Emulsification for castor biomass oil

The effect of the emulsifier formula on the stability of castor oil-water system was studied through compounding three groups of emulsifiers from the aspects of stability factor of absorbance,centrifuge stability,demulsification time in quiescence,appearance of the droplets,and viscosity.The best emulsifier formula for castor biomass oil was the composite formula of sorbitan monooleate and polyoxyethylene sorbitan monostearate.Correlation exists between the stability of emulsion and the viscosity/particle size of the droplets,with better stability in the case of greater viscosity or narrower distribution of particle size in the emulsion of castor oil-water system.Methanol added to the castor oil-water system may decrease the viscosity of the emulsion.Comparing the castor oil-water emulsion with methanol-castor oil-water emulsion,the optimal hydrophilic and lipophilic balance(HLB)value based on castor oil-water system was acquired between 6.6 and 7.5,while the optimal HLB value based on the methanol-castor oil-water system was between 5.5 and 6.0.The optimal HLB value of methanolcastor oil-water system gradually moved to that of castor oil-water emulsion with adding more water.

Liquid phase equilibrium of phenol extraction from bio-oil produced by biomass pyrolysis using thermodynamic models

Utilization of biomass as a new and renewable energy source is being actively conducted by various parties. One of the technologies for utilizing or converting biomass as an energy source is pyrolysis, to convert biomass into a more valuable product which is bio-oil. Bio-oil is a condensed liquid from the vapor phase of biomass pyrolysis such as coconut shells and coffee shells. Biomass composition consisting of hemicellulose, cellulose, and lignin will oxidize to phenol which is the main content in bio-oil. The total phenolic compounds contained in bio-oil are 47.03%(coconut shell) and 45%(coffee shell). The content of phenol compounds in corrosive bio-oils still quite high, the use of this bio-oil directly will cause various difficulties in the combustion system due to high viscosity, low calorific value, corrosivity, and instability. Phenol compounds have some benefits as one of the compounds for floor cleaners and disinfectants which are contained in bio-oil.The correlation between experimental data and calculations shows that the UNIQUAC Functional-group Activity Coefficients(UNIFAC) equilibrium model can be used to predict the liquid–liquid equilibrium in the phenol extraction process of the coconut shell pyrolysis bio-oil. While the Non-Random Two Liquid(NRTL) equilibrium model can be used to predict liquid–liquid equilibrium in the extraction process of phenol from bio-oil pyrolysis of coffee shells.

Evaluation of Weed Incidence and Biomass in Coffee Intercropped with Oil Palm in Avenue and Hollow Square Arrangement in Nigeria

Weed incidence and biomass in tree crop plantations are mainly influenced by environmental, farm management practices and cropping systems. Manipulation of intercropping systems to improve weed management in coffee intercropped with oil palm requires a better understanding of spatial and temporal dynamics of weeds. To evaluate the effect of weed incidence and biomass in coffee intercropped with oil palm in avenue and hollow square arrangement, a study was carried out in Cocoa Research Institute of Nigeria (CRIN) in two locations. The locations are Idi-Ayunre (7°25'N, 3°24'E) (an alfisol) and Uhonmora (6°5'N, 5°50'E) (ultisol) in rainforest and derived savannah parts of Nigeria respectively. The experiment had three treatments comprising coffee sole (control), coffee with oil palm (Hollow square) arrangement and coffee with oil palm (Avenue) planting. Coffee was planted 3.0 m apart while oil palm was planted 9 m apart. Equal size of land area was used for coffee in each treatment. The experimental design was Randomized Complete Block (RCBD) with three replicates. Data on vegetative growth of coffee, weed incidence and biomass were taken at three-monthly intervals. The result showed that coffee/oil palm (Hollow Square) had the least weed incidence and biomass closely followed by coffee/oil palm (Avenue) planting. The control had the highest weed biomass which was significantly different from Hollow square and Avenue planting at P ≤ 0.05. The morphological parameters on coffee followed the same pattern but Hollow square arrangement was significantly higher than Avenue and control at P ≤ 0.05.

The Effect of Media on Biomass and Oil Production in Botryococcus braunii Strains Kossou-4 and Overjuyo-3

The green algae Botryococcus braunii is widely recognized as a source of oil, including hydrocarbons. However, the slow rate of growth B. braunii hampers its commercial development. This stu- dy addresses this by examining the effects of three growth media on biomass and oil production in two B. braunii Race B strains, Kossou-4 and Overjuyo-3. Growth of B. braunii strains in BG11 medium resulted in significantly higher growth (2.3 - 4.2 and 2.9 - 6.0 fold increases in Kossou-4 and Overjuyo-3 respectively) compared to the JM and BBM-3N media after 15 days. A similar trend was obtained when biomass was measured indirectly using optical density (OD) and chlorophyll fluo-rescence. Oil production was also significantly higher in BG11 whether measured as oil weight or absorbance (ODs at 680 and 750 nm). However, the presence of extracellular oil was shown to in-crease absorbance values making OD measurements less reliable than dry weight assays. Maximum recovery of oil was recorded when hexane was used as solvent compared to hexane-isopro- panol and heptane. These results suggest that BG11 is the best growth medium for these two strains under the conditions of this experiment.

Production of Bio-Oil from Pyrolysis of Olive Biomass with/without Catalyst

In this study olive biomass was pyrolysis in a 400 cm3 stainless steel reactor. It was externally heated by an electrical furnace in which the temperature is measured by a thermocouple inserted into the bed. The effect of the catalyst ratio to the biomass (5%, 10%, 15%, 20%, 30% and 40%) on the pyrolysis yield was investigated and compared with the uncatalyzed pyrolysis yield product. The bio-oil products yield from the pyrolysis process was found to increase as the catalyst ratio increased. The bio-oil yield from the olive oil-cake, which was 36.1% without the catalyst, reached the maximum value of 39.3% on using activated catalyst at 10% by weight. The gas products yield was found to increase upon using catalyst compared to the non-catalytic pyrolysis. The reduction in the bio-oil yield product was accompanied with a significant reduction in the oxygen content. The pyrolysis oil was examined using chromatographic analysis techniques. The chemical characterization showed that the bio-oil obtained from olive oil cake might be potentially valuable as a fuel and chemical feedstock.

与玉米间作促进苍术根际养分吸收利用的原因

与玉米间作能够缓解苍术连作障碍,而养分条件变化是关键因素之一。为探究苍术||玉米间作对苍术根际养分吸收利用的影响,本研究开展了为期2年的苍术||玉米间作根际不同分隔处理的田间试验,共设置了4种处理:苍术单作(A)、苍术||玉米间作不隔膜(AI)、苍术||玉米间作隔尼龙膜(AN)和苍术||玉米间作隔塑料膜(AP),分别测定了苍术生物量和4种挥发油成分含量,苍术根茎氮磷钾含量,根际土壤pH、有机质和土壤养分因子含量。结果发现,AI和AN处理的苍术根茎鲜重均高于A和AP,且AI与A和AP的差异达显著水平(P<0.05)。苍术4种挥发油含量均表现为AI和AN高于A和AP,其中AI的β-桉叶醇含量分别比A和AP显著高128.4%和205.6%(P<0.05),AI和AN的苍术素含量比A和AP显著提高75.0%~875.0%(P<0.05);相比A和AP,AI和AN的苍术根茎4种挥发油成分总含量显著提高82.8%~210.3%(P<0.05),表明苍术||玉米间作的地下根际互作对促进苍术根茎生物量和挥发油积累有重要作用。AI和AN比A和AP苍术根际土壤pH下降0.4%~6.3%、土壤有机质含量提高13.5%~48.1%;AI的苍术根际土壤碱解氮含量分别比A和AP显著提高32.8%和36.2%(P<0.05),AN的速效钾含量分别显著提高51.5%和46.7%(P<0.05)。相关性分析发现,苍术酮主要与苍术根茎氮磷钾含量和根际土壤氮磷钾含量呈正相关,而苍术素主要与根茎钾含量呈正相关。与A和AP相比,AI苍术磷吸收效率分别提高23.4%和30.0%(P<0.05);AI和AN的氮和钾利用效率比A显著提高131.3%~222.2%(P<0.05)。综上可知,苍术||玉米间作体系中,与无根际互作(A和AP)相比,地下根际互作效应(AI和AN)可提高苍术根际酸化水平,活化土壤氮磷钾,促进苍术根茎养分吸收利用,进而提高苍术产量,同时影响苍术根茎挥发油积累。本研究揭示了苍术||玉米间作地下根际作用是促进苍术根际养分吸收利用的重要因素,为药用植物生态多样性种植模式推广提供重要参考。

木质纤维素类生物质热解转化研究进展

综述了木质纤维素类生物质热解技术的研究进展,总结了不同生物质原料的热解机理,分析了产物的组成和性质,研究了产物的调控、改性和应用。指出未来的研究方向应该集中在以下几方面:技术改进,致力于改进生物质热解技术,提高能源转化效率和产物选择性;产品多样化,除了生物质热解产生的主要能源产品,如生物炭、生物油和生物气,还应着眼于开发高价值的化学品和材料,包括生物基化学品、特殊化学品和高性能材料;集成系统,应尝试将生物质热解与其他能源转化技术相结合,形成多能源联供系统,与生物质发酵、光催化、电解和储能等技术集成,以提高整体能源系统的效率和可持续性。

煤-生物质共热解非催化协同效应特征及机理研究进展

对近年来煤-生物质共热解研究中判定是否发生协同效应及协同效应发生强度的4个指标,即温度范围、热重曲线、表观活化能及热解产物的产率及组成进行总结,并概括包括内在因素和外在因素在内的多种影响因素对煤-生物质共热解非催化协同效应的影响,对煤-生物质共热解非催化协同效应反应机理方面的研究进展和成果进行简要评述。最后提出未来煤-生物质共热解非催化协同效应特征和机理研究中可能面临的挑战。

生物质材料用于油品泄漏应急处置的研究进展

首次综述了国内外对生物质吸油材料的研究进展,包括天然生物质吸油材料、改性生物质纤维和生物质多孔吸油材料,分析了这3类生物质吸油材料在实际应用中的优缺点,并对生物质吸油材料的未来发展方向进行了展望。

原料和热解温度对生物油分子蒸馏分离特性的影响

针对生物油组分复杂,难以直接应用的问题,该研究开展了不同生物油的分子蒸馏馏分分布规律的研究,并考察了不同原料和温度对生物油分子蒸馏分离特性的影响。热解液化试验结果表明,生物油组分以酸、醛、酮、酚、糖为主。随着热解温度的升高,松木生物油中轻质组分产率由21%不断降低至11%,而秸秆生物油中轻质组分产率稳定在20%左右。高温生物油各组分的平均分子自由程两极化程度加强,600℃制备轻质油蒸出比例最高,可以达到92%(松木)和86%(秸秆)。酚类化合物中酚羟基的数量可以影响其分离特性,较高的热解温度促进了酚羟基的产生,从而使酚类物质从蒸出部分(distillation fraction,DF)向残留部分(residual fraction,RF)中转移。分子蒸馏技术能够实现对不同生物油的有效分离,得到的DF中主要包含酸、酮和小分子酚类,RF则以糖和大分子酚为主,除了羟乙醛和苯并呋喃等化合物外,生物油中的大部分化合物的富集程度都可以达到90%以上。该研究可为快速热解生物油的分离及其后续提质研究提供一定的参考。

花生秸秆热解挥发分在HZSM-5负载Ga催化剂上的裂解特性

生物质热解能够将木质纤维素类生物质转化为生物油,但粗油含氧量高、热值低。利用负载Ga的HZSM-5催化剂对生物质热解挥发分进行催化裂解,可以促进生物油的选择性脱氧和芳构化,实现生物油提质。分别采用离子交换法和水热法制备了两种负载Ga的HZSM-5催化剂(Ga-H5-E和Ga-H5-H),采用两段式固定床反应器进行了花生秸秆热解在线联合热解挥发分催化裂解实验。花生秸秆在反应器下段以10℃/min的加热速率从室温升温至700℃,其间逸出的挥发分通过保持在600℃的上段催化剂层进行催化裂解。结果表明,相比无负载的HZSM-5,Ga-H5-E和Ga-H5-H使BTX(苯、甲苯和二甲苯)产率分别提高了77%和93%,其中甲苯和二甲苯的增加尤为明显。采用热重分析仪、电感耦合等离子发射光谱仪、X射线衍射仪、扫描电子显微镜、能量色散X射线光谱仪、比表面积分析仪和化学吸附仪等对催化剂进行了表征分析。结果表明,两种Ga负载催化剂的积炭产率显著低于原催化剂(HZSM-5);Ga负载使催化剂强酸位显著增多,有利于增加脱氧反应的催化活性中心;相比于Ga-H5-E,Ga-H5-H含有容积较大的介孔和较小的平均孔径,而且更多Ga浸入了颗粒内部,这些差异可能促进乙烯和丙烯在介孔内发生芳香化反应,从而提高了单环芳香烃产量。

Crown evolution kinematics of a camellia oil droplet impacting on a liquid layer

The phenomenon of droplet impact on an immiscible liquid is encountered in a variety of scenarios in nature and industrial production. Despite exhaustive research, it is not fully clear how the immiscibility of the liquid on which a droplet impacts affects the crown evolution. The present work experimentally investigates the evolution kinematics of a crown formed by the normal impact of a camellia oil droplet on an immiscible water layer. Based on discussion of dynamic impact behaviors for three critical Weber numbers(We), the radius of the crown and its average spreading velocity are compared with those of previous theoretical models to discuss their applicability to the immiscible liquid. The evolution kinematics(morphology and velocity) are analyzed by considering the effects of the We and layer thickness. Furthermore,the ability of crown expansion in radial and vertical directions is characterized by a velocity ratio. The results show that our experimental crown radius still follows a square-root function of evolution time, which agrees with the theoretical predictions. The dimensionless average spreading velocity decreases with We and follows a multivariate power law, while the dimensionless average rising velocity remains constant. The velocity ratio is shown to linearly increase with We,demonstrating that the rising movement in crown evolution gradually enhances with We. These results are helpful for further investigation on the droplet impact on an immiscible liquid layer.

Ga、Zn改性ZSM-5对生物质热裂解产物单环芳烃选择性的影响

针对生物油组分复杂、含氧量高等问题,通过使用金属改性催化剂改善生物油的组成,提高生物油中单环芳烃(Monocyclic Aromatics Hydrocarbon,MAHs)的选择性,并探讨了生物质催化热裂解反应机理。以硝酸镓、硝酸锌为改性剂,采用离子交换法对不同硅铝比的ZSM-5进行改性,使用Py-GC/MS外标法探究硅铝比(30、40、50和60)和金属元素类型(Ga、Zn)对玉米秸秆催化热裂解产物单环芳烃选择性的影响。结果表明,对于Ga/ZSM-5,硅铝比为30时更有利于单环芳烃的产生,此时玉米秸秆催化热裂解产物单环芳烃的相对含量为19.02%,是在母体ZSM-5(30)催化下的1.38倍;对于Zn/ZSM-5,硅铝比为40时更有利于单环芳烃的产生,此时玉米秸秆催化热裂解产物单环芳烃的相对含量为22.18%,是在母体ZSM-5(40)催化下的1.51倍。硅铝比对二甲苯、萘和二甲基萘的产率影响比改性金属元素影响大,改性金属元素对苯、甲苯和茚的产率影响比硅铝比影响大。从生物油的相对含量、元素组成、芳香烃的相对含量、以及单环芳烃的产率来看,Zn/ZSM-5(40)的催化效果优于Ga/ZSM-5(30)。

基于全生命周期的生物质热解液化技术经济评价

在“双碳”目标背景下,通过对生物质热解液化制备生物油生产链条的生命周期技术经济评价,开拓生物汽柴油生产方式,为缓解我国原油进口“卡脖子”问题寻求新出路。从生物油厂建设到运营寿命期终止整个过程中,静态投资回收期为5.46年,动态投资回收期为7.45年,内部收益率为17%,累计净现值为2021.491万元。若项目生产成本、生产能力和销售能力与预期值相同,产品销售价格(生物柴油)不低于6105.81元·t^(-1)时,才能避免发生亏损。相对于电耗价格,该项目对原料价格敏感性更低,且需要生产规模大于1700 t才能实现项目的有效盈利。生物油厂进一步降低能耗和原料价格对其生存和发展至关重要,同时稳定廉价的原料供给也是企业竞争的关键所在。

N_(2)/CO_(2)气氛下木屑生物质热解特性的实验研究

本研究利用固定床管式炉开展了不同N_(2)/CO_(2)比例气氛下的木屑生物质热解实验,考察了CO_(2)浓度、载气流速和停留时间对热解油和焦炭产率的影响。结果表明:热解油和焦炭的产率随反应温度和停留时间的增加而降低,热解油产率随反应气氛中CO_(2)浓度的升高而增加。在N_(2)和CO_(2)气氛下,载气流速升高均使热解油产率下降,而焦炭产率则在15%左右保持不变。添加HZSM-5和ZIF-67两种催化剂,发现ZIF-67在CO_(2)气氛下的热解油产率可以达到72.3%,相比其在N_(2)气氛下的热解油产率提升了近1.5倍;而HZSM-5由于其微孔孔道对生物质大分子传质的限制,产生最多焦炭(24.1%)。

灰分中碱和碱土金属对生物质快速热解生物油组分的影响

生物质灰分中的碱和碱土金属(AAEMs)对快速热解生物油的产率和组分分布具有显著影响。本研究选取玉米秸秆为原料,研究梯级脱灰预处理(蒸馏水、醋酸铵和盐酸)对AAEMs的选择性脱除及其生物油组分的影响,研究了碱和碱土金属类别(K、Ca、Na和Mg)、盐质量分数(0.5%、2.5%、5%)和不同钾盐的酸根(SO_(4)^(2-)、NO_(3)^(-)、CO_(3)^(2-)、HCO_(3)^(-)、AC^(-)、PO_(4)^(3-))对生物油组分的影响。结果表明,在梯级脱灰预处理过程中,随着脱灰溶液酸性程度加深,AAEMs的脱除率逐渐上升,根据AAEMs在梯级脱灰过程中的选择性脱除规律,可将其在生物质中的赋存形态分为水溶性(K)、离子交换性(Ca和Mg)和酸溶性(Na)等形态。经过碱和碱土金属盐浸渍后,AAEMs将起到催化剂的作用,促进热解中间产物左旋葡聚糖的二次降解,导致其相对含量显著降低,形成更多的呋喃和酮类等轻质含氧化合物,导致2,3-二氢苯并呋喃、酮类和长链烷烃等组分的含量显著增加。不同钾盐酸根离子对脱水糖的二次裂解反应及木质素芳基醚键和酚羟基的裂解反应具有较大的影响,根据酸根的酸性强弱,对脱水糖裂解反应的影响大小顺序为HCO_(3)^(-)>CO_(3)^(2-)>AC^(-)>PO_(4)^(3-)>Cl^(-)>NO_(3)^(-)>SO_(4)^(2-),而对木质素芳基醚键和酚羟基的裂解反应影响大小顺序为CO_(3)^(2)->Cl^(-)>HCO_(3)^(-)PO_(4)^(3-)≈AC^(-)>SO_(4)^(2-)≈NO_(3)^(-).

生物质预处理催化热解制备液体燃料研究进展

随着能源需求的不断增长和环境问题的日益突出,生物质催化热解制备液体燃料技术成为一种可持续发展的能源利用方式。生物质直接热解生成的生物油成分复杂、热值低、含氧量高、酸性强,制约了生物油的应用。从热解机理、生物质预处理、催化剂和预处理和催化耦合技术等方面综述了影响生物油品质的主要因素。指出预处理技术普遍存在时间长的缺点,使用催化剂会导致生物油产率的降低,而预处理和催化耦合技术有望突破这2项技术难点;生物质快速热解定向制备富烃生物油、催化剂的选择与优化、预处理和催化耦合技术将是生物质快速热解制备高品质液体燃料的主要研究方向。

Photocatalytic degradation of organic pollutants using green oil palm frond-derived carbon quantum dots/titanium dioxide as multifunctional photocatalysts under visible light radiation

The present work suggested the use of waste oil palm frond as an alternative precursor for nitrogendoped carbon quantum dots(NCQDs)and proposed a straightforward in-situ hydrothermal method for the preparation of NCQDs/TiO_(2)nanocomposites.The elemental composition,morphological,structural and optical characteristics of NCQDs/TiO_(2)nanocomposites have been comprehensively investigated.The successful grafting of NCQDs on TiO_(2)matrix was confirmed by the formation of Ti AOAC bond and the electronic coupling between theπ-states of NCQDs and the conduction band of TiO_(2).For the first time,the oil palm frond-derived NCQDs/TiO_(2)was adopted in the photodegradation of methylene blue(MB)under visible-light irradiation.As a result,the photocatalytic efficiency of NCQDs/TiO_(2)nanocomposites(86.16%)was 2.85 times higher than its counterpart TiO_(2)(30.18%).The enhanced performance of nanocomposites was attributed to the pivotal roles of NCQDs serving as electron mediator and visiblelight harvester.Besides,the optimal NCQDs loading was determined at 4 ml while the removal efficiency of NCQDs/TiO_(2)-4 was the highest at a catalyst dosage of 1 g.L^(-1)under alkaline condition.This research work is important as it proposed a new insight to the preparation of biomass-based NCQDs/TiO_(2)using a facile synthetic method,which offers a green and sustainable water remediation technology.

Toluene degradation by a water/silicone oil mixture for the design of two phase partitioning bioreactors

Toluene degradation performances were studied in a 10 L Two-Phase Partitioning Bioreactor(TPPB).The liquid phase consisted of a mixture of water and PDMS 50(Poly Di Methyl Siloxane,i.e.silicone oil,viscosity of 46 m Pa·s) in the volume ratio of 75%/25%.Two series of experiments were carried out:in the first,the reactor was sequentially supplied with toluene whereas in the second,toluene was continuously supplied.Activated sludge from the wastewater treatment plant of Beaurade(Rennes,France) was used at an initial concentration of 0.5 dry mass g·(mixture L)^(-1).The elimination capacity(EC) was investigated as well as the change in biomass concentration over time.Toluene biodegradation was very ef ficient(removal ef ficiency,RE=100%) for toluene flows ranging from 0.2 to 1.2 ml·h^(-1),corresponding to elimination capacities of up to 104 g·m^(-3)·h^(-1).For a toluene flow of 1.2 ml·h^(-1),the biomass concentration measured at the end of the experiment was 4.7 dry mass g·(mixture L)^(-1).The oxygen concentration in the liquid phase was clearly not a limiting factor in these operating conditions.Based on these results,an extrapolation leading to the design of a large-scale pilot TPPB can now be considered to study toluene degradation performances in industrial conditions.