Study On Microwave Pyrolysis Of Sapindus And Its Products

Energy is the foundation of economic and social development. As the exhaustion of fossil energy, the discovery of noval renewable energy become challenging around the world. Biomass energy, which is a renewable energy, is expected to be one of the main energy replaced for traditional fossil energy in the future. Hence, the development of biomass energy is becoming more and more significant. With Sapindus as raw material, this study break through the problem of stiff testa. The bio-oil and activated carbon was made through rapid microwave pyrolysis, providing a new approach to fully use Sapindus as a novel renewable energy.First, this study analysed the element and component composition of Sapindus. The mass change rule has been researched via thermogravimetric analysis, providing a theoretical reference for the technological selection of Sapindus microwave pyrolysis.The systematic research of Sapindus microwave pyrolysis was proceeded by single factor experiments with microwave power, pyrolysis temperature, pyrolysis time and addition amount of absorbent as main factors, then the optimal technological parameters has been confirmed. The Box-Behnken response surface method was used for optimization of bio-oil production. The best technological combination was 600.80℃ pyrolysis temperature,1.93 kW microwave power,1.87% addition amount of absorbent and 7.43min pyrolysis time with 47.67% bio-oil yield.Besides, based on this technological optimization of Sapindus bio-oid production, the physico-chemical analysis show that the highest acid value and strong corrosivity would be achieved when the moisture of bio-oil is 53.48%. The GC-MS analysis of volatile components show a complicated composition of bio-oid, highest oleic acid content with 18.71% relative peak area of total volatile components and 30.25% relative peak area of fatty acids. To obtain the simple-composition bio-oil, the effect of catalyzers HC1, H2SO4, H3PO4, KOH, NaOH, CaO, MgO, MgCl2 and CaCl2 on the bio-oil composition and H2, CO, CH4 of flammable gas were studied. The results suggest that the pretreatment with grinding and inorganic acid to Sapindus was effective for the breakdown of fatty acid ester bond. It will enormously increase fatty aicd content with more than 80% relative peak area while little affect the composition of H2, CO and CH4. The addition of MgCl2 would up-regulate the relative content of phenol and aromatic compounds and elevate H2 and CH4 relative content of flammable gas. Furthermore, the supplement of KOH and NaOH can promote the breakdown of long chain fatty acid into alkane and olefin substances.Finally, the activated carbon was made from coke of the microwave pyrolysis of Sapindus. With iodine adsorption value as the main index and KOH as activator, the technological optimization was performed with orthogonal test. Then, the optimized activated carbon got through infrared spectroscopic analysis and field emission scanning electron microsopy. The results indicate that the preferable adsorbability of activated carbon with iodine adsorption vale 1036 mg/g meet the first-class national standard for drinking water.