Effects of Pretreatments of Napier Grass with Deionized Water, Sulfuric Acid and Sodium Hydroxide on Pyrolysis Oil Characteristics

Abstract

The depletion of fossil fuel reserves has led to increasing interest in liquid bio-fuel from renewable biomass. Biomass is a complex organic material consisting of different degrees of cellulose, hemicellulose, lignin, extractives and minerals. Some of the mineral elements tend to retard conversions, yield and selectivity during pyrolysis processing. This study is focused on the extraction of mineral retardants from Napier grass using deionized water, dilute sodium hydroxide and sulfuric acid and subsequent pyrolysis in a fixed bed reactor. The raw biomass was characterized before and after each pretreatment following standard procedure. Pyrolysis study was conducted in a fixed bed reactor at 600 o C, 30 o C/min and 30ml/min N 2 flow. Pyrolysis oil (bio-oil) collected was analyzed using standard analytic techniques. The bio-oil yield and characteristics from each pretreated sample were compared with oil from the non-pretreated sample. Bio-oil yield from the raw sample was 32.06 wt% compared to 38.71, 33.28 and 29.27wt% oil yield recorded from the sample pretreated with sulfuric acid, deionized water and sodium hydroxide respectively. GC-MS analysis of the oil samples revealed that the oil from all Page 2 of 38 the pretreated biomass had more value added chemicals and less ketones and aldehydes. Pretreatment with neutral solvent generated valuable leachate, showed significant impact on the ash extraction, pyrolysis oil yield, and its composition and therefore can be regarded as more appropriate for thermochemical conversion of Napier grass.

Valorization of Napier grass via intermediate pyrolysis: Optimization using response surface methodology and pyrolysis products characterization

“…From the reactor size and carrier gas flowrate reported by the authors, vapor residence was around 1.425 min (85 sec), which is long enough to result to severe secondary cracking of the pyrolysis vapor at such a high temperature. Some classical studies on the pyrolysis of Napier grass have also been reported by our research group recently (Mohammed et al, 2015b;Lim et al, 2015, Mohammed et al, 2016a, 2016b, 2016d, Lim et al, 2016. To date, no study on pyrolysis of Napier grass is available in the literature that deals with collective examination of pyrolysis temperature, heating rate, inert gas flowrate on the products distribution and composition.…”

“…Lignocellulosic biomass such as forest residues, agro-wastes, energy grasses, aquatic plants, algae, continues to again attention as a suitable alternative energy source. They are non-food materials and consist carbon, which can be converted into high-grade fuel or fuel precursor, biochemicals and other valuable product (Mohammed et al, 2016a;2016b). However, biofuel from these materials is generating another concern.…”

Co-pyrolysis of Rice Husk with Underutilized Biomass Species: A Sustainable Route for Production of Precursors for Fuels and Valuable Chemicals

“…The reaction time was kept at 60 min (±2 min) after the reaction temperature reaches 600°C. Bio-oil, bio-char and non-condensable yields were determined according to equations 1, 2 and 3 respectively [34]. Bio-oil collected was characterized.…”

Markedly Different Decomposition Temperature and Products of Biomass Pyrolysis at Low Temperature—Differentiation of Acids in Their Effects on Pretreatment

“…Commonly used techniques include acid treatment [13][14][15][16], alkali treatment [14,17], steam explosion [18], hot-water extraction [19,20], etc. Acid pretreatment as a chemical method is effective in removing minerals from lignocellulosic biomass and can significantly increase the bio-oil yield in thermal pyrolysis [17,21,22]. Previous studies also demonstrated that the removal or passivation of minerals in biomass by mineral acid is an effective method for improving the yields for anhydrosugars from the pyrolysis of biomass [21,23].…”