臭氧催化氧化降解煤化工生化进水有机物的实验及机理

研究了臭氧催化氧化降解煤化工生化进水有机物的工艺条件及机理。本文以新疆某煤化工生化进水为研究对象,确定废水中难降解有机物的种类及含量,开展臭氧催化氧化试验,探讨工艺条件对化学需氧量（COD）的去除率,最后以溶解性有机物（DOM）为对象,解析废水难降解有机物的降解规律。结果表明：废水中主要为苯酚及腐殖酸;最佳工艺参数为催化剂投加量1.2L/L、臭氧浓度500mg/L、臭氧通气量2.5m³/h;反应后各组分的UV₂₅₄均下降,去除率从高到低为疏水性中性物质（HoN）>亲水性碱性物质（HiB）>疏水性碱性物质（HoB）>亲水性酸性物质（HiA）>疏水性酸性物质（HoA）>亲水性中性物质（HiN）,富里酸类、腐殖酸类、蛋白质类及溶解性生物代谢产物等荧光强度均降低。     

臭氧-过氧化氢氧化预处理H酸废水

采用工业生产中排放的H酸废水作为研究对象,探讨了臭氧-H2O2氧化的预处理方法对该废水的处理效果。结果表明：在单独臭氧氧化反应体系中,初始CODCr的质量浓度为1 200 mg/L,pH值为7,臭氧氧化时间在20 min（通量为1 L/min）时,CODCr和色度去除率分别为36.7%和95%。单独H2O2氧化反应体系中,H2O2投加量为8 mL/L时,CODCr去除率为7.7%,H2O2投加量达到60 mL/L时,CODCr去除率最高仅达到25.6%。臭氧-H2O2联用体系中,相同初始CODCr浓度、pH值、臭氧氧化时间及臭氧通量条件下,质量分数为3%的H2O2溶液投加量为8 mL/L时,CODCr和色度去除率分别可达48.8%和98%。因此,臭氧-H2O2氧化的预处理方法对H酸废水降解效果良好,且明显优于单独臭氧氧化以及单独H2O2氧化。     

新型铁铈复合氧化物催化臭氧氧化工艺去除对硝基苯酚

对硝基苯酚(4-NP)作为一种难降解的有机污染物,在自然环境中半衰期较长,对水生生物及水体环境均有不利影响.采用水热法制备新型铁铈复合氧化物,将其作为臭氧催化剂用于去除水中的4-NP.采用单因素试验,探究铁铈摩尔比、臭氧浓度、催化剂投加量、初始pH等因素对4-NP去除效果的影响.结果表明:在铁铈摩尔比为10:1、水中臭...     

钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响

考察了间歇反应器中钙离子存在下腐殖酸分子在TiO2颗粒表面的吸附行为,进而以125 W (Emax=365 nm) 汞灯为中心光源,考察了钙镁离子对二氧化钛光催化氧化水中腐殖酸的影响. 结果表明,在腐殖酸初始浓度C0=20 mg/L, [Ca2+]=80 mg/L, pH=7和TiO2=1 mg/ml实验条件下,经2.5 h的光催化反应,腐殖酸的脱色率为100%,氧化分解率接近100%,矿化率大于95%.     

臭氧氧化法强化处理纤维素乙醇废水研究

为提高纤维素乙醇废水厌氧出水的可生化性,采用臭氧氧化法对其进行强化处理,考察了反应时间、臭氧投加量、初始p H及反应温度对纤维素乙醇废水可生化性、COD和氨氮去除效果的影响。结果表明,在初始pH为8~10,臭氧投加量为5 g/h,反应时间为80 min,反应温度为30℃的最优条件下,出水COD为1 450 mg/L左右,COD去除率稳定在35%左右;出水氨氮为220 mg/L左右,氨氮去除率稳定在40%以上,出水BOD_5/COD由0.1提高到0.3左右,废水的可生化性得到较大程度的提高。     

不溶性腐殖酸吸附Cr(Ⅵ)的研究

研究了不溶性腐殖酸对六价铬的吸附作用。进行了反应接触时间、pH值、IHA投加量、光照条件、温度等对反应的影响研究,确定了最佳反应条件,同时应用未处理的腐殖酸进行对比研究,说明不溶性腐殖酸的作用效果。试验表明在反应接触时间60 min、pH值为7左右、不溶性腐殖酸投加量为5 g/L和Cr(Ⅵ)的质量浓度为5.36 mg/L的条件下,不溶性腐殖酸对铬离子去除可达95%,比未处理的腐殖酸对铬离子去除提高近1倍。并绘制了不溶性腐殖酸对铬离子的反应动力学曲线和吸附等温线。     

非均相催化臭氧化新工艺处理含氰废水的研究

采用了非均相催化臭氧化新工艺处理低浓度含氰废水。采用间歇催化臭氧化实验装置对工艺参数进行了考察,确定了最佳工艺条件：反应温度为30℃,活性炭投加量为14 g/L,臭氧投加速度为30 mg/min,pH=10。     

臭氧氧化法处理硝基苯废水实验研究

采用臭氧氧化法处理硝基苯溶液,考察了反应时间、硝基苯浓度、溶液pH、臭氧流量等因素对硝基苯降解率的影响。研究结果表明：初始浓度200 mg/L时,pH 9.5、臭氧流量为300 mg/h,经30 min后硝基苯去除率达到95.3%以上。硝基苯降解反应符合一级反应动力学。TOC降解速率低于硝基苯分子降解速率,反应30 min后,TOC去除率比硝基苯去除率低45%左右,表明伴随着硝基苯的分解,由？OH或臭氧和硝基苯分子作用生成一系列中间产物。     

臭氧、臭氧/双氧水催化氧化深度处理化工废水

对比了臭氧、臭氧催化氧化、臭氧/双氧水和臭氧/双氧水催化氧化4种工艺深度处理化工废水的效果,结果表明,当进水COD和色度分别为95.7 mg/L和90倍时,4种工艺出水的COD去除率分别为23.66%、26.77%、29.24%、32.97%,色度去除率分别为64.44%、64.44%、82.22%、82.22%,催化剂和双氧水均能小幅强化臭氧氧化效果。连续臭氧氧化可使出水COD降至20 mg/L,同时当臭氧投加量为60 mg/L时,4种工艺出水均具有一定的可生化性,满足后序生化工艺的需求。     

臭氧氧化处理苯胺废水

采用臭氧氧化法处理苯胺溶液，考察了反应时间、苯胺浓度、溶液pH、臭氧流量等因素对苯胺降解率的影响。研究结果表明：初始浓度200mg／L时，pH值9．0、臭氧流量为300mg／h，经10min后苯胺去除率达到99％以上。苯胺降解反应符合一级反应动力学。TOC降解速率低于苯胺分子降解速率，反应30min后，TOC去除率比苯胺去除率低40％左右，表明伴随着苯胺的分解，生成一系列中间产物。     

Adsorption of humic acid onto pillared bentonite

Pillared bentonite, a clean and cost-effective adsorbent with high specific areas of 111.3 m²/g and high basalspacing of 1.98 nm, was prepared for the removal of humic acid from water. It is effective for the removal of humic acid with a high adsorption capacity of 537 mg/g, and adsorption is favored under acid conditions. Adsorption is dependent on ionic strength and dissolved NaCl enhanced adsorption. Over 97% removal was observed under natural pH conditions from humic acid solutions containing 10 mg/L Ca²⁺ or Mg²⁺, which suggests that pillared bentonite can be an effective adsorbent for the removal of humic acid for drinking water purification. Pillared bentonite can be regenerated with NaOH, and the regeneration efficiency reaches 83% and 85% when the concentration of NaOH reaches 0.025 and 0.05 mol/L. The mechanism for adsorption of humic acid to pillared bentonite is discussed.     

回流固定床臭氧催化氧化煤化工反渗透浓水

设计了一种具有回流的固定床臭氧催化氧化反应装置,对浸渍法制得的α-Fe₂O₃/γ-Al₂O₃催化剂的性能进行了表征,并利用其在回流固定床反应装置中对煤化工反渗透浓水的臭氧催化氧化性能进行了研究。结果表明：α-Fe₂O₃/γ-Al₂O₃的比表面积、平均孔径、总孔容和活性组分α-Fe₂O₃含量分别为161.74m²/g、10nm、0.4533cm³/g和8.73%。反渗透浓水COD去除率随催化剂装填高度、臭氧投加浓度和过氧化氢投加量的增加而均呈现为先增加、后降低的变化趋势,回流可显著地提高废水COD去除率,适宜的催化剂装填高度、臭氧投加浓度、过氧化氢投加量和回流比分别为350mm、300mg/L、150mg/L和50%,臭氧催化氧化反渗透浓水的COD去除率达74.33%。煤化工反渗透浓水中大部分溶解性有机物和腐殖酸类物质均被臭氧催化氧化分解。     

Application of an ozonation–adsorption–ultrafiltration system for surface water treatment

Investigations are presented on the effect of the preliminary ozonation on ultrafiltration (UF) and powdered activated carbon (PAC) /UF process performance, especially on permeate flux decline and the effectiveness of model organics removal. Flat membranes from regenerated cellulose were used. A model solution was prepared as a mixture of humic acids and phenol. PAC dosage was equal to 100 mg/l⁻¹. The ozone dosages were in the range of 1–3 mg O₃ l⁻¹ (0.2–0.6 mg O₃/mg TOC). It was found that the most advantageous configuration was preliminary ozonation with an ozone dosage of 0.4 mgO₃/mg TOC–UF. The permeate flux reached a value equal to the pure water flux value. Moreover, a very high effectiveness of model organics removal was obtained: TOC was reduced by about 96% and UV₂₅₄ absorbance was removed completely. When PAC was added to the feed containing humic acids without ozonation, a drop in a permeate flux was observed compared to UF. Similarly, the addition of PAC to feed treated with ozone resulted in a significant drop in the permeate flux in comparison with pure water flux, regardless of ozone dosage applied.     

腐植酸树脂处理含重金属离子废水可行性探讨

利用泥炭为原料制备腐植酸树脂。在动态条件下,研究了腐植酸树脂对重金属离子Zn2+、Ni2+的吸附效果及吸附条件并探讨了吸附与解吸再生机理:主要吸附形式为离子交换吸附和络合吸附。实验结果表明,在20℃,流速为4mL/min,pH值为5.0～7.0条件下,含Zn2+、Ni2+质量浓度均为70mg/L的废水,经腐植酸树脂处理后,Zn2+、Ni2+去除率可达98%以上,且处理后废水近中性。含Zn2+、Ni2+质量浓度分别为32.5mg/L和29.4mg/L,pH值为5.9的电镀废水,经腐植酸树脂处理后,废水中Zn2+、Ni2+含量显著低于国家排放标准允许值。     

腐殖酸树脂处理含Zn^2＋、Ni^2＋废水的研究

利用泥炭为原料制备出腐殖酸树脂,在动态条件下,研究了腐殖酸树脂对重金属离子Zn^2＋、Ni^2＋的吸附效果及吸附条件。结果表明,在20℃,流速为4mL／min,pH值为5．0～7．0,含Zn^2＋、Ni^2＋浓度分别为70mg／L的废水经过腐殖酸树脂处理,Zn“、Ni。’去除率可达98％以上,且处理后的废水pH值近中性。含Zn^2＋、Ni^2＋浓度分别为32．5mg／L和29．4mg／L,pH值为5．9的电镀废水经腐殖酸树脂处理后,废水中Zn^2＋、Ni^2＋含量明显低于国家排放标准。     

二级牡蛎壳固定床-MBR工艺深度处理尾水研究

利用臭氧的强氧化、微生物降解以及MBR的强截留作用,构建了二级牡蛎壳固定床,即OOFR(臭氧-牡蛎壳固定床)-AOFB(曝气-牡蛎壳生物固定床)-MBR深度处理污水厂尾水工艺流程。为期90 d的小试结果表明,该工艺可高效地去除尾水中的C、N、P以及悬浮物。臭氧边界投加量为40~110 mg/L,在臭氧最佳投加量90 mg/L下,系统的COD、NH4+-N、TP的平均去除率分别达83%、99%、65%,平均出水COD、NH4+-N、TP分别为6、0.1、0.14 mg/L,浊度低于0.1 NTU,p H为7.4~7.8,完全满足反渗透处理进水的要求。     

臭氧氧化法预处理焦化废水的试验研究

为了提高焦化废水的可生化性,对焦化废水进行了臭氧氧化预处理的试验研究.结果表明:当废水初始pH值为9,气水反应时间为3 min,臭氧投加量为30 mg/L时,废水m(BOD5)/m(CODCr)值由原水的0.068提高到0.281.臭氧用于焦化废水的预处理是可行的,有利于焦化废水的后续生化处理.     

Kinetics and Mechanism of Humic Acids Degradation by Ozone in the Presence of CeO2/AC

This work investigated the catalytic ozonation of humic acids extracted from landfill leachate in the presence of CeO₂/AC with focus on the kinetics of humic acids degradation. It was confirmed that the degradation of humic acids mainly took place in the solution bulk. The direct and indirect reaction constants of ozone against humic acids were determined. By analyzing the contributions of direct ozone oxidation and indirect ?OH radicals oxidation to humic acids removal, it was found that ?OH radicals oxidation predominated at all pH, indicating that the catalytic ozonation of humic acids with CeO₂/AC involved ?OH radicals mechanism.     

微波-载铜活性炭催化氧化降解腐殖酸

以粉末活性炭(PAC)和颗粒活性炭(GAC)为载体,采用浸渍焙烧法制备了负载铜氧化物的活性炭催化剂,考察了其表面结构、元素组成及BET参数;以腐殖酸模拟废水为对象,研究了微波?载铜活性炭催化氧化降解腐殖酸的效果和影响因素,探讨了微波?催化氧化协同H2O2降解腐殖酸的机理. 结果表明,载铜活性炭比未负载铜的活性炭对腐殖酸的降解率更高,且Cu/PAC的催化效果远优于Cu/GAC,两种催化剂最佳的微波?催化氧化条件分别为Cu/PAC投加量1 g/L, H2O2投加量0.9 mL/L, pH=3,微波功率400 W,微波时间4 min和Cu/GAC投加量8 g/L, H2O2投加量1.5 mL/L, pH=6,微波功率400 W,微波时间4 min,该条件下腐殖酸的去除率分别为93.91%和91.59%. 微波、H2O2和催化剂协同作用对腐殖酸高效降解有决定性作用.     

Ultraviolet-Enhanced Ozonation of Organic Compounds: 1,2-Dichloroethane and Trichloroethylene as Model Substrates

1,2–Dichloroethane (DCE) and trichloroethylene (TCE) were used as model compounds to study the oxidation of organic chemicals by ozone/ultraviolet radiation, ozone, and hydrogen peroxide/ultraviolet radiation. It was found that ozone/ultraviolet radiation oxidized both 1,2–dichloroethane and trichloroethylene in batch systems, at pH = 2 (phosphate buffer). At ozone concentrations in the 1 to 5 mg/L range, the reaction was first order in both ozone and substrate. At pH = 2 and initial ozone concentration 2.2–2.6 mg/L, rate constants (k)Q = 25 and 130 M^-1sec^-1 were observed for the ozone/ultraviolet radiation oxidation of DCE and TCE, respectively. The rat e constants for ozone oxidation of DCE and TCE without ultraviolet radiation were 4.3 and 47 M^-1sec^-1, respectively.

The higher rate of TCE oxidation implies that direct reaction occurs with the double bond. Finite reaction rate of DCE with ozone, and substantial increases in rate at higher pH imply the participatation of hydroxyl radicals in the oxidation of both compounds. For example, at pH = 7, initial ozone concentration of 2.3 mg/L, the k_o for TCE oxidation by ozone/ultraviolet radiation is approximately 500 M^?1 sec^?1 almost too fast to measure in a batch system.The rate also is increased by increased ultraviolet radiation intensity, and by the presence of hydrogen peroxide, which acts as a catalyst.