漆籽中漆籽油和漆蜡的提取和初步表征(英文)

研究漆籽油和漆蜡提取的最佳工艺,进行单因素实验,对不同品种漆油进了红外分析。结果表明:漆蜡的最佳工艺条件是:石油醚(30℃～60℃)作为提取剂,提取温度为50℃,固液比为1∶20,提取时间12h,漆籽皮的目数是大于100目;漆油的最佳工艺条件是:石油醚(30℃～60℃)作为提取剂,提取温度为50℃,固液比为1∶30,提取时间3h,漆籽皮的目数是大于100目。通过萃取所得的漆油在红外图谱上出峰位置基本一致,表明其化学成分基本相同。     

生物油中提取热解木质素的性质分析(英文)

Bio-oil is a new liquid fuel produced by fast pyrolysis, which is a promising technology to convert biomass into liquid. Pyrolytic lignin extracted from bio-oil, a fine powder, contributes to the instability of bio-oil. The paper presents the structural features of three kinds of pyrolytic lignin extracted from bio-oil with different methods (WIF, HMM, and LMM). The pyrolytic lignin samples are characterized by Fourier transform infrared spectrometer (FTIR) and X-ray photoelectron spectroscopy (XPS). FTIR data indicate that the three pyrolytic lignin samples have similar functional groups, while the absorption intensity is different, and show characteristic vibrations of typical lignocellulosic material groups O H (3340-3380 cm1), C H (2912-2929 cm1) and C O (1652-1725 cm1). Comparison in the region (3340-3380 cm1) indicates that WIF has more O H stretch groups than HMM and LMM. The carbon spectra are fitted to four peaks: C1, C C or C H, BE 283.5 eV; C2, C OR or C OH, BE 284.5-285.8 eV; C3, C O or HO C OR, BE 286.10-287.10 eV; C4, O C O, BE 287.5-287.7 eV. The absence of C1, C C or C H indicates the dominant polymerization structure of aromatic carbon in pyrolytic lignin samples. For HMM and WIF, C2a and C2b can not be separated, so there is no free hydroxyl group in the samples. The oxygen peaks are also fitted to four peaks: O1, OH, BE = 530.3 eV; O2, RC O, BE 531.45-531.72 eV; O3, O C O, BE = 532.73-533.74 eV; O4, H2O, BE 535 eV. The absence of O1 and O4 indicates that little hydroxyl groups and adsorbed water are present in the samples.     

旋转填料床中硝酸吸收NO_x的实验研究(英文)

Absorption of NOx into nitric acid solutions was studied in the presence of ozone by using a rotating packed bed (RPB) contactor. The influences of operating parameters, such as high gravity number, amount of ozone, gas velocity, liquid spray density and inlet concentration of NOx, on the removal efficiency of NOx were investigated, among which the high gravity number and ozone amount are more important. Ozone was introduced to oxidize HNO2 to HNO3 to prevent the decomposition of HNO2 in the liquid phase. The high gravity number presents the effective external force for enhancing the mass transfer of ozone from gas phase to liquid phase. Under the experimental condition, the removal efficiency of NOx is higher than 90% and the concentration of nitric acid product exceeds 45%.     

伴随传质的液液体系微分散流型图的实验研究(英文)

This paper presents the experimental results of liquid-liquid microflows in a coaxial microfluidic device with mass transfer.Three working systems were n-butanol + phosphoric acid(PA) + water,methyl isobutyl ketone(MIBK) + PA + water,30% kerosene in tri-n-butylphosphate(TBP) + PA + water.The direction and intensity of mass transfer were adjusted by adding PA in one of two phases mutual saturated in advance.When PA transferred from the organic phase to the aqueous phase,tiny aqueous droplets may generate inside the organic phase by mass transfer inducement to form a new W/O/W flow pattern directly on some special cases.Once the PA concentration was very high,violent Marangoni effect could be observed to throw part of organic phase out of droplets as tail.The interphase transfer of PA could expand the jetting flow region,in particular for systems with low or medium inter-facial tension and when the mass transfer direction was from the aqueous phase to the organic phase.     

旋转填充床中沉淀过程的模型及实验验证(英文)

A mixing-precipitation model based on the modified coalescence-redispersion model was presented to describe the flow, mixing, nucleation and growth in a rotating packed bed (RPB). The model was coupled with population balance, mass balance and crystallization kinetics. It predicted well the influence of coalescence probability, which represents the mixing intensity among drop-lets, on the particle number density, supersaturation and mean particle size of the produced precipitates. The effects of the radial thickness of packing, liquid flow rate and rotating speed on the product particle size were also investigated. The results indicate that the needed radial length of packing is short for sparingly soluble substance precipitation (about 40-50 mm in this work), and the mean particle size of precipitates decreases with the increase of rotating speed and liquid flow rate, respectively. The validity of this model was verified by experiment on BaSO4 precipitation in RPB.     

恒热流直管中纳米流体对流传热的实验研究(英文)

In this work, the laminar convective heat transfer performance and the pressure drop of water-based nanofluids containing Al2O3, TiO2 and SiO2 nanoparticles flowing through a straight circular tube were experimen-tally investigated. The experimental results showed that addition of small amounts of nano-sized Al2O3 and TiO2 particles to de-ionized water increased heat transfer coefficients considerably, while the SiO2 nanofluids showed the opposite behavior attracting the authors’ interests. An average of 16%and 8.2%increase in heat transfer coefficient were observed with the average of 28%and 15%penalty in pressure drop for Al2O3 and TiO2 nanofluids.     

原子转移自由基聚合体系中催化剂的脱除与回收(英文)

用原位吸附法除去了ＡＴＲＰ聚合体系中的催化剂,对所选吸附剂的研究结果表明：纯化后的聚合物铜含量不大于１０×１０－６,含ｂｐｙ的吸附剂同碱液共热后,ｂｐｙ易于和水一起蒸出,经乙醚萃取、真空干燥得熔程为６８～７２℃的纯ｂｐｙ。     

二氧化碳-水气液相平衡体系在湍流中的平衡偏移Ⅰ:实验与关联式(英文)

The carbon dioxide-water system was used to investigate the flowing gas-liquid metastable state.The experiment was carried out in a constant volume vessel with a horizontal circulation pipe and a peristaltic pump forced CO2 saturated water to flow.The temperature and pressure were recorded.The results showed that some CO2 escaped from the water in the flow process and the pressure increased,indicating that the gas-liquid equilibrium was broken.The amount of escaped CO2 varied with flow speed and reached a limit in a few minutes,entitled dynamic equilibrium.Temperature and liquid movement played the same important role in breaking the phase equilibrium.Under the experimental conditions,the ratio of the excessive carbon dioxide in the gas phase to its thermodynamic equilibrium amount in the liquid could achieve 15%.     

两相更新支撑液膜中金属二价镍的迁移行为研究(英文)

A novel disphase supplying supported liquid membrane(DSSLM),containing supplying feed phase and supplying stripping phase for transport behavior of Ni(II),have been studied.The supplying supported feed phase included feed solution and di(2-ethyhexyl) phosphoric acid(HDEHP) as the carrier in kerosene,and supplying stripping phase included HDEHP as the carrier in kerosene and HCl as the stripping agent.The effects of volume ratio of membrane solution to feed solution(O/F),pH,initial concentration of Ni(II) and ionic strength in the feed solution,volume ratio of membrane solution to stripping solution(O/S),concentration of H2SO4 solution,HDEHP concentration in the supplying stripping phase on transport of Ni(II),the advantages of DSSLM compared to the traditional supported liquid membrane(SLM),the system stability,the reuse of membrane solution and the reten-tion of membrane phase were studied.Experimental results indicated that the optimum transport of Ni(II) was ob-tained when H2SO4 concentration was 2.00 mol·L-1,HDEHP concentration was 0.120 mol·L-1,and O/S was 4:1 in the supplying stripping phase,O/F was 1︰10 and pH was 5.20 in the supplying feed phase.The ionic strength in supplying feed phase had no obvious effect on transport of Ni(II).When initial Ni(II) concentration was 2.00×10?4 mol/L,the transport percentage of Ni(II) was up to 93.1 % in 250 min.The kinetic equation was deduced in terms of the law of mass diffusion and the interface chemistry.     

稻秸秆提取腐植酸残渣基生物炭的制备及其对水体中Cr(Ⅵ)吸附性能研究

以稻秸秆提取腐植酸残渣(ER)与工业尾矿渣(TR)为原料进行共热解制备出一种生物炭,并将其应用于含Cr(Ⅵ)废水的吸附。对主要热解及吸附因素进行了分析,并对吸附机理进行了初步探究。结果表明,生物炭的最佳热解及吸附条件为700℃、ER∶TR=2∶1、投加量为1 g/L、pH=2。在此条件下,当Cr(Ⅵ)初始浓度<30 mg/L,Cr(Ⅵ)去除率在5 min时即可达99%。生物炭的吸附过程符合Langmuir等温线方程,饱和吸附量为27.05 mg/g;准二级动力学方程能更好地反映生物炭的吸附过程,吸附以化学吸附为主。Cr(Ⅵ)首先在静电作用下吸附在生物炭表面,然后Cr(Ⅵ)在生物炭表面被单质碳或溶液中的H⁺还原为Cr(Ⅲ),最后Cr(Ⅲ)在生物炭表面与官能团络合。     

Extraction of metals from automotive shredder residue:Preliminary results of different leaching systems

The study is focused on the extraction of valuable metals from automotive shredder residue (ASR) by different leaching solutions. First, ASR samples were roasted at 600 °C to simulate a thermal treatme...     

Influence of carbonation and carbonation methods on leaching of metals from mortars

Mortars with varying water-to-cement (w/c) ratio were spiked with heavy metals. After hardening, some samples were carbonated in a CO₂ chamber, others were carbonated using supercritical CO₂ (SCC). Porosity and carbonation depth of treated and untreated samples were compared. Leaching was tested using the diffusion (NEN 7345) and extraction test (based on DIN 38414-S4). The results show that carbonation decreases the porosity of the samples. The decrease is more important with increasing w/c ratio. Carbonation runs deeper into the monolith with increasing w/c ratio. In the supercritical method, not all samples were carbonated to the same extent. The diffusion test shows that carbonation decreases leaching of Na, K, Ca, Ba, Cu, and Pb and increases leaching of Mg. Ni leaching depends on the pH induced by carbonation. Influence of pH and formation of metal carbonates is evaluated with the extraction test and enhances understanding of metal leaching in the diffusion test.     

Agglomeration problems during fluidized bed gasification of olive-oil residue: evaluation of fractionation and leaching as pre-treatments

The effect of two pre-treatment techniques leaching and fractionation on the agglomeration problems observed during the gasification of the olive-oil residue material in a fluidized bed reactor was studied. The obtained results proved to be very positive in the case of leaching showing a substantial decrease of the agglomeration phenomena in the bed during the gasification tests compared with the results from the tests with the un-treated material. On the other hand, fractionation appeared to increase the ash reactivity leading to a dramatic increase of the agglomeration problems during the gasification process.     

Phosphorus status of soil and leaching losses: results from operating and dismantled lysimeters after 15 experimental years

The objectives of the present study were: (1) to evaluate the predicting value of the most important European soil P tests for P leaching losses; and (2) to investigate how these soil P tests reflect the development of P depth profiles in original homogeneous soils of lysimeters. The study included more than 100 lysimeters, located at the Lysimeter Station Falkenberg/Saxony-Anhalt, UFZ-Centre for Environmental Research Leipzig-Halle GmbH, Germany. Soil textures were sand, sandy loam, loam and silt. The management forms were arable land, grassland and fallow with various variation in fertilisation, crop rotation and irrigation. Samples were collected from the A-horizons and from the whole profiles of eight set-aside and dismantled lysimeters at 10-cm sections. The concentrations of total P were determined monthly in the leachates and evaluated for a three-year period. The concentrations of P extracted by ammonium acetate lactate (AL-P), double lactate (DL-P), sodium bicarbonate (Olsen-P) and ammonium oxalate (OX-P) as well as P_t were significantly correlated with each other (P<0.05–P<0.001) for arable soils. The relevant regression coefficients were strongly influenced by soil texture, soil use and management. The mean annual P concentrations of the leachates were in the range 0.4–1.2 mg l^–1 for sands and <0.001–0.1 mg l^–1 for the textures sandy loam, loam and silt. These corresponded to P leaching losses of 0.001–2846 g ha^–1 yr^–1. Mean annual and maximum P concentrations and leaching losses were significantly (r>0.954, P<0.001) predicted by the OX-P concentrations of arable topsoils in lysimeters filled with sand. For sandy loam under grass the agronomic soil P tests (AL-P, DL-P and Olsen-P) enabled reasonable predictions of P in leachate. Under arable use, factors such as fertilisation, management intensity, depth of tillage and irrigation resulted in weak correlations between soil P concentrations and P in leachate. It was shown for the first time that all P extractants reflected P enrichments in topsoils and subsoils and the development of distinct depth profiles. Influence of soil use on the depth distribution of P was more pronounced in the 0–20 cm layer than in the subsoils. Here, the original homogeneous substrate had oscillating P concentrations at 10-cm increments under all soil uses. These could not be explained by Al_ox and Fe_ox but were significantly correlated with the C_t contents and bulk density. This indicates that vertical movement of P containing organic matter along with differences in porosity contributed to the heterogeneous P distribution in the lysimeter subsoils. This new evidence must be considered if data sets from long-term lysimeter experiments are used to calibrate and validate P leaching models.     

铬渣中六价铬浸出方法对比实验研究

铬渣是一种环境污染极大的工业废渣,其中的六价铬是国际公认的致癌物,但如何科学评价铬渣中六价铬的含量及其危害性却很困难。通过实验对比了4种标准方法（USEPA 3060A、HJ/T 299-2007《固体废物 浸出毒性浸出方法 硫酸硝酸法》、HJ/T 300-2007《固体废物 浸出毒性浸出方法 醋酸缓冲溶液法》和GB 5086.2-1997《固体废物 浸出毒性浸出方法 水平振荡法》）对铬渣中六价铬的浸出效果,还比较了恒定pH条件下不同酸液及组合两步浸取的浸出效果。实验结果表明,标准的酸液浸出法难以有效浸出铬渣中的六价铬,除非破坏铬渣中的物相结构,否则任何浸出方法都无法完全浸出铬渣中的六价铬。     

Transesterification of sunflower oil over zeolites using different metal loading: A case of leaching and agglomeration studies

The aim of this study was to analyse the catalytic performance of several heterogeneous catalysts in the transesterification of sunflower oil with methanol. In order to characterize the different catalysts, nitrogen adsorption/desorption and CO₂ temperature programmed desorption were used. The transesterification of sunflower oil was carried out using three different zeolites: mordenite, beta and X, to determine the influence of the kind of zeolite on the methyl ester production. The influence of the metal incorporation technique was studied using both impregnation and ion-exchange methods. Also, the transesterification reaction was carried out using catalysts with different metal loading. Finally, zeolite X was agglomerated with a binder, sodium bentonite, to study how the presence of a binder could change the catalytic performance of the zeolite. A methyl ester content of 93.5 and 95.1 wt% was obtained at 60 °C employing zeolite X with or without sodium bentonite, respectively. All biodiesel synthesized were characterized using the standard UNE-EN 14214. A complete deactivation study was carried out in order to check the sodium leaching from the catalyst. The results supported the hypothesis of a homogeneous-like mechanism where the alkali methoxide species were leached out.     

Acid reducing leaching of cathodic powder from spent lithium ion batteries: Glucose oxidative pathways and particle area evolution

Co and Li recovery by acid-reducing leaching of lithium ion battery powder was investigated evidencing that glucose efficiency changes depending on leaching procedure. Postponing glucose addition metal extractive yields were higher (88% for Co and 92% for Li) than adding glucose at the beginning (60% for both). Chromatographic analyses evidenced that glucose degradation occurred preferentially via glucaric acid when its addition is postponed, while gluconic via is favored if glucose is added initially. Dynamic evolution of particle area showed particle fragmentation occurring during acid preleaching determining an increase of specific surface area available for further reaction when glucose is added.     

Chromate leaching from inhibited primers: Part I. Characterisation of leaching

Leaching and characterisation studies have been undertaken on two chromate-inhibited epoxy polyamide primers. Leaching was carried out in 5% (w/v) NaCl solutions at different pH values (1, 3, 5 and 7) and the amount of Cr released into solution was monitored over time. Cr release was initially high, but as the immersion time increased the leaching from the primers slowed. Prior to and after immersion, the primers were characterised by a number of techniques including electron microprobe analysis, X-ray microdiffraction, Raman spectroscopy, and positron annihilation lifetime spectroscopy. The unexposed primers were found to contain the inorganic phases SrCrO₄, BaSO₄ and TiO₂ (anatase or rutile). Upon immersion, water uptake by the primers was observed, together with a decrease in the amount of SrCrO₄ in the primers. These studies provide insights into the mechanism of chromate leaching from inhibited primers.     

Studies on rejuvenation of spent residue hydroprocessing catalysts by leaching of foulant metals: influence of inorganic salt additives on the leaching efficiency of organic acids

A comparative study has been made on the efficiency of oxalic, malonic and acetic acids for selective removal of metal foulants (e.g. vanadium) from spent residue hydrotreating catalysts in the presence and absence of aluminium nitrate. The influence of concentration of the added salt (aluminium nitrate) on the leaching efficiency of the three acids was also studied. The treated catalysts were characterized and the improvements in surface area, pore volume and HDS activity as a result of leaching with each reagent compared. The studies revealed that addition of aluminium nitrate enhanced the leaching efficiency of each acid to a different degree. The rate of vanadium leaching by oxalic acid was increased substantially by aluminium nitrate addition whereas for acetic acid there was only a moderate enhancement in leaching rate. The enhanced leaching by the aluminium nitrate-organic acid system may be explained in terms of a synergistic mechanism involving oxidizing and complexing reactions. The improvement in surface area and pore volume achieved on rejuvenation were related to the extent of removal of vanadium from the catalyst. The HDS activity of the catalyst was also increased significantly by leaching of the deposited metals. The selectivity for vanadium leaching (V/Mo ratio) was found to be an important factor for HDS activity recovery.     

A comparative study of different leaching processes for the extraction of Cu,Ni and Co from a complex matte

The extraction behaviors of Cu, Ni and Co from a complex matte under different leaching conditions have been discussed. The synthetic Cu-Ni-Co-Fe-S matte was prepared by melting the pure metals. The matte contained 24.95% Cu, 35.05% Ni, 4.05% Co, 11.45% Fe, 24.5% S, similar composition as is expected to be obtained by reduction smelting of the Pacific Ocean nodules followed by sulphidisation of the alloy. The different phases identified are CuFeS₂, CuS₂, (FeNi)₉S₈, (FeNi)S₂, Ni₉S₈, Ni₃S₂, (CoFeNi)₉S₈ and Co metal. The merits and demerits of each process of dissolution i.e., H₂SO₄/oxygen pressure leaching, atmospheric FeCl₃ leaching, NH₄OH/(NH₄)₂SO₄ pressure leaching are discussed in detail. Out of the three, the H₂SO₄/oxygen pressure leaching process is found to be the most suitable with more than 99% metal extraction efficiency within 1 h of leaching time. From the X-ray diffraction analysis, the different undissolved phases corresponding to different leaching processes have been identified. The metal extraction efficiency decreased in case of atmospheric FeCl₃ leaching and NH₄OH/(NH₄)₂SO₄ pressure leaching processes due to the formation of product layer such as elemental sulfur and goethite, respectively.