制霉菌素溶解性能研究

制霉菌素难溶于水，使用上受一定的限制。我们利用二甲亚砜做溶剂，测定了制霉菌素的最大溶解量。绘制了制霉菌素二甲亚砜、无水乙醇、水的助溶相图。研究了制霉菌素二甲亚砜、无水乙醇、水复合溶剂的配比及稀释条件。     

两性霉素和制霉菌素发酵及添加其发酵液对甘油发酵影响的比较

研究了两性霉素和制霉菌素的发酵过程,比较了添加两性霉素和制霉菌素发酵液对克鲁氏假丝酵母发酵甘油的影响,结果表明两性霉素发酵菌体与制霉菌素发酵菌体的生长过程类似,都存在一个最大值;当两性霉素和制霉菌素发酵至156h和144h时,菌体分别达到最大,但制霉菌素发酵的菌体高于两性霉素发酵的菌体;当两性霉素和制霉菌素发酵至192h时,发酵液中两性霉素和制霉菌素的质量浓度分别达到148μg/mL和181μg/mL。与不添加两性霉素和制霉菌素发酵液的甘油发酵相比,添加两性霉素和制霉菌素发酵液可进一步提高甘油的含量,其甘油质量分数分别增加了0.57%和2.0%;此外,添加制霉菌素发酵液的菌体和甘油含量要高于添加两性霉素发酵液的菌体和甘油含量,而残糖较低,而且添加制霉菌素发酵液的甘油含量比添加两性霉素发酵液的甘油质量分数增加了1.47%。     

含酚废水萃取脱酚技术研究进展

论述了目前主要应用的萃取脱酚技术,包括传统的液-液萃取、络合萃取、液膜萃取、超临界萃取;分析了萃取脱酚过程的主要影响因素,包括萃取剂的选择、萃取pH、萃取温度、萃取相比,介绍了近年来常用的萃取脱酚设备,对未来萃取脱酚技术研究的主要方向提出了建议。     

超声强化超临界流体萃取海藻脱氢乙酸的研究

研究了超声强化超临界流体萃取海藻DHA技术,研究了萃取温度、萃取压力、流体流量以及萃取时间的影响.结果表明超声强化超临界流体萃取可以降低萃取温度、萃取压力以及超临界流体的流量,还可缩短萃取时间,提高萃取率.     

超声强化超临界流体萃取薏苡仁油和薏苡仁酯的影响因素及效果

考察了超声强化超临界流体萃取(USFE)薏苡仁中的薏苡仁油和薏苡仁酯的效果。以 CO2作为超临界流体分别研究了萃取过程中萃取温度、萃取压力、原料颗粒大小、超临界流体流量、超声参数、萃取时间等因素对萃取率的影响,并与超临界流体萃取(SFE)进行对比。结果表明,超声强化超临界流体萃取过程,最适宜的萃取温度为 40℃,比超临界流体萃取的最适宜的萃取温度降低了 5℃;最适宜的萃取压力为 20Mpa, 比超临界流体萃取的最适宜的萃取压力降低了 5Mpa;最佳萃取时间为 3.5h,比超临界流体萃取的最佳萃取时间缩短了 0.5h;萃取率提高约 10%左右。若萃取率相同时,流体流量可减少 0.5L·h-1 ,原料粒径的要求可放宽。     

甲基丙烯酸萃取分离模拟研究

本文利用模拟计算对甲基丙烯酸萃取的烃类、酯类和混合烃酯类萃取剂进行了系统的研究。通过对比了不同萃取剂对甲基丙烯酸的萃取效果剂、萃取剂回收率及萃取相中水的含量确定了最优的萃取剂。对于烃类萃取剂来说,环己烷、己烷和邻二甲苯为最优萃取剂,而酯类萃取中优选丙酸乙酯、丙酸丙酯和丙烯酸乙酯。最后将优选的烃类和酯类萃取剂作为混合萃取剂应用到甲基丙烯酸萃取模拟计算中,发现烃类的加入不仅可以降低萃取效果,而且还可以降低萃取相中的水的含量,为工业中甲基丙烯酸的萃取提供指导意义。     

酚类环境雌激素的样品前处理技术研究进展

酚类环境雌激素是最为常见的环境雌激素之一,其对人类、环境和生态的影响受到世界范围的关注。介绍了酚类环境雌激素的种类和毒性,详细讨论了各种样品前处理技术,包括溶剂萃取、索氏提取、固相萃取、基质固相分散萃取、微波辅助萃取、加速溶剂萃取、膜萃取、固相微萃取、搅拌棒吸附萃取、分子印迹聚合物萃取、超声辅助萃取、离子液体萃取、浊点萃取、超临界流体萃取等,并对酚类环境雌激素的样品前处理技术进行了总结和展望。     

Research Progress of Sample Pretreatment of Phenolic Environmental Estrogens

酚类环境雌激素是最为常见的环境雌激素之一,其对人类、环境和生态的影响受到世界范围的关注.介绍了酚类环境雌激素的种类和毒性,详细讨论了各种样品前处理技术,包括溶剂萃取、索氏提取、固相萃取、基质固相分散萃取、微波辅助萃取、加速溶剂萃取、膜萃取、固相微萃取、搅拌棒吸附萃取、分子印迹聚合物萃取、超声辅助萃取、离子液体萃取、浊点萃取、超临界流体萃取等,并对酚类环境雌激素的样品前处理技术进行了总结和展望.     

超临界CO_2萃取大豆磷脂的影响因素研究

应用超临界CO2 萃取技术从大豆粗磷脂中提纯得到了质量分数为 98%的大豆磷脂。研究了萃取压力、萃取温度、萃取时间对萃取率的影响 ,3个影响因素的影响顺序为 :萃取温度 >萃取时间 >萃取压力。优化工艺条件是 :萃取压力 2 0MPa ,萃取温度 5 0℃ ,萃取时间 5h。     

甲基丙烯酸水溶液萃取分离研究

以氧化叔丁醇或异丁烯合成甲基丙烯酸所产生的水溶液需要进行萃取分离。本文通过实验测定了各种溶剂的萃取率,研究了不同萃取温度的影响,考察了分别以水溶液和萃取剂为连续相的萃取效率,分析了萃取絮状物的产生原因,确定了萃取溶剂、温度和连续相等萃取工艺条件。     

伊利石负载壳聚糖去除水中酸性大红3R的研究

以伊利石为原料制稀伊利石负载壳聚糖吸附剂,研究了吸附剂对酸性大红3R的吸附性能。考察了溶液pH值、吸附剂用量、吸附剂粒径、吸附时间对吸附的影响。结果表叫,壳聚糖负载量为0．6g,pU值为4,吸附剂用量为0．2g时,对酸性大红3R的吸附效果较好。吸附平衡时间为60min,饱和吸附,量为138．2mg·g^-1。     

活性炭吸附法处理乙烯废碱液的研究

以活性炭为吸附剂处理乙烯废碱液,通过单因素实验,考查了吸附时间、吸附温度、活性炭粒度、活性炭投加量、废碱液pH对硫去除率的影响。吸附法处理乙烯废碱液的最佳工艺条件:吸附时间50 min、吸附温度25℃、活性炭粒度20~40目、活性炭投加量1.8 g、乙烯废碱液pH为3。在此条件下可使20 mL乙烯废碱液中硫浓度由1113.25 mg/L降到1.98 mg/L,硫去除率达99.82%,COD浓度由800000 mg/L降到5600 mg/L,COD去除率达99.9%。     

磺化腐植酸对Ni(Ⅱ)吸附性能的热力学及动力学研究

通过磺化腐植酸对重金属Ni(Ⅱ)吸附性能的实验,研究了吸附过程中的吸附等温线,探讨了吸附热力学特征和吸附动力学模型。结果表明:在室温条件下(20~25℃),pH为5~6,吸附平衡时间120 min,磺化腐植酸对Ni(Ⅱ)吸附类型符合Freundlich吸附模型,吸附过程可用Ho准二级反应动力学模型描述。     

α-MnO_2纳米线吸附染料废水的动力学研究

通过水热一步合成了α-MnO2纳米线,采用静态吸附法研究吸附剂的用量、吸附时间对α-MnO2吸附刚果红的影响,且随吸附剂含量的增大,平衡吸附量减小,到达平衡的时间短。     

改性硅藻土处理乙烯碱性废液的研究

本研究采用改性硅藻土处理乙烯废碱液,通过单因素实验,考察了改性硅藻土处理乙烯废碱液的吸附温度、吸附时间、改性硅藻土加入量和乙烯废碱液的pH对乙烯废碱液中硫去除率的影响,确定了改性硅藻土处理乙烯废碱液的最佳工艺条件。实验结果表明,其最佳工艺条件:吸附时间为40 min、吸附温度为20℃、改性硅藻土加入量为1.5 g、乙烯废碱液的pH为3。在此条件下,乙烯废碱液中硫浓度由560.4 mg/L降到29.4 mg/L,硫去除率达94.75%;乙烯废碱液的COD由148000 mg/L降到12000 mg/L,COD去除率达91.89%,改性硅藻土在乙烯废碱液处理方面具有很好的应用前景。     

NaHCO处理胶乳生产污泥制备吸附剂对阳离子染料的吸附

以胶乳生产厂脱水污泥为原料、1.40mol/L的NaHCO₃作膨胀剂,60℃浸渍并超声处理30min,污泥烘干后再经高温炭化制备吸附剂,将其用于吸附阳离子兰X-GRRL染料溶液,考察炭化温度、炭化时间、吸附剂粒径、吸附剂投加量、吸附时间及溶液pH对吸附效果的影响,并对其吸附动力学和吸附等温线类型进行了探讨。结果表明：污泥在炭化温度700℃、炭化时间120min的条件下,制备的吸附剂（粒径<0.75mm）的比表面积为118.95m²/g,孔隙结构较为发达,对染料溶液吸附效果最佳;在振荡频率150r/min、吸附温度为25℃±0.10℃、初始染料质量浓度为250mg/L、吸附剂投加量为1.20g/L、溶液pH为5.47、吸附时间为300min时,溶液脱色率可达98.30%,染料吸附量为204.80mg/g;其吸附动力学可用准二级动力学方程进行描述;符合Langmuir型吸附等温线,属于单分子层吸附;吸附剂浸出液及吸附处理后的染料溶液的COD值分别为4.00mg/L和20.00mg/L,不会对水体造成二次污染。     

Adsorption behavior of Cd(II) ions on humic acid-immobilized sodium alginate and hydroxyl ethyl cellulose blending porous composite membrane adsorbent

A novel porous composite adsorbent was prepared by using sodium alginate and hydroxyl ethyl cellulose blending as an immobilization matrix for humic acid, then crosslinked by glutaraldehyde. The adsorbent was prepared using polyethylene glycol (PEG) as porogen and used to remove Cd(II) ions from aqueous solution. The physico-chemistry properties of adsorbent before and after adsorption were investigated by FT-IR, SEM and EDX methods. Batch adsorption experiments were carried out to investigate the effects of the amount of PEG adding to the adsorbent, solution pH, dosage of adsorbent, initial Cd(II) ions concentration and contact time. The prepared adsorbent exhibited the maximum uptake of 148.9 mg/g under the optimal adsorption condition. Kinetics experiments indicated that the pseudo-first-order model displayed the best correlation with adsorption kinetics data. The Crank model showed that the intraparticle solute diffusion was the rate-controlling adsorption step. Besides, experimental data could be better described by the Freundlich isotherm model. Dubinin–Radushkevich isotherm indicated that the adsorption was mainly an ion exchange process. The results suggested that the prepared adsorbent is promising for using as an effective and economical adsorbent for Cd(II) ions removal.     

Low cost adsorbents obtained from ash for copper removal

We investigated the utilization of ash and modified ash as a low-cost adsorbent to remove copper ions from aqueous solutions such as wastewater. Batch experiments were conducted to determine the factors affecting adsorption of copper. The influence of pH, adsorbent dose, initial Cu²⁺ concentration, type of adsorbent and contact time on the adsorption capacity of Cu²⁺ from aqueous solution by the batch adsorption technique using ash and modified ash as a low-cost adsorbent were investigated. The optimum pH required for maximum adsorption was found to be 5. The results from the sorption process showed that the maximum adsorption rate was obtained at 300 mg/L when a different dosage of fly ash was added into the solution, and it can be concluded that decreasing the initial concentration of copper ion is beneficial to the adsorption capacity of the adsorbent. With the increase of pH value, the removal rate increased. When the pH was 5, the removal rate reached the maximum of over 99%. When initial copper content was 300 mg/L and the pH value was 5, the adsorption capacity of the zeolite Z 4 sample reached 27.904 mg/g. The main removal mechanisms were assumed to be the adsorption at the surface of the fly ash together with the precipitation from the solution. The adsorption equilibrium was achieved at pH 5 between 1 and 4 hours in function of type of adsorbent. A dose of 1: 25 g/mL of adsorbent was sufficient for the optimum removal of copper ions. For all synthesized adsorbents the predominant mechanism can be described by pseudo-second order kinetics.     

浓碱溶液中氯化钠的吸附分离

用自制的新型吸附剂从浓氢氧化钠溶液中吸附分离氯化钠,确定了吸附时间、碱液浓度、吸附剂用量、吸附温度等因素对吸附的影响.结果表明,该吸附剂对浓碱溶液中的氯化钠有良好的吸附分离效果,且容易洗脱,重复使用10次以上仍具有较好的吸附性能.     

Adsorption behavior of fluoride ions using a titanium hydroxide-derived adsorbent

The removal behavior of fluoride ions was examined in aqueous sodium fluoride solutions using a titanium hydroxide-derived adsorbent. The adsorbent was prepared from titanium oxysulfate (TiOSO₄·xH₂O) solution, and was characterized by X-ray diffraction, scanning electron microscopy, thermogravimetry-differential thermal analysis, Fourier transform infrared spectrum and specific surface area. Batchwise adsorption test of prepared adsorbent was carried out in aqueous sodium fluoride solutions and real wastewater containing fluoride ion. The absorbent was the amorphous material, which had different morphology to the raw material, titanium oxysulfate, and the specific surface area of the adsorbent (96.8 m²/g) was 200 times higher than that of raw material (0.5 m²/g). Adsorption of fluoride on the adsorbent was saturated within 30 min in the solution with 200 mg/L of fluoride ions, together with increasing pH of the solution, due to ion exchange between fluoride ions in the solution and hydroxide ions in the adsorbent. Fluoride ions were adsorbed even in at a low fluoride concentration of 5 mg/L; and were selectively adsorbed in the solution containing a high concentration of chloride, nitrate and sulfate ions. The adsorbent can remove fluoride below permitted level (< 0.8 mg/L) from real wastewaters containing various substances. The maximum adsorption of fluoride on the adsorbent could be obtained in the solution at about pH 3. After fluoride adsorption, fluoride ions were easily desorbed using a high pH solution, completely regenerating for further removal process at acidic pH. The capacity for fluoride ion adsorption was almost unchanged three times after repeat adsorption and desorption. The equilibrium adsorption capacity of the adsorbent used for fluoride ion at pH 3 was measured, extrapolated using Langmuir and Freundlich isotherm models, and experimental data are found to fit Freundlich than Langmuir. The prepared adsorbent is expected to be a new inorganic ion exchanger for the removal and recovery of fluoride ions from wastewater.