Mohammed O. Abdulsattar

I am a PhD student in the Chemical Engineering department at University of Hull, UK. Lignocellulose conversion to biofuel is my research area. Currently I am using wheat straw as the raw material and convert it to bio-ethanol. The conversion of WS to bio-ethanol include four steps; pre-treatment, enzymatic hydrolysis, fermentation and distillation. The pre-treatment process is the most important step due to high energy use and formation of inhibitors. There are different types of pre-treatments; Biological, Physical, Chemical and Physico-chemical. My research in university of Hull focus on the physical and chemical pre-treatment of the WS. The applying process to the BRISK funding was simple and straightforward, after I checked the Rigs list I found that ENEA would be the best facility with the equipment that I want to use and their research coincides with my research interests. I contacted Dr. Francesco Zimbardi to set the working plan and the time frame for visiting, he filled me with all the information regarding the equipment, he also advise me on the best time visit and how to get the most of my visit.  

We have conducted two set of experiments; the first set with Liquid hot water treatment (without and with H2SO4, 3%) by using high pressure and temperature reactor. The WS was treated as slurry (5 % w/w solid to liquid ratio) at 210°C for 30 min; the same conditions were used for C-LHW but at lower temperature, i.e. 164 °C. 

The second set with Steam Explosion (without and with H2SO4, 3%). Both the SE experiments without acid and with acid (H2SO4, 3%) were performed by using 500 g of WS (DM) and at 224 °C and 200 °C for 10 min and 5 min respectively.  

All the samples from LHW treatment with and without acid as well as SE with and without acid were filtered. The liquid fraction was tested for hemicellulose content and sugar monosaccharides. The solid fraction was subjected to enzymatic hydrolysis by using Cellic Ctec2 enzymes for 72 h at 50°C and 150 r.p.m in the incubator shaker. At the end of the hydrolysis the remaining solid weight was recorded and the liquid fraction was tested for sugar monosaccharides. High Performance Liquid Chromatography (HPLC) was used to determine the monosaccharides sugars produced after the enzymatic hydrolysis to compare and evaluate the pre-treatment process efficiency.  

Furthermore, the raw WS was tested using the NLRA stander protocol. In summary, the dray WS was hydrolysed in two steps; the first hydrolysis was carried by treating 300 mg of dry WS with 3 ml of 72% H2SO4 at 30 °C or 1 h. In the second hydrolysis, 84 ml of deionized water was added to the samples, then the samples were autoclave at 121 °C for 1h. The samples were filtered, the liquid fraction was used to determine the cellulose, hemicellulose with the (HPLC) and soluble lignin with UV-spectrophotometer. As for the solid fraction, it was used to test the insoluble lignin and ash. The WS composition is 40 % cellulose, 33% hemicellulose, 18% lignin and 9 % ash.   

The results shows that by using 3% H2SO4 instead of just water, the lignin removal was increased in both SE and LHW treatment and therefore the reduced sugars from enzymatic hydrolysis was increased. All the analysis and enzymatic hydrolysis were carried in duplicate and the average results were used.  

The BRISK initiative benefit me not only scientifically, but also personally by exchanging knowledge and experience with other researchers. I would like to thank everyone in ENEA team, my supervisor Dr. Sharif H. Zein for all his sport and the Higher Committee for Education Development in Iraq (HCED-Iraq) for fully sponsor my PhD study in the UK.