泡沫分离技术在蛋白质多元体系分离中的应用

综述了泡沫分离蛋白质与糖,蛋白质与表面活性剂以及不同蛋白质的混合体系的研究进展,分析了泡沫分离技术在蛋白质分离中应用的前景并提出了需要解决的问题。     

糖-蛋白质混合体系泡沫分离过程研究

利用环流泡沫分离技术对若干糖 -蛋白质 (牛血清白蛋白 )混合模拟体系进行了分离实验 ,研究了 p H值对溶液表面张力和分离效果的影响 ,在综合考虑蛋白质泡沫夹带量、去除率、糖的损失率及分离因子的基础上 ,得到了泡沫分离的最优 p H值。研究结果表明 ,采用环流泡沫分离技术可以实现糖与蛋白质的分离 ,是生物多糖与蛋白质初级分离的一种有效方法     

消泡剂共存体系中泡沫分离蛋白质

在以牛血清白蛋白(BSA)为目标蛋白、聚环氧丙烷环氧乙烷甘油醚(PGE)为消泡剂的模拟体系中,考察了表面活性剂种类(非离子型Tween-20和离子型SDBS)、浓度、溶液pH及操作参数(气体流量、初始液池高度)对BSA分离效率的影响. 结果表明,2种活性剂均能改善模拟体系的泡沫性能,使泡沫分离. 后者作用更强并能促进BSA的吸附,因DBS-通过静电作用与带相反电荷的BSA结合形成疏水性更强的BSA-DBS复合物. pH通过影响BSA的电荷分布而影响其与SDBS的结合,进而影响对BSA的吸附,初始BSA浓度0.1 g/L, PGE 4 mg/L, SDBS 50 mg/L, pH为3.4时,约66%蛋白质浓缩在泡沫液中,富集比为5.34. 增加气速或初始液池高度可得到较高收率,但富集比减小.     

卧式加压溶气泡沫分离水溶液中低含量蛋白质

以大豆蛋白为目标蛋白,蛋白水溶液为模拟体系,采用卧式加压溶气泡沫分离装置考察了原料液流量、pH值、溶气水流量等因素对蛋白质脱除率的影响,并根据其分子结构特征从过程工程视角分析了以卧式泡沫分离装置由水中去除的优势.结果表明,最佳操作条件为:原料液浓度8mg/L,原料液流量50L/h,pH值4.5,溶气水流量275L/h,该条件下水中蛋白质的脱除率可达90.5%.     

泡沫精馏塔内泡沫液的传质模型

本文对泡沫精馏塔内泡沫的传质问题进行了分析，提出传质微分方程，得到了解析解，并用实验验证了解的正确性。     

泡沫分离方法回收钪

采用十二烷基聚氧乙烯琥珀酸单酯磺酸钠和十二烷基硫酸钠混合物作为表面活性剂,间歇式泡沫分离回收水溶液中的钪。讨论了料液pH值、表面活性剂浓度、鼓泡气流率、离子强度和操作时间等对分离效果的影响,得到了适宜的工艺条件。     

泡沫浮选萃取法分离精氨酸

以精氨酸水溶液为研究体系,采用十二烷基苯磺酸为起泡剂,以二(2-乙基已基)磷酸(P204)为萃取剂,对泡沫浮选萃取法分离提取水溶液中微量精氨酸的工艺进行了研究,考察了溶液中pH、鼓泡气体流量、表面活性剂浓度、萃取剂浓度的影响.结果表明在常温条件下,水相初始pH为7.0,萃取剂P204(稀释剂:正庚烷)体积分数为30%,水相和有机相的相比为17:1,十二烷基苯磺酸浓度为0.15 g/L,气体流量为200 mL/min时,溶液中精氨酸能达到满意的分离效果(富集比16.2,回收率97.2%).     

CONTINUOUS FOAM SEPARATION OF HEAVY METAL IONS FROM ELECTROPLATING INDUSTRIAL EFFLUENT

Process industries generate a large amount of waste materials during either production or downstreaming operations. Among many methods available for their separation, foam separation plays a major role, especially when the concentration of undesirable components involved is very low. The success of this technique depends on the stability and characteristics of the foam. This operation is simple with less maintenance as there are no moving parts. In the present study, simultaneous removal of metal ions such as chromium (VI), copper (II), and zinc (II) from electroplating industrial effluent was carried out with sodium lauryl sulfate (SLS) as surfactant in continuous foam column. Enrichment ratios of 3.94, 4.05, and 7.96 with a percentage removal of 59.0%, 63.0%, and 99.2% were obtained for chromium (VI), copper (II), and zinc (II) ions respectively at the optimum operating parameters of 23 cm liquid pool height in column, 0.1 liter per minute (Lpm) of airflow rate, feed flow rate of 4 liters per hour (Lph), 0.1% (w/v) of SLS concentration, pH of 6.0, and at feed concentrations of 32.5, 27.0, and 23.0 ppm for chromium (VI), copper (II), and zinc (II) ions respectively. Enrichment ratio was found to increase with an increase in feed flow rate. With a decrease in concentration of the bulk solution, the separation factor was found to increase. The study indicates the feasibility of continuous foam separation for treating industrial effluents.     

BUBBLE AND FOAM SEPARATION OF EMULSIFIED BITUMEN FROM TAR SAND WASTEWATER

Process waters generated by the steam purging of tar sand deposits in Vernal, Utah, were treated by means of second-stage foam separation and air flotation operations. Among the independent process variables considered were hydraulic detention time, air flowrate. temperature, and polymer or surfactant addition level. System performance evaluations were based on second-stage effluent levels of total organic carbon (TOC), chemical oxygen demand (COD), suspended solids (SS). total solids (TS), and turbidity. The results indicated that the most effective second-stage system studied was air flotation aided by polymer addition. Removals of TOC, COD, and SS accomplished by this system exceeded 98 percent.     

TREATMENT OF KRAFT PULP AND PAPER WASTEWATERS BY MEANS OF FOAM SEPARATION

The pulp and paper industry is the third largest industrial consumer of fresh water in the United States. The current use rate of over two trillion gallons annually is expected to increase as the demand for paper products continues to rise

Of the various methods of producing paper from wood, the Kraft process is the most widely used. Color, dissolved and suspended organic matter, and dissolved inorganic solids are major pollutants in Kraft processing wastewater. Current federal regulations limit the amount of solids and organic matter that a Kraft facility may dispose into public waters, so most plants have some form of wastewater treatment

In this study, the capacity of a continuous-flow, foam separation system to effect removals of color from a Kraft process wastewater was evaluated. The cationic surfactant, EHDABr, was used to precipitate color bodies in the wastewater and create a foam to carry the precipitates from the wastewater. The effect of pH adjustment was also considered. Color removals in the area of 90% were achieved

Removal of precipitated solids was enhanced by increasing the detention of wastewater in the treatment system.     

PREPARATIVE SEPARATION OF PROTEINS BY GRADIENT- AND STEPWISE-ELUTION CHROMATOGRAPHY: ZONE-SHARPENING EFFECT

A method is developed for predicting the zone-sharpening effect in linear gradient- and stepwise-elution chromatography of proteins. Numerical calculations have shown that the elution curve by different models are almost the same when the values of zone spreading parameters in the model are chosen so that the values of the number of the theoretical plates are equal. A good correlationship curve is established on the basis of the numerical calculations, from which the degree of the zone-sharpening can be easily predicted with a single dimensionless parameter.

When the modulator concentration is very high (the desorption is complete), the stepwise-elution chromatography can be regarded as the gradient elution with steep-slope of the gradient. The experimental stepwise elution cation-exchange chromatography of basic proteins from egg white has shown that the purity, the recovery and the concentration factor of the recovered fraction are very high.     

微晶泡沫玻璃与固体废弃物的循环利用

概述了微晶泡沫玻璃的制备工艺原理及流程,从结构方面讨论了微晶泡沫玻璃的性能及应用,介绍了废玻璃、粉煤灰、尾矿、冶炼渣、硼泥、煤矸石、陶瓷废料等固体废弃物在微晶泡沫玻璃中的应用。     

CONTINUOUS GAS SEPARATION WITH LIQUID IMPREGNATED PARTICLES IN GAS-SOLID REACTORS

The absorption of a gas in liquid filled porous particles in gas-solid reactors was studied both theoretically and experimentally. In the theoretical study a micro mode!, describing mass transport accompanied with reaction inside the particles, was implemented in the macro balance for several asymptotic operation modes. The theoretical study showed that the gas separation can be carried out very efficiently with the liquid filled porous particles, especially for the countercurrent mode of operation. The results of the simulations for the removal of H₂S from a gas stream also containing CO₂ showed that a very selective absorption process can be obtained. For these kind of selective absorption processes the simulations showed that the residence time of the particles is a crucial parameter

In the experimental part of this contribution the absorption of CO₂ in porous y-alumina particles filled with water or 2M aqueous solutions of tertiary - or primary alkanolamines was investigated. Experiments were carried out in a gas-solid reactor where the particles were falling down in an empty tube while gas was flowing co- or countercurrently. The conversion for the particles filled with water or the aqueous primary alkanolamine was predicted satisfactorily. For the particles filled with the tertiary alkanolamines, however, the experimental conversions were much higher than theoretically predicted. This difference probably must be attributed to an underestimation of the surface adsorption of CO₂ on the γ-alumina carrier which was very important for the slowly reacting tertiary alkanolamines     

利用煤粉炉渣制备微晶泡沫玻璃的研究

以煤粉炉渣为主要原料,以碳酸钙作为发泡剂,磷酸钠作为稳泡剂,再加入其他辅助原料制备了微晶泡沫玻璃,研究了碳酸钙和磷酸钠的掺入量、发泡温度、保温时间对微晶泡沫玻璃性能的影响,并且采用XRD分析其物相组成,结果表明,当发泡剂和稳泡剂的掺量分别为4.5%和5%,发泡温度为1000℃,发泡时间为20min时,试样已经完全转化为微晶泡沫玻璃,主晶相为硅灰石,次晶相为钙长石和辉石,平均泡径达2.03mm,表观密度为938 kg/m3,气孔率达52.6%,抗压强度达17.95MPa,抗弯强度达12.51 Mpa,热膨胀系数达5.67×10-6/℃,导热系数达0.20 W/(m.K)。     

SEPARATION OF URANIUM ON POLYURETHANE FOAM IMPREGNATED WITH TRIOCTYLPHOSPHINE OXIDE

ABSTRACT

A method is described for the quantitative separation of uranium from practically all other elements in 1M hydrochloric acid solution containing ascorbic acid. From such a solution uranium is retained selectively by a column containing open-cell polyurethane foam Impregnated with tri-n-octylphosphine oxide (TOPO). The uranium together with TOPO is eluted with ethanol and then 1t is adsorbed on a column of Dowex 1 anion exchange resin from a HC1-organic solvent system. Uranium is eluted with 1M hydrochloric acid.     

采用PUF废料制备环氧树脂固化剂

本文探讨了以二乙醇胺与乙二醇为解聚剂,聚氨酯微孔泡沫塑料（PUF）的解聚规律,并将解聚产物用作双酚A环氧树脂固化剂,得到了力学性能较好的固化产物。     

聚氨酯泡沫模板法低温制备SiC泡沫陶瓷

利用聚氨酯泡沫浸渍聚碳硅烷(PCS)与SiC微粉制成的有机溶剂浆料,挂浆素坯经热氧化处理后于1000℃下惰性气体中烧结制备SiC泡沫陶瓷。运用X衍射分析、扫描电镜、线收缩率测定和三点弯折强度测试等手段,研究了PCS含量、SiC颗粒粒径对泡沫陶瓷线收缩率、微观形貌、抗弯强度的影响。结果表明:PCS经1000℃热解产物为无定形结构,无定形SiC将SiC颗粒粘结起来,形成泡沫陶瓷的骨架筋结构,泡沫陶瓷孔径介于0.3～0.6mm之间;SiC泡沫陶瓷线收缩率随SiC颗粒尺寸与PCS含量的增大而增加,抗弯强度随颗粒尺寸的增加而减小;在颗粒尺寸为0.3μm时,PCS含量为10%时,抗弯强度最大为2.8MPa,当SiC颗粒尺寸为1μm、5μm、10μm和20μm时,PCS含量为15%时,其抗弯强度最大值分别为2.2 MPa、2.1MPa、1.8 MPa和1.4MPa。