Hydrothermal catalytic liquefaction mechanisms of agal biomass to bio-oil

The liquefaction mechanisms of the algal biomass to bio-oil were investigated by using Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy, respectively. It was found that NaOH was a satisfactory catalyst and contributed to helping the liquefaction of algal biomass. The bio-oil from algal biomass was composed of many compounds, including carbohydrates, alcohol, hydroxybenzene, carboxylic acid, alkene, ester, and others. The mechanism of hydrothermal catalytic liquefaction was discussed. It was found that, comparing with the husk bio-fuel, the algal bio-oil as a promising alternative fuel was more close to the traditional diesel fuel in physicochemical properties. The novel research outcomes contribute to improving the yield of bio-oil from microalgae, reducing the cost of the bio-oil and accelerating the commercial application of the algal bio-oil in the near future.     

Ball milling promoted direct liquefaction of lignocellulosic biomass in supercritical ethanol

In the present work, ball milling was applied for the pretreatment of lignocellulose to obtain high conversion and bio-oil yield in supercritical ethanol. Ball milling substantially decreased the crystallinity and particle size of lignocellulose, thereby improving its accessibility in ethanol solvent. An increased bio-oil yield of 59.2% was obtained for the ball milled camphorwood sawdust at 300°C, compared with 39.6% for the original lignocellulose. Decreased crystallinity significantly benefited the conversion of the cellulose component from 60.8% to 91.7%, and decreased particle size was beneficial for the conversion of all components. The obtained bio-oil had a high phenolic content, as analyzed by gas chromatography-mass spectrometry. Methoxylation and retro-aldol condensation were observed during alcoholysis, and the reaction pathways of lignocellulose in supercritical ethanol were attributed to the action of free radicals.     

Acetic Acid Recovery from Fast Pyrolysis Oil. An Exploratory Study on Liquid-Liquid Reactive Extraction using Aliphatic Tertiary Amines

Abstract

Flash pyrolysis oil or Bio-oil (BO), obtained by flash pyrolysis of lignocellulosic biomass, is very acidic in nature. The major component responsible for this acidity is acetic acid, present in levels up to 2–10 wt%. Here, we report an exploratory study on BO upgrading by reactive extraction of acetic acid using long-chain tertiary amines in a batch set-up. Factors affecting the extraction efficiency, such as the type and concentration of tertiary amine and co-solvents, were investigated. More than 90 wt% of the acetic acid could be extracted in a single equilibrium step (BO diluted in THF (26 wt% BO), trioctylamine (TOA) in octane as the extractant phase, T = 20°C). However, the amine has considerable affinity for the BO phase and about 10 wt% on initial intake was transferred to the BO. A considerable improvement was obtained when using the aqueous phase of a thermally treated BO containing 6 wt% acid of acetic acid. In a single extraction step, acetic acid extraction efficiencies up to 75 wt% were achieved without significant amine transfer to the aqueous phase.     

柠檬酸改性Pt/Al-MCM-41催化麻疯树籽油 一步加氢制备燃油组分

采用0.25 mol/L柠檬酸浸渍处理Al-MCM-41后负载Pt制备成新型催化剂，并采用XRD、TEM、XRF、NH3-TPD和Py-IR对改性催化剂进行表征。以麻疯树籽油为原料，在微型高压固定床催化剂反应评价装置上，以空速1.0 h-1、氢油比1 000、氢压4 MPa、柠檬酸改性催化剂Pt/Al-MCM-41用量6 mL以及不同温度进行一步加氢催化制备燃油组分，通过GC-MS对产物进行定性定量分析。结果表明：柠檬酸降低了Al-MCM-41分子筛骨架的有序度，部分Al被脱除，催化剂比表面积降低、但提高了催化剂孔容、孔径，形成了微孔，其酸性也有了显著改变；当加氢反应温度为360 ℃时，产物的脱氧率为87.11%，C9~C14烷烃相对含量为5.59%，C15~C16烷烃相对含量为34.55%，C8~C16异构烷烃相对含量为14.12%，C8~C16芳烃相对含量为3.12%，C17~C18烷烃相对含量为60.48%。柠檬酸改性催化剂Pt/Al-MCM-41对催化麻疯树籽油加氢反应的短链烷烃选择性较低。     

Bio-oil Production from an Oilseed By-product: Fixed-bed Pyrolysis of Olive Cake

Abstract

A study of pyrolysis of olive cake at the temperature range from 400°C to 700°C has been carried out. The experiments were performed in a laboratory scale tubular reactor under nitrogen atmosphere. The yields of derived gases, liquids, and char were determined in relation to pyrolysis temperature and sweeping gas flow rates, at heating rates of about 300°C min^?1. As the pyrolysis temperature was increased, the percentage mass of char decreased whilst gas product increased. The oil products increased to a maximum value of ～39.4 wt% of dry ash free biomass at a pyrolysis temperature of about 550°C in a nitrogen atmosphere with flow rate of 100 mL min^?1 and with a heating rate of 300°C min^?1. Results showed that the bio-oil obtained under the optimum conditions is a useful substitute for fossil fuels or chemicals.     

Producing Bio-oil from Olive Cake by Fast Pyrolysis

Abstract

This article reports on physico-chemical properties of olive cakes to evaluate them as a raw material in energy production through thermo-chemical pyrolysis conversion process. The present study focuses on the actions related to the possibilities to utilize in particularly olive cake as an agricultural residue. Olive cake is a very promising material for the production of bio-oil. Liquid, solid, and gaseous products were obtained from olive cake by pyrolysis. If the purpose were to maximize the yield of liquid products resulting from biomass pyrolysis, a low temperature, high heating rate, and short gas residence time process would be required. Flash pyrolysis gives high oil yields. The heating was carried out from 298 K to 1,050 K in the absence of oxygen. The yields of liquid products were obtained from the olive cake by pyrolysis for the runs of different heating rates: 10 K/s, 20 K/s, and 40 K/s. The highest bio-oil yields from the olive cakes were 31.0% at 700 K, 36.0% at 700 K, and 41.0% at 700 K obtained from 10 K/s, 20 K/s, and 40 K/s heating rate runs, respectively. The highest bio-oil yields olive stone shells were 27.0% at 700 K, 31.0% at 700 K, and 34.5% at 750 K obtained from 10 K/s, 20 K/s, and 40 K/s heating rate runs, respectively.     

生物油再生剂热再生老化SBS改性沥青及混合料性能研究

基于针入度指标体系试验和路用性能研究了生物油再生剂热再生老化SBS沥青胶结料及其混合料的路用性能,以技术性能接近SBS改性沥青(I-C)为指标,确定了生物油再生剂的最佳掺量。试验结果表明:随着生物油再生剂掺量的增加,再生SBS改性沥青的低温性能和弹性恢复率提高,但高温性能降低;掺加生物油可提高热再生混合料的低温抗裂性能、水稳定性和抗疲劳耐久性,但掺量过多会显著降低热再生混合料的高温抗车辙变形能力。生物油可作为芳烃油再生剂的替代产品,生物油再生剂的适宜掺量为老化SBS改性沥青质量的9%~12%。     

猪体水热液化工艺参数优化及生物油特性分析

以猪体为原料,以高位热值、C元素回收率、N元素残留率作为生物油质量指标,采用响应面法研究反应温度（220~300 ℃）、反应时间（40~80 min）、固含量（10%~30%）对猪体水热转化生物油产率与质量的影响。研究结果表明：反应条件均会影响水热反应的进行且温度影响最显著,分别在不同反应条件下得到单一指标最优的生物油;生物油的最大产率为76.94%（278 ℃、64 min、29%固含量）,最大HHV值为38.63 MJ/kg（290 ℃、47 min、30%固含量）,最大C元素回收率为93.16%（260 ℃、60 min、10%固含量）,最低N元素残留率为15.52%（220 ℃、40 min、12%固含量）。生物油的元素分析结果表明水热液化可有效降低生物油中N、O元素含量,提高生物油品质。傅里叶变换红外光谱分析与热重分析结果表明,生物油的化学成分复杂且以分子量较大、碳链较长的有机物为主。     

生物质快速热解生物油产率和组分的影响因素

生物质快速热解是能源转化中效率较高的一种。本文从物料特性(物料组成、粒径、含水率)和反应条件(升温速率、反应温度、滞留时间、压力和催化剂)两方面对影响生物油产率和组分进行论述,分析了影响生物油组分的主要因素:物料组成、反应温度和催化剂,对影响生物油产率的主要因素物料粒径、温度和气体停留时间进行阐述。