitao utjecaj temperature na uspješnost procesa predobrade pšenične slame s 0,5 % sumpornom kiselinom u visokotlačnom reaktoru, procesi predobrade provedeni su na temperaturama od 150 oC, 160 oC, 170 oC, 180 oC, 190 oC i 200 oC uz konstantno vrijeme zadržavanja (tz) od 5 minuta. Najviša koncentracija ksiloze (13,0154 g L-1) ostvarena je pri temperaturi od 160 oC, a glukoze (4,7257 g L-1) na temperaturi od 200 oC. Kako bi se ispitao učinak vremena zadržavanja na uspješnost procesa, primjenjena su vremena zadržavanja od 1 i 10 minuta na tri temperature: 160, 180 i 200 oC. Najveći maseni udio glukana uočen je predobradom na 200 oC i tz = 10 min i iznosi 30,42 %, a ksilana na temperaturi od 160 oC i tz =5 min i iznosi 68,64 %. Analizom sastava hidrolizata odabrano je 5 različitih hidrolizata za usporedbu rasta i proizvodnje etanola u Erlenmeyer tikvicama pomoću dva soja kvasca S. cerevisiae: (1) divlji soj i soj Y9. Najveća uspješnost procesa proizvodnje etanola zabilježena je kod uzgoja soja Y9 na hidrolizatu dobivenom predobradom na temperaturi od 180 oC i vremenu zadržavanja od 10 minuta pri čemu je ostvarena produktivnost od 0,045 g L-1 h-1 i efikasnost od 43,25 %. Na istom hidrolizatu proveden je uzgoj kvasca soj Y9 i u poluindustrijskom mjerilu tj. horizontalnom rotirajućem cijevnom bioreaktoru pri čemu je dobivena produktivnost od 0,143 g L-1 h-1 i efikasnost od 64,01 %.

Abstract (english)

In order to investigate the effect of temperature on the efficancy of wheat straw pretretmant with 0,5 % sulfuric acid in high-pressure reactor, processes were conducted on different temperatures: 150 oC, 160 oC, 170 oC, 180 oC, 190 oC and 200 oC, with a constant residence time of 5 minutes. The highest xylose concentration (13,0154 g L-1) was achieved in pretretmant carried out at temperature of 160 oC and the highest glucose concentration (4,7257 g L-1) at temperature of 200 oC respectively. To investigate the effect of residence time on the efficancy of procces, residance time of 1 and 10 minutes were were also used at three temperatures: 160, 180 and 200 oC. The highest mass fraction of xylan (68,64 %) was achieved at temperature of 160 oC and residence time of 5 minutes. The highest mass fraction of glucan was 30,42 %, and it was observed at temperature of 200 oC and residence time of 10 minutes. Based on the composition of acid hydrolysates of wheat straw, five hydrolysates were selected for further research with two strains of S. cerevisiae: wild-type and type Y9. The most successful ethanol production process was observed by yeast strain Y9 on the broth containing wheat straw hydrolysates obtained during pretretmant at 180 oC and residence time of 10 minutes. In this bioprocess productivity of 0,045 g L-1 h-1 together with efficiency of 43,25 % were observed. During anaerobic cultivation of S. cerevisiae strain Y9 in the horizontal rotating tubular bioreactor on the same hydrolysate bioprocess productivity reached value of 0,143 g L-1 and efficiency of 64,01 % respectively.

• Keywords: etanol; pšenična slama; kiselinska predobrada; Saccharomyces cerevisiae; različita mjerila
• Keywords (english): ethanol; wheat straw; acid pretreatment; Saccharomyces cerevisiae; different scales
• Language: croatian
• URN:NBN: urn:nbn:hr:159:959653
• Study programme: Title: Bioprocess Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva (magistar/magistra inženjer/inženjerka bioprocesnog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2017-11-09 10:58:55