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941.
对H2O2/Fe(II)处理山梨醇生产废水进行了研究。考察了过氧化氢的投加量、pH值、反应时间等对处理效率的影响。通过试验确定了废水处理的最佳条件:过氧化氢(30%)投加量为0.12mL,硫酸亚铁投加量为0.18g,pH值为3.2,处理时间为40min,温度为35℃,硫酸镁投加量为1.0g,此时CODcr去除率为81.19%。试验结果表明此法处理山梨醇生产废水,不但降低了CODcr,对氧化反应后剩余的铁离子去除效率也比较高。 相似文献
942.
分光光度法快速测定水中苯酚 总被引:2,自引:1,他引:1
建立了简单、快速的测定水中苯酚的分光光度法。方法基于苯酚与硝普钠在有氨基的试剂盐酸羟胺存在下发生Berthelot颜色反应,生成靛酚染料,从而对苯酚进行光谱测定。考察了测定波长,pH值、Na2HP04-NaOH缓冲溶液用量,硝普钠的用量、盐酸羟胺的用量,反应时间对苯酚检测的影响。在优化的实验条件下,线性范围为0.05—0.5mg·L^-1(r=0.9996)。检出限为0.005mg·L^-1,对浓度为0.3mg·L^-1的苯酚样品溶液平行测定5次,RSD为1.32%。以上结果表明,此方法具有线性范围较宽,灵敏度和精密度较高,操作简便,易实现水质在线监测等特点。 相似文献
943.
CUI Huxiong CHENG Tiantao YU Xingn CHEN Jianmin XU Yongfu FANG Wen 《环境科学学报(英文版)》2009,21(8):1103-1107
The variations of sulfate formation and optical coe cients during SO2 heterogeneous reactions on hematite surface under di erent
SO2 concentrations were examined using in situ di use reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion
chromatograph (IC). Laboratory experiments revealed that within ambient SO2 of 0.51–18.6 ppmv, sulfate product, producing velocity,
absorption and backward scattering coe cients showed an increasing trend with SO2 concentration. Under given SO2 concentration,
the velocity of sulfate producing performed an evolution of initial increasing, midterm decreasing and final stabilizing. The reactive
uptake and Brunauer-Emmett-Teller (BET) uptake coe cients of heterogeneous reactions rose with SO2 and exhibited high reactivities.
Considering global warming, this result is important for the knowledge of heterogeneous reactions of SO2 on mineral particle surface
in the atmosphere and the assessment of their impacts on radiative forcing. 相似文献
944.
Nitrogen removal via nitrite from municipal landfill leachate 总被引:2,自引:0,他引:2
A system consisting of a two-stage up-flow anaerobic sludge blanket (UASB), an anoxic/aerobic (A/O) reactor and a sequencing
batch reactor (SBR), was used to treat landfill leachate. During operation, denitrification and methanogenesis took place simultaneously
in the first stage UASB, and the e uent chemical oxygen demand (COD) was further removed in the second stage UASB. Then the
denitrification of nitrite and nitrate in the returned sludge by using the residual COD was accomplished in the A/O reactor, and ammonia
was removed via nitrite in it. Last but not least, the residual ammonia was removed in SBR as well as nitrite and nitrate which were
produced by nitrification. The results over 120 d (60 d for phase I and 60 d for phase II) were as follows: when the total nitrogen
(TN) concentration of influent leachate was about 2500 mg/L and the ammonia nitrogen concentration was about 2000 mg/L, the shortcut
nitrification with 85%–90% nitrite accumulation was achieved stably in the A/O reactor. The TN and ammonia nitrogen removal
e ciencies of the system were 98% and 97%, respectively. The residual ammonia, nitrite and nitrate produced during nitrification in
the A/O reactor could be washed out almost completely in SBR. The TN and ammonia nitrogen concentrations of final e uent were
about 39 mg/L and 12 mg/L, respectively. 相似文献
945.
The present study evaluated the potential of white-rot fungal strain Coriolus versicolor to decolorize five structurally di erent dyes
in sequential batch reactors under optimized conditions. The experiments were run continuously for seven cycles of 8 d each. High
decolorizing activity was observed even during the repeated reuse of the fungus, especially when the old medium was replaced with
fresh medium after every cycle. Biodegradation was the dominating factor as the fungus was able to produce the enzyme laccase mainly,
to mineralize synthetic dyes. The nutrients and composition of the medium played important roles in sustaining the decolorisation
potential of the fungus. Corncob was found be an easy and cheap substitute for carbon source for the fungus. Glucose consumption by
the fungus was in accordance to its decolorisation activity and chemical oxygen demand (COD) reduction. 相似文献
946.
947.
Fenton化学氧化法深度处理精细化工废水 总被引:14,自引:1,他引:13
根据某精细化工厂的废水经过长时间的厌氧-好氧生化处理,难以进一步生物降解的特点,采用Fenton试剂进行高级氧化处理。通过实验探讨了不同的H2O2和Fe2+浓度、反应时间、pH等因素对二级生化出水COD去除率的影响。在H2O2投加量为18mmol/L,FeSO·47H2O投加量为12mmol/L,反应时间1.5h,废水的pH=4的条件下,二级生化出水的COD去除率达到82.61%,降到100mg/L以内,达到国家一级排放标准。 相似文献
948.
杂色云芝漆酶和发酵液降解对苯二酚研究 总被引:2,自引:1,他引:1
测定和分析了杂色云芝漆酶和杂色云芝发酵液对对苯二酚的降解反应.通过对不同底物质量浓度下杂色云芝漆酶酶学反应动力学特征分析,求得漆酶Lac A对对苯二酚的酶反应动力学方程V=1.52Cs/(16.55 Cs)和底物抑制反应速率方程γs=1.02/(1 12.86/Cs Cs/137.17).发酵液对对苯二酚的降解反应进程符合一级反应动力学方程lnC=-kt 6,发酵液对对苯二酚的降解反应动力学基本符合Michelis-Menten酶学反应动力学方程Vf=1.77Cs/(3.63 Cs),研究表明Lac A与发酵液对对苯二酚的酶学反应动力学具有较大的相似性,也存在着底物抑制现象,其底物抑制的动力学方程为γs'=1.40/(1 5.75/Cs Cs/278.26).比较漆酶纯酶Lac A和发酵液对对苯二酚反应的Km和Vmax数值,发现杂色云芝发酵液Km较小而Vmax数值较大,说明发酵液较漆酶纯酶具有更高的底物亲和力和催化效率. 相似文献
949.
With the increasing demand for fossil based energy and implementation of progressively strict environmental pollution control
standards, treatment of a large amount of co-produced waters (CPWs) from fossil based energy production has become increasingly
important. Removal of bicarbonate with H2SO4 has been recently studied as a simple and cost-e ective method to decrease the alkalinity
of CPWs. The present work investigates the kinetics of the reaction between H2SO4 and NaHCO3, which could provide the base for
scaling-up the CPW treatment technology. Based on the measured quantity change of the CO2 gas generated from the reaction between
H2SO4 and NaHCO3 with time under specified initial reaction conditions, the reaction orders with respect to H2SO4 and NaHCO3 were
determined. Experiments were also conducted within the temperature of 15–30°C to find various global rate coe cients of the reaction
to calculate the activation energy and the pre-exponential factor of the empirical Arrhenius form of the bicarbonate removal reaction,
which are 197.7 kJ/mol and 3.13 1034 (mol??3:7 L3:7 sec??1), respectively. 相似文献
950.
A kinetic model for the Ti(IV)-catalyzed H2O2/O3 process was established, and the experimental results demonstrated that the model could well describe this ozone-based oxidative system mathematically and chemically. 相似文献