Distribution and transformation behaviors of heavy metals during liquefaction process of sewage sludge in ethanol-water mixed solvents

Liquefaction of sewage sludge(SS)in ethanol-water cosolvents is a promising process for the preparation of bio-oil/biochar products.Effect of the combined use of ethanol and water on the distribution/transformation behaviors of heavy metals(HMs)contained in raw SS is a key issue on the safety and cleanness of above liquefaction process,which is explored in this study.The results show that pure ethanol facilitates the migration of HMs into biochar products.Pure water yields lower percentages of HMs in mobile/bioavailable speciation.Compared with sole solvent treatment,ethanol-water cosolvent causes a random/average effect on the distribution/transformation behaviors of HMs.After liquefaction of SS in pure water,the contamination degree of HMs is mitigated from high level(25.8(contamination factor))in raw SS to considerable grade(13.4)in biochar and the ecological risk is mitigated from moderate risk(164.5(risk index))to low risk(78.8).Liquefaction of SS in pure ethanol makes no difference to the pollution characteristics of HMs.The combined use of ethanol and water presents similar immobilization effects on HMs to pure water treatment.The contamination factor and risk index of HMs in biochars obtained in ethanol-water cosolvent treatment are 13.1-14.6(considerable grade)and 79.3-101.0(low risk),respectively.In order to further control the pollution of HMs,it is preferentially suggested to improve the liquefaction process of SS in ethanol-water mixed solvents by introducing conventional lignocellulosic/algal biomass,also known as co-liquefaction treatment.

Morphology Control of SrCO_3 Crystals using Complexons as Modifiers in the Ethanol-water mixtures

Using SrC12-6H2O and Na2CO3 as the main raw materials and adding different complexons as modifiers with simple co-precipitation method, SrCO3 crystals with distinct morphologies like spherical, bundle-like, overlapping plate-like, hexagonal star-like, dumbbell-like, etc. can be synthesized in the ethanol-water mixtures. The samples were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and Fourier transform infrared spectrograph （FT-IR）. The interrelated effect mechanism is presented in the end. Results show that the modifier carboxyl groups play a significant role in controlling the SrCO3 crystal morphologies, which can alter the crystal growth unit （Sr^2＋） supply mode and induce the crystal formation with the morphologies matching their spatial configurations.

Fluorescence spectrum characteristic of ethanol-water excimer and mechanism of resonance energy transfer

The steady-state fluorescence spectrum characteristic of ethanol-water excimer has been studied in this paper. By analysing the features of the sharp emission spectrum with fine structures in a shortwave band and the characteristics of the broad and featureless fluorescence peaks in the longwave band, one can conclude that the excimers are formed between the new ethanol-water cluster molecules in the excited state and the ground state through the interaction among different chromophores. The excitation spectra in the two fluorescence bands have been studied, and their emission mechanisms have been ascertained based on the energy transfer theory. Furthermore, the critical distance of the resonance energy transfer has been calculated.

Ethanol-Water Near-Azeotropic Mixture Dehydration by Compound Starch-Based Adsorbent

Ethanol-water near-azeotropic mixture dehydration was investigated by formulated compound starchbased adsorbent(CSA), which consists of corn, sweet potato and foaming agent. The net retention time and separation factor of water over ethanol were measured by inverse gas chromatography(IGC). Results indicated that water has a longer net retention time than ethanol and that low temperature is beneficial to this dehydration process. Orthogonal test was conducted under different vapor feed flow rates, bed temperatures and bed heights, to obtain optimal fixed-bed dehydration condition. Dynamic saturated adsorbance was also studied. It was found that CSA has the same water adsorption capacity(0.15 g/g)as some commercial molecular sieves. Besides, this biosorptive dehydration process was found to be the most energy-efficient compared with other ethanol purification processes.

Kinetic Study of Cementation of Copper on Zinc Metal in Ethanol-Water Mixtures

The cementation reaction of copper on zinc metal in solutions of different concentrations ofcopper sulphate, at 25℃, has been studied and it is found to be a first order reaction. Moreover,the rates of this reaction at 0.15 mol'L-1 copper sulphate solution have been measured in a varietyof ethanol-water media at temperatures from 20℃ to 40℃. The correlation between the masstransfer coefficient and the dielectric constant has been investigated. Also, the thermodynamicparameters of activation have been calculated. The isokinetic relationship reveals the existenceof compensation effect, where the solute-solvent interactions play an important role.

Identification of Best Model for Equilibrium Data of Ethanol-Water Mixture

Four empirical models are tested for fitting the T-y-x equilibrium data of ethanol-water mixture by minimizing the Root Mean Square （RMS） between equilibrium data and theoretical points. The total pressure of the correspondent data is 101.3 kPa. All models parameters are also identified. The study suggests that NRTL model fits the equilibrium data best with RMS = 0.4 %.

Design of Pilot Plant Packed Column for the Dehydration of Water from Ethanol-Water Mixtures

This use of biomass-based adsorbent has been explored for the column study of the adsorptive dehydration of water in ethanol-water mixtures. The column study was carried out using enzyme modified corn starch and the breakthrough curve parameters were used to design the packed bed column. The effect of flow rate on the breakthrough curves revealed that adsorption efficiency decreased with increased inflow rate. The empty bed contact time (τ) of the pilot plant packed column was 35.35 min while the breakthrough time is 40.78 min. 66.7% was the fraction of capacity left unused for the pilot plant from the design.

Molecular dynamics simulation of the interaction of ethanol-water mixture with a Pt surface

An analysis of the molecular dynamics of ethanol solvated by water molecules in the absence and presence of a Pt surface has been performed using DL_POLY_2.19 code. The structure and diffusion properties of an ethanol–water system have been studied at various temperatures from 250 to 600 K. We have measured the self-diffusion coefficients of the 50:50% ethanol–water solution;in the absence of a Pt surface our results show an excellent agreement–within an error of 7.4% – with the experimental data. An increase in the self-diffusion coefficients with the inclusion of a Pt surface has been observed. The estimation of the diffusion coefficients of both water and ethanol in the presence of a Pt surface shows that they obey the Arrhenius equation;the calculated activation energies of diffusion of ethanol and water are 2.47 and 2.98 Kcal/mole, respectively. The radial distribution function graphs and density profiles have been built;their correlations with the self-diffusion coefficients of both ethanol and water molecules are also illustrated.

Interaction mechanism of collagen peptides with four phenolic compounds in the ethanol-water solution

This study demonstrated the interaction mechanism of collagen peptides(CPs)with 4-ethylphenol(4-EP),phenol,guaiacol,and 4-ethylguaiacol(4-EG)in the ethanol-water solution.The ultraviolet visible spectroscopy,zeta potential tests and hydrogen nuclear magnetic spectroscopy manifested that CPs interacted with the phenolic compounds.Meanwhile,Isothermal titration calorimetry determination indicated that the CPs was hydrogen bonded with 4-EP in 52%(v/v)ethanol-water solution,while the hydrophobic forces played a major role in the interaction of CPs with guaiacol and 4-EG,respectively.Moreover,hydrogen and hydrophobic bonds were involved in the interaction between CPs and phenol.Finally,Head Space-solid Phase Microextraction Gas Chromatography Mass Spectrometry analysis indicated that the content of phenolic compounds in model solution efficiently decreased with the presence of CPs.In the real liquor,it was found that the content of volatile compounds(including phenolic compounds)was obviously decreased after CPs added.

表面活性剂对含盐双流体细水雾灭火效能的影响

为探究不同类型表面活性剂对含盐双流体细水雾灭火效能的影响,选用十二烷基苯磺酸钠(SDBS)、椰油酰胺丙基甜菜碱(CAB35)、烷基糖苷(APG0810),从灭火时间、冷却效果、CO浓度峰值三方面开展表面活性剂对含盐双流体细水雾灭火效能影响研究。结果显示:在空气环境下,3种表面活性剂可以有效缩短含盐类添加剂细水雾灭火时间,从而降低其灭火过程中的CO浓度峰值,但同时由于其液滴粒径减小,容易受到湍流影响,导致其冷却效果相比含单一盐类添加剂细水雾有所降低。在CO_(2)环境下,由于CO_(2)比定压热容较小,表面活性剂在对含单一盐类添加剂细水雾改性后分别存在灭火时间微幅缩短和灭火时间延长的实验现象,并且相比含单一盐类添加剂细水雾,其灭火过程中的CO浓度峰值有所增大,冷却效果也有所降低。研究结果将为防治醇基燃料火灾提供参考。

糖醋酒液诱捕核桃园小黄鳃金龟的效果

为研究核桃园中小黄鳃金龟Pseudosymmachia flavescens(Brenske)成虫的发生规律,探讨糖醋酒液对小黄鳃金龟的诱捕效果,本研究采用正交试验筛选糖醋酒液最佳配方,并于2020年-2022年在陕西省商洛市镇安县核桃园开展不同配方糖醋酒液及诱捕器悬挂不同高度诱捕小黄鳃金龟成虫试验。结果表明,糖∶乙酸∶乙醇∶水为3 g∶4 mL∶3 mL∶20 mL的配方对小黄鳃金龟成虫诱捕效果最佳。商洛市镇安县核桃园小黄鳃金龟成虫的发生期为5月上旬至9月中旬,盛发期为6月中旬至7月中旬。糖醋酒液诱捕器在距地面0.5~1.5 m范围内诱捕量随高度升高增加,当高度升至2.0 m时诱捕量明显下降,悬挂高度1.5 m时诱捕量570头/年、占比50.04%,显著高于其他高度处理。糖醋酒液3∶4∶3∶20配方(m∶V∶V∶V)既可准确监测核桃园小黄鳃金龟成虫种群发生动态,亦可高效诱杀用于防治。

水相循环对乙醇-水体系液化蜈蚣草产油特性和砷富集影响

砷富集植物的生态友好处置是实现植物修复产业化发展的关键环节,对土壤重金属污染治理高质量发展起到了制约作用。该研究以蜈蚣草为原料,采用乙醇-水作为反应共溶剂体系,考察了乙醇占比和水相循环次数对蜈蚣草水热产油及重金属砷分布的影响。研究结果显示:在乙醇浓度60%、水相循环3次的条件下,蜈蚣草液化生物油产率最高可达51.08%,其热值为29.15 MJ/kg。生物油主要由酯(>80%)、酚、醇、酮、烃等组成。随水相循环次数的增加,生物油中的酯类和酚类物质增加,高沸点化合物会减少,生物油产率和能量回收率分别提高了58%和32.23%;经过水相循环液化后,超过80%的重金属砷主要分布在水相,且砷的浓度增加至215.05 mg/kg,该结果可为砷富集植物无害化后处置提供参考。因此,水相循环利用是砷富集植物液化处置制取高产率生物油与砷富集的有效途径,为富集植物生态友好处置提供了新的思路。

渗透汽化膜过程乙醇水蒸气真空分馏热质传递

对透醇选择性渗透汽化膜下游的渗透蒸气进行分级冷凝,重点研究了真空冷凝分馏器的热-质传递行为,分析了进口渗透蒸气流速对真空冷凝分馏器传热系数与冷凝行为的影响.进口蒸气流速从3.09 m/s提高至8.05 m/s时,总传热系数由37.06 W/(m^(2)·K)提高至145.27 W/(m^(2)·K),渗透蒸气侧冷凝给热系数也由55.81 W/(m^(2)·K)提高至544.60 W/(m^(2)·K).不同流速下,传热过程各步骤热阻占比不同,3.09 m/s时,渗透蒸气侧热阻占比较大,高达82.99%;流速提高至8.05 m/s后,冷却介质侧热阻占比增大,达到65.66%.随进口蒸气流速的提高,真空冷凝分馏器中蒸气冷凝量在总渗透蒸气中的占比由41.82%提高至68.19%,乙醇质量分数由3.45%提高到10.66%.

不同灵芝菌丝体水提物对乙醇诱导LO2肝细胞损伤的保护作用

为了探讨不同灵芝菌丝体水提物对乙醇诱导LO2肝细胞损伤的保护作用,本文分析了7种不同灵芝菌株发酵菌丝体水提物对乙醇诱导LO2细胞损伤的保护作用。利用乙醇诱导LO2细胞建立体外肝损伤模型,并以细胞存活率、谷丙转氨酶(Alanine Aminotransferase,ALT)、谷草转氨酶(Aspartate Aminotransferase,AST)、活性氧(Reactive Oxygen Species,ROS)、超氧化物歧化酶(Superoxide dismutase,SOD)、谷胱甘肽(Glutathione,GSH)和丙二醛(Malondiadehyde,MDA)水平为指标考察灵芝菌丝体水提物对乙醇诱导LO2细胞损伤的保护效果。结果表明,7种灵芝菌株的菌丝体水提物均具有不同程度的保护作用。综合比较,G0119与G0154菌丝体的水提物作用效果较优,相较模型组,LO2细胞存活率显著提高(P<0.05),细胞培养液中的ALT、AST活力显著降低(P<0.05),细胞内ROS水平显著降低(P<0.05),SOD活力、GSH含量显著升高(P<0.05),MDA含量显著降低(P<0.05)。经相关性分析,发现水提物中多糖组分2的分子量大小与其保肝活性呈正相关,即分子量越大,活性越强。综上,灵芝菌丝体水提物对乙醇诱导的体外肝损伤起到保护作用,并且G0119与G0154菌株的作用效果较优,其保肝作用与提取物中多糖组分的分子量大小相关。

气相色谱法测定花露水中乙醇含量

含有乙醇的化妆品,会刺激人体皮肤。而花露水中乙醇含量高达70%~75%。本研究依据《化妆品安全技术规范》指导原则,建立了花露水中乙醇含量测定方法,详实地对该方法学进行考察,并对不同品牌花露水中乙醇含量进行测定。结果表明,该方法专属性好,准确性高、稳定性好、重复性好;线性范围为0.5%~12%,线性方程为y=209.68x-66.147(R=0.9994),检测限为0.005%,回收率为97.39%~100.08%。该方法为科学测定花露水中乙醇含量提供理论依据,也为消费者权益的维护提供了科学保障。

白果仁35%乙醇-水洗脱部位多糖及多肽的含量测定

目的对白果仁止咳有效部位35%乙醇-水洗脱部位中多糖及多肽的含量进行测定,为白果仁的综合开发和质量控制提供科学依据。方法采用苯酚-硫酸法、双缩脲法,建立标准曲线,并进行精密度、稳定性、重复性、加样回收率的考察。结果白果仁35%乙醇-水洗脱部位中多糖和多肽均在浓度范围内有良好的线性关系,方法学验证RSD值均小于2%,加样回收率分别为97.96%、97.94%,多糖含量为13.99%,多肽含量为31.41%。结论本研究建立的白果仁35%乙醇-水洗脱部位多糖和多肽含量测定方法简单可行,稳定性和重现性好。

西伯利亚接骨木环烯醚萜苷和木脂素组分提取分离的初步研究

目的西伯利亚接骨木环烯醚萜苷和木脂素组分的提取分离,同时建立接骨木中莫诺苷和总木脂素的含量测定方法。方法采用乙醇醇提取、大孔树脂吸附得到接骨木有效组分,通过HPLC测定接骨木中莫诺苷的含量以及采用紫外分光光度法测定接骨木中总木脂素的含量。结果接骨木中富含环烯醚萜苷类、木脂素类以及三萜类成分的有效组分,接骨木提取物和30%乙醇洗脱部位中标识性成分莫诺苷含量分别为0.254%和2.63%;50%洗脱部位的总木脂素含量为38.07%。结论通过HPLC和紫外分光光度法测定接骨木中有效组分的含量,以期为接骨木的开发利用提供一定的科学依据。

枳椇子不同溶剂提取物对黄嘌呤氧化酶的作用及动力学研究

目的:探讨不同溶剂提取枳椇子对黄嘌呤氧化酶(XOD)的影响及其动力学模型,为研究高尿酸血症提供实验依据。方法:用水、50%乙醇、70%乙醇、95%乙醇提取枳椇子,测定各提取液中黄酮类成分的含量,采用紫外分光光度法分析不同溶剂提取液对XOD的作用及动力学模型。结果:枳椇子不同溶剂提取液对XOD均有抑制作用,其中50%乙醇提取液和70%乙醇提取液的抑制作用较强,其提取液中黄酮类成分含量也较高,抑制效果呈剂量依赖性;95%乙醇提取物黄酮总量较低,但也显示出较好的抑制作用。动力学分析显示,不同溶剂提取液对XOD的亲和力值α均大于1,70%乙醇提取液对XOD的亲和力值为134.40,更易与XOD结合,各提取液均表现为混合型抑制。结论:枳椇子提取液具有抑制XOD的作用,效果以50%乙醇提取液和70%乙醇提取液为著,95%乙醇提取物对XOD的抑制效果与提取液中的其他成分相关。枳椇子提取液的抑制作用类型属于混合型抑制,即竞争性-非竞争性抑制,且竞争性抑制占主导地位。

分子动力学模拟研究水/乙醇二元体系的热力学性质

采用分子动力学模拟方法研究了常温常压下水/乙醇体系的热力学性质,得到了不同浓度下二元体系的密度、自扩散系数、超额摩尔体积和径向分布函数。结果表明:随着乙醇摩尔分数的增加,二元体系的密度呈递减趋势,超额摩尔体积则先减小后增大且存在最小值,而乙醇的自扩散系数增大;结合径向分布函数分析可知,在乙醇低浓度时,水分子间的氢键网络结构较强,乙醇分子分散于其中,而随着乙醇浓度的增加,乙醇-乙醇分子之间的关联性增强,形成自己的氢键网络,而水分子仍倾向于自聚集,两种氢键网络相互交错。

基于水自由基阳离子快速检测甲醇和乙醇

本文采用常压电晕放电电离质谱技术,开发了一种快速检测甲醇和乙醇含量的方法。基于水自由基阳离子分别与甲醇和乙醇相互作用形成相应的水自由基阳离子复合物[CH_(3)OH+H_(2)O]^(+·)(m/z 50)和[CH_(3)CH_(2)OH+H_(2)O]^(+·)(m/z 64),实现了不同种类酒精饮料中甲醇和乙醇的直接快速定性与定量分析。结果表明,甲醇和乙醇的检出限分别为0.011、0.004 mg/L,定量限分别为0.038、0.014 mg/L。该方法无需样品前处理、操作简单、分析速度快,适合含水体系的检测,对复杂体系中甲醇和乙醇的定量分析具有指导意义。