滑动弧等离子体处理酸性橙Ⅱ废水

采用气液两相滑动弧等离子体降解酸性橙Ⅱ,研究了酸性橙Ⅱ的降解动力学及降解机理。结果表明：当电压为10 kV,载气为O₂,气体流速为0.4 m³·h^-1,废水流量为20 ml·min^-1,电极间最窄处距离为3.5 mm,溶液浓度在300 mg·L^-1以下时,滑动弧等离子体对酸性橙Ⅱ的降解符合一级动力学规律。检测了纯水放电时H₂O₂、O₃生成量以及OH·的相对量。运用紫外光谱（UV-Vis）、离子色谱（IC）、色谱-质谱联用（GC-MS）等方法,测定出酸性橙Ⅱ的主要降解产物有乙酸、乙二酸、丙二酸、苯酚、3-羟基苯乙酮、萘、苯磺酸、邻苯二甲酸（酐）、β-萘酚等,并依此推测酸性橙Ⅱ的降解机理,即羟基自由基攻击酸性橙Ⅱ分子上与萘环相连的C—N键,导致C—N键的断裂,进而染料脱色矿化。     

臭氧强化电絮凝处理直接耐晒大红4BS模拟染料废水

采用臭氧强化电絮凝法处理直接耐晒大红4BS模拟染料废水,研究了染料脱色的影响因素及其COD_Cr去除动力学。考察了电流密度、溶液初始pH 值、染料初始浓度、支持电解质浓度、反应温度和臭氧流量对臭氧强化电絮凝法处理4BS染料脱色效率的影响。结果表明,电流密度15 mA·cm^-2,pH值10.0,4BS染料初始浓度100 mg·L^-1,支持电解质浓度3000 mg·L^-1,臭氧流量06 L·h^-1,20 ℃下反应50 min后4BS脱色率达94％以上。COD_Cr去除符合拟二级动力学。     

电絮凝处理甲基橙废水的实验及动力学模型

采用电絮凝法处理甲基橙模拟染料废水,研究了染料脱色的影响因素及其COD_Cr去除动力学。考察了静置时间、槽电压、极板间距、初始浓度、pH值以及电解质浓度对甲基橙染料脱色效率的影响。结果表明,槽电压为20 V,电流为0.4 A,极板间距为2.5 cm,废水体积为500 ml,甲基橙初始浓度为500 mg·L^-1,溶液pH值为3.0,电解质KCl的浓度为0.5 g·L^-1时,反应10 min后甲基橙脱色率可达97 %。根据电絮凝的絮凝沉淀理论和氧化反应机理,建立COD_Cr去除反应动力学模型,模型与实验数据拟合较好。通过模型参数的预测可以揭示甲基橙降解主要以絮凝沉淀为主,氧化降解为辅,同时溶液中二价铁Fe(II)的增加会影响COD_Cr去除率的下降。     

铌酸光催化降解甲基橙溶液

以铌酸为光催化剂,在高压汞灯照射下,对模拟染料废水甲基橙溶液进行光催化降解,研究过氧化氢加入量、催化剂用量和甲基橙起始浓度对光催化降解的影响。结果表明,当甲基橙起始浓度为15 mg·L^-1、30%过氧化氢用量为5.0 mL·L^-1和催化剂用量为1.5 g·L^-1时,光照1 h,甲基橙溶液降解率达到97％,在较低浓度下,甲基橙溶液的光催化降解反应符合一级动力学方程。     

曲霉对酸性黄染料的脱色研究

研究了曲霉菌丝球GY对酸性黄染料的脱色性能及对实际印染废水的脱色作用。菌球GY对染料的脱色需要一定的营养。甲醇对GY具有很好的解吸效果,其解吸率达93.6%,解吸后的菌球对染料仍有很好的脱色作用,其脱色率达94.4%,菌球可重复利用。     

丙酮酸分批发酵的供氧控制模式

以一株光滑球拟酵母的多重维生素营养缺陷型为研究菌株,考察了分批发酵中不同体积传氧系数(KL_a)对其产丙酮酸性能的影响.高KL_a(450 h^-1)下,丙酮酸产率较高(0.797 g·g^-1),但葡萄糖消耗速度较慢(1.14 g·L^-1·h^-1);低KL_a(200 h^-1)下,葡萄糖消耗速度快(1.97 g·L^-1·h^-1),然而丙酮酸产率(0.483 g·g^-1)却明显下降.根据发酵过程主要参数和碳流分配的变化特性提出了发酵前16h控制KL_a为450h^-1、16h后控制KL_a为200 h^-1的分阶段供氧控制模式,结果实现了高产量(69.4 g·L^-1)、高产率(0.636 g·g^-1)和高葡萄糖消耗速度(1.95g·L^-1·h^-1)的相对统一,丙酮酸生产强度(1.24g·L^-1·h^-1)比控制KL_a恒定为450、300和200h^-1的过程分别提高了36％、23％和31％.实验数据表明,供氧良好状态下细胞产丙酮酸性能出现的差异可能是由维生素处于亚适量水平时酵解产生的NADH去路不同,导致细胞处于不同的能量水平而引起的.     

定-转子反应器传热特性

采用蒸汽-水体系,在转子转速为400～1400 r·min^-1、水流量为0. 1～0. 5 m³·h^-1、蒸汽充足的实验条件下,研究了定-转子反应器(RSR)的传热特性,初步考察了操作参数对RSR液体分布的影响。实验结果表明：总传热系数随着转速的升高而增大,随着液量的增加而增大但增幅减小。小流量（0.1～0.3 m³·h^-1）与低转速（400 r·min^-1）时,温升不均,表明液体分布不均。最后采用因次分析法推导出定-转子反应器总传热系数关联式,且进行了统计检验,所得关联式与实验数据拟合较好。     

Fe3+掺杂介孔TiO2催化降解甲基橙

以表面活性剂十六烷基三甲基溴化铵醇溶液所形成的柱状胶束为模板剂,钛酸四丁酯为原料,经水解沉淀、晶化、沉降、抽滤、干燥及焙烧工艺制备出了介孔TiO₂固体催化剂。通过离子掺杂方法,用Fe(NO₃)₃溶液对介孔TiO₂掺杂,经搅拌、煮沸、晶化、蒸发、干燥及焙烧工艺,制备出了不同物质的量比的Fe³⁺/TiO₂催化剂。以甲基橙模拟染料废水,考察pH、催化剂用量、过氧化氢用量、催化剂Fe³⁺/TiO₂物质的量比和光照时间等因素对催化剂的催化性能的影响。结果表明,适量掺有Fe³⁺的催化剂Fe³⁺/TiO₂有利于太阳光催化甲基橙的效果,当甲基橙浓度为10 mg·L^-1、Fe³⁺与TiO₂物质的量比为0.000 5、催化剂用量为0.8 g·L^-1、过氧化氢为0.55 mol·L^-1、 pH=3并且太阳光直接照射20 min,脱色率达到96%。根据Languir-Hinshelwood动力学方程,近似推导出不同物质的量比Fe³⁺/TiO₂催化剂光催化降解甲基橙的动力学方程,并得出Fe³⁺与TiO₂物质的量比为0.000 5时的Fe³⁺/TiO₂催化剂,有最大宏观速率常数值,K₀为0.162 35 min^-1。     

负载型杂多酸催化剂的制备及光催化性能研究

采用浸渍法和微波法相结合,制备负载型杂多酸光催化剂H₃PMo₁₂O₄₀/TiO₂。在紫外光照射下,研究对模拟染料废水酸性蓝溶液的光催化降解的影响。结果表明,H₃PMo₁₂O₄₀/TiO₂比单独的H₃PMo₁₂O₄₀光催化性能好,〖JP2〗在初始浓度10 mg·L^-1酸性蓝溶液、m(H₃PMo₁₂O₄₀)∶m(TiO₂)=1∶3、催化剂加入量为90 mg·L^-1、pH=1.05、30%的H₂O₂用量10 mL·L^-1和180 min条件下,脱色率达93%以上。     

不锈钢基PbO2电极电催化氧化降解甲基橙性能的研究

本研究以自制的不锈钢基PbO2电极对25mg·L^-1的甲基橙溶液进行电催化氧化降解。考察了电流密度、支持电解质浓度、溶液pH值、温度等因素对甲基橙脱色率的影响,确定了电催化氧化甲基橙的最佳反应条件,即电流密度为50mA/cm^2,支持电解质Na2SO4的浓度为0．04mol·L^-1,降解20min后,甲基橙脱色率可达到90％以上。本研究还对几种不同印染废水进行了电催化氧化降解,结果表明,不锈钢基PbO2电极对不同的印染废水均有较好的脱色效果。     

转盘反应器固定根霉重复批次发酵生产脂肪酶

以聚氨酯海绵为载体将根霉固定于转盘表面,利用转盘反应器实现脂肪酶的固定化发酵。考察了通气量、转速、装液量及转盘个数等操作参数对发酵过程的影响,得到了优化的反应操作条件,即通气量4 L·min^-1,转速100 r·min^-1,装液量3.5L,采用三个转盘。在上述条件下进行重复批次实验,可重复5批次, 单位时间产率10931.1 U·h^-1, 是批次反应的3.5倍。固定化细胞连续发酵,大大缩短了发酵的时间, 酶的平均活力和时间产率获得大幅提高。     

OXIDATION OF C.I. ACID ORANGE 7 WITH OZONE AND HYDROGEN PEROXIDE IN A HOLLOW FIBER MEMBRANE REACTOR

The degradation of C.I. Acid Orange 7 by ozone combined with hydrogen peroxide was carried out in a hollow fiber membrane reactor, and batch recirculation mode of aqueous phase was employed. The effect of initial pH, hydroxyl radical scavenger, hydrogen peroxide concentration, liquid recirculation rate, gas flow rate, and gaseous ozone concentration on the decolorization of C.I. Acid Orange 7 was investigated. The results showed that the decolorization of C.I. Acid Orange 7 fits the pseudo-half-order kinetic model. The rate constant increased with the increase of initial pH, hydrogen peroxide concentration, liquid recirculation rate, gas flow rate, and gaseous ozone concentration. The presence of hydroxyl radical scavenger inhibited the decolorization rate by over 50%. The combination of ozone with hydrogen peroxide achieved a higher COD removal efficiency than ozone alone in the membrane reactor.     

米曲霉菌体的固定化及其稳定性

在液相培养基中将米曲霉菌体培养成直径为 1～ 2mm的菌球 ,以甲醛为交联剂、明胶为活性保护剂对其进行固定化研究 .在正交实验L₁₆(4⁵)的基础上 ,利用人工神经网络得到了较优的固定化条件 :菌体与固定液的用量比 (固液比 ) 1∶8,固定液中含明胶 5 g·L^-1、甲醛 5 g·L^-1,固定化时间为 1.5h .在此条件下制备的固定化米曲霉菌体比酶活为 15 0 0U ,比酶活保留率 83% .对固定化米曲霉菌体稳定性进行深入研究表明 ,其最适反应温度和 pH值分别为 6 3℃和 8.0 ,与游离菌体相比最适反应条件范围变宽 .在固定床反应器中用其连续拆分N -乙酰 -DL -丙氨酸 ,半衰期为 77天 ,具有较高的操作稳定性     

Decolorization of organic dyes by Irpex lacteus in a laboratory trickle‐bed biofilter using various mycelium supports

BACKGROUND: Dyes used in textile industries and released to their wastewaters are serious ecological problems as they are hard to degrade by common means used in wastewater treatment plants. White‐rot fungi can biodegrade textile dyestuffs using their extracellular enzyme system. However, it is difficult to keep them in functional form in conventional wastewater treatment systems, because of their specific nutritional and physiological requirements. Selection of a suitable bioreactor type and mode of operation are crucial for successful implementation of white rot fungi in waste water treatment processes. RESULTS: Both Remazol Brilliant Blue R (RBBR) and Reactive Orange 16 (RO16) were decolorized efficiently in the trickle‐bed reactor. A degree of decolorization exceeding 80% was achieved within 2 days with all mycelium carriers and both dyes. In reactors packed with plastic kitchen scourers and luffa sponge slices the decolorization degree reached 90% within 2 days. The initial rate of decolorization of RBBR dye was notably higher than the rate of RO16 decolorization. The lowest liquid hold‐up value (1–1.5%) was achieved in the reactor packed with the plastic kitchen scourers, the largest hold‐up value (3–5%) was observed in the reactor filled with luffa sponge. The longest mean retention time, 430 s, was achieved in the reactor with the luffa carrier at a liquid flow rate of 6.81 cm³ min^?1; the shortest mean retention times (10–20 s) were achieved in the reactor filled with the plastic kitchen scourers. Broad liquid residence time distributions were observed in tracer experiments at all volumetric flow rates. CONCLUSIONS: The ability of I. lacteus to secrete laccase and manganese peroxidase enzymes in a trickle‐bed bioreactor with three mycelium carriers was proved and quantified experimentally. The decolorization capability of the I. lacteus mycelium was only marginally influenced by the kind of carrier used. Basic operational characteristics of the reactor—residence times, axial dispersion and liquid hold‐up—were determined at various liquid flow rates. Copyright © 2009 Society of Chemical Industry     

Batch and continuous decolorisation of bleached kraft effluents by a white-rot fungus

The white-rot fungus Coriolus versicolor, used in the form of mycelial pellets, provided an effective means to decolorise lignin-containing kraft E₁-stage effluent from wood treatment processes. The mycelial pellets adsorbed the chromophores of the liquor and oxidised them in the presence of glucose. For an original liquor containing 7000 colour units (CU), the mean colour removal in batch experiments was estimated to be 300 CU g^?1 mycelium h^?1. The adsorption process and the oxidation process (following glucose addition) generally operated best at between pH 4 and 5, and at temperatures of 25 to 30°C, with a ratio of glucose to mycelium of 0.36, for a 24 h experiment. Magnesium ions accelerated the oxidation process. Decolorisation was then tested in a continuous reactor. The rate of loss of activity of the pellets was 1% per day and no mechanical damage to the pellets was observed in the reactor. With a liquor of 5600 CU a 50% decolorisation was attained in 15 to 30 h using 4.64 g dm^?3 mycelium. This represents a rate of chromophore consumption of 30 CU g^?1 mycelium h^?1.     

除油旋流器压降比的数学模型

实验研究了直径为 35mm的除油水力旋流器能量耗散与分流比的关系 .结果发现 ,当改变溢流孔径 (分别为 4、 6、 8mm)和入口流量 (分别为 30、 40、 5 0、 6 0、 70L·min^-1)时 ,只要分流比小于 2 5 % ,旋流器的能量耗散在不同入口流量下都能保持与入口流量对应的某一常数值 .当入口流量分别为 30、 40、 5 0、 6 0、 70L·min^-1时 ,旋流器的能量耗散大约分别为 10、 30、 80、 140、 2 0 5N·m·s^-1.根据旋流器的这一特征 ,并结合理论分析 ,建立了除油水力旋流器压降比数学模型 .该模型预测计算的压降比与分流比关系曲线与实验室测定的结果能很好地吻合     

Efficient decolorization of dye-containing wastewater using mycelial pellets formed of marine-derived Aspergillus niger

In order to improve the efficient decolorization of dye-containing water by biosorbent and understand the biosorption mechanism, the self-immobilization mycelial pellets were prepared using a marine-derived fungus Aspergillus niger ZJUBE-1, and an azo dye, Congo red was chosen as a model dye to investigate batch decolorization efficiency by pellets. The pellets as biosorbent showed strong salt and acid tolerance in biosorption process. The results for dye adsorption showed that the biosorption process fitted well with models of pseudo-second-order kinetic and Langmuir isotherm, with a maximum adsorption capacity of 263.2 mg·g~(-1) mycelium. During 6 batches of continuous decolorization operation, the mycelial pellets could possess efficient decolorization abilities(98.5%).The appearance of new peak in the UV–Vis spectral result indicated that the decolorization process may also contain biodegradation. The mechanism studies showed that efficient biosorption ability of pellets only relies on the active zone on the surface of the pellet, which can be enhanced by nutrition supplement or be shifted outward by a reculture process.     

蒽醌染料活性艳蓝KN-R的ACF电极成对电解脱色

在恒电流模式下,采用无隔膜电解槽,同时以活性炭纤维（ACF）为阳极和阴极,研究了不同电流密度下蒽醌染料活性艳蓝KN-R的脱色效果和脱色机制.结果表明：0～0.1 mA·cm^-2时,脱色是由于染料在ACF上的吸附,极化对吸附行为影响不大,脱色率在15%左右;0.2～0.6 mA·cm^-2时,阳极电位达到该染料在ACF上的氧化电位（0.5 V）,阴极电位未达到其还原电位（-0.7 V）,脱色是由于阳极电氧化和阴极吸附,脱色率最高可达52%;0.7～1.0 mA·cm^-2时,发生成对电解,即阳极电氧化和阴极电还原同时使染料脱色,脱色率最高可达83%.