来自微藻的第三代生物燃料正成为可持续能源的必要条件。在这种情况下,本研究探索了在废水中生长的微藻生物质的水热液化(HTL),由30%的普通小球藻组成,69%斜方,和1%的蓝细菌,以及随后生产的生物油的升级。这项工作的新颖之处在于将废水中的微藻培养与HTL结合在生物精炼方法中,使用催化剂来升级生物油。测试了不同的温度(300、325和350°C)和反应时间(15、30和45分钟)。在375°C下用钴-钼(CoMo)催化剂进行1小时的生物油改质。后HTL,尽管氢与碳(H/C)比从1.70降至1.38-1.60,但氧与碳(O/C)比也从0.39降至0.079-0.104,较高的热值从20.6增加到36.4-38.3MJkg-1。棕榈酸是所有生物油样品中的主要成分。最高的生物油产率是在300°C下30分钟(23.4%)。升级增加的长链烃,如十七烷(5%),表明生物燃料潜力,尽管含氮化合物如十六烯腈表明需要进一步加氢脱氮。水相,固体残留物,和来自HTL的气体可用于生物质栽培等应用,生物氢,有价值的化学品,以及碳复合材料和水泥添加剂等材料,推动循环经济。该研究强调了微藻衍生的生物油作为可持续生物燃料的潜力,尽管需要进一步改进以满足当前的燃料标准。
Third-generation biofuels from microalgae are becoming necessary for sustainable energy. In this context, this study explores the hydrothermal liquefaction (HTL) of microalgae biomass grown in wastewater, consisting of 30% Chlorella vulgaris, 69% Tetradesmus obliquus, and 1% cyanobacteria Limnothrix planctonica, and the subsequent upgrading of the produced bio-oil. The novelty of the work lies in integrating microalgae cultivation in wastewater with HTL in a biorefinery approach, enhanced using a catalyst to upgrade the bio-oil. Different temperatures (300, 325, and 350 °C) and reaction times (15, 30, and 45 min) were tested. The bio-oil upgrading occurred with a Cobalt-Molybdenum (CoMo) catalyst for 1 h at 375 °C. Post-HTL, although the hydrogen-to-carbon (H/C) ratio decreased from 1.70 to 1.38-1.60, the oxygen-to-carbon (O/C) ratio also decreased from 0.39 to 0.079-0.104, and the higher heating value increased from 20.6 to 36.4-38.3 MJ kg-1. Palmitic acid was the main component in all bio-oil samples. The highest bio-oil yield was at 300 °C for 30 min (23.4%). Upgrading increased long-chain hydrocarbons like heptadecane (5%), indicating biofuel potential, though nitrogenous compounds such as hexadecanenitrile suggest a need for further hydrodenitrogenation. Aqueous phase, solid residues, and gas from HTL can be used for applications such as biomass cultivation, bio-hydrogen, valuable chemicals, and materials like carbon composites and cement additives, promoting a circular economy. The study underscores the potential of microalgae-derived bio-oil as sustainable biofuel, although further refinement is needed to meet current fuel standards.