粉煤灰聚硅酸铝铁絮凝剂的制备及处理洗煤废水研究

将粉煤灰与固体氢氧化钠混合后焙烧活化,经酸浸、静置和聚合等步骤制备聚硅酸铝铁絮凝剂,研究了活化条件、静置时间和聚合条件等因素对合成的影响,并对洗煤废水进行处理。结果表明,当碱灰比1.2、活化温度750℃、活化时间1.5h,产物被盐酸完全溶解,静置15min,可获得聚合度较低、活性较强的聚硅酸。正交实验表明,聚合条件对高浊水去除率的影响顺序为:pH值熟化时间n(Si):n(Al)熟化温度n(Si):n(Fe),最佳聚合条件为:n(Si):n(Al)=1:0.9、n(Si):n(Fe)=1:0.3、p H=2、熟化温度80℃、熟化时间2.5h。洗煤废水处理结果表明,当pH=7,投加量为1g/L,搅拌时间为35min,COD去除率和氨氮去除率最高,分别为95.7%、94.2%,剩余浊度为17NTU,经处理后的废水达到洗煤废水污染物排放标准。     

Al-Fe-Mg三阳离子聚硅酸絮凝剂的研发

为了提高腈纶废水的絮凝处理效果,研发了一种Al-Fe-Mg三阳离子聚硅酸絮凝剂。通过正交实验研究了金属溶液浓度、硅与金属比例以及铝、铁、镁之间比例对絮凝剂制备的影响。然后,将制备好的絮凝剂药液投加入废水中,研究其投加量及pH对废水处理的影响。结果表明,将聚硅酸溶液倾倒入(金属溶液浓度为0.02mol·L~(-1),Si与金属摩尔比为2∶1,金属铝铁镁摩尔比为3∶1∶2)金属溶液搅拌快速搅拌5min后静置12h,在此条件下制备的铝铁镁絮凝剂效果最佳,并且硅与金属比例是复合絮凝剂的主要影响因素,去浊率可达99.59%。     

~(29)SiNMR谱研究硅溶胶、水玻璃和硅酸乙酯水解液的分散状态

硅溶胶、水玻璃和硅酸乙酯水解溶液的~(29)Si NMR谱表明:1.凡硅溶胶都属于典型的胶体溶液。2、水玻璃溶液在SiO_2/Na_2O摩尔比≤2时,基本上属于可溶性二氧化硅体系,若>2,则随摩尔比增加,胶体成分增加。3、硅酸乙酯水解液在水解时,若H_2O/C_2H_5O—摩尔比<0.5,其组成为多硅酸乙酯溶液;若≥0.5,为小粒子胶体和多环硅酸溶液。     

不同铝源合成的β沸石结构表征与热分解行为的研究

考察了以固体硅胶为硅源、 NaAlO2及α Al2O3· H2O两种铝源、以及不同晶化混合液的 SiO2/Al2O3比（ 15～ 50）对β沸石合成的影响。通过 XRD、 DSC/TGA、 29Si NMR及 ICP研究表明,以 NaAlO2为铝源合成的β沸石更易形成 Si(0Al)、 Si(1Al)、 Si(O－ )配位,且化学 SiO2/Al2O3比与晶化混合液 SiO2/Al2O3比基本一致,以α Al2O3· H2O为铝源合成的β沸石更易形成 Si(0Al)、 Si(O－ )、 Si(2Al)配位,且化学 SiO2/Al2O3比低于晶化混合液的 SiO2/Al2O3比; TGA失重量随β沸石 SiO2/Al2O3比增加而增加, DSC吸热量随β沸石 SiO2/Al2O3增加而减少。     

氢化物发生原子荧光法测定聚氯化铝中的砷含量

建立了氢化物发生原子荧光法测定聚氯化铝中砷含量的检测方法。将聚氯化铝样品用硫酸溶解,蒸至近干,用氢化物发生原子荧光法测定其中的砷含量。在最佳测定条件下,砷的质量浓度在0~10.0μg/L范围内与荧光强度呈良好的线性关系,相关系数r=0.999 3,砷的检出限为0.03μg/g,样品加标回收率为82.5%~90.0%,测定结果的相对标准偏差为1.5%~1.9%。该法具有快速、准确、灵敏度高等优点。     

Sol-gel法制备S_2O_8~(2-)/ZrO_2-SiO_2及其微波辐射下催化合成乙酸正丁酯的研究

以Zr O(NO3)2和正硅酸乙酯(TEOS)为原料,采用溶胶-凝胶法制备固体超强酸S2O82-/Zr O2-Si O2催化剂,以微波辐射下冰醋酸和正丁醇合成乙酸正丁酯为探针反应,探究了催化剂制备条件对催化活性的影响及反应条件对酯化反应的影响。运用Hammett指示剂法,BET法,XRD,TEM和FT-IR对催化剂进行了表征。结果表明,催化剂的最佳制备条件为nZr∶nSi=1∶10,焙烧时间3.0h,焙烧温度550℃,(NH4)2S2O8浸渍液浓度0.6 mol·L-1。微波辐射下酯化反应最优条件为:醇酸摩尔比2.2∶1,催化剂0.8g,反应时间35min,功率600W,此时产率为93.5%。该法制得的催化剂酸强度H0≤-13.16为超强酸,催化剂比表面较大,Si O2为无定形态,Zr O2为四方晶相,Zr O2在Si O2上分布相对均匀,且Si O2分布较为松散,基本呈多孔网状结构。     

聚硅酸硫酸铁/壳聚糖复合絮凝剂的制备及其在废水处理中的应用

制备了无机高分子复合絮凝剂聚硅酸硫酸铁（PFSS）和助凝剂壳聚糖（CTS）,考察了影响合成及絮凝剂应用的因素,探讨了其组成、投加量以及pH值对城市废水絮凝效果的影响,通过对模拟废水和城市废水絮凝试验,得出最佳的合成和应用条件：n（Fe）∶n（Si）=1∶1,PFSS的碱化度为1.5,聚合硫酸铁（PFS）的pH=2,聚硅酸（PS）的活化时间为1.5 h;n（PFSS）∶n（CTS）=5∶1,投加量为(20+4) mg/L,pH值的范围为6～9,沉降时间为15 min。 复合絮凝剂（PFSS-CTS）在最佳条件下浊度、色度、COD的去除率分别达到95.04%、91.26%和83.45%。     

敞开体系制备含铝中孔分子筛

在敞开体系中 ,以工业用水玻璃为硅源 ,以Al2 (SO4) 3 为铝源 ,以三甲基十六烷基溴化铵 (CTMAB)为模板剂 ,用H2 SO4调节浆料的pH值 ,在浆料混合物摩尔比组成为n(SiO2 )∶n(Na2 O)∶n(CTMAB)∶n(Al2 (SO4) 3 )∶n(H2 O) =7∶2 .0 8∶1.4∶(0 .0 875～ 0 .7)∶5 30的范围内 ,10 0℃搅拌晶化 2 4h ,合成出了含铝中孔分子筛 .利用XRD ,IR和化学分析对产物晶体的长程有序性和骨架铝进行了表征 ,讨论了n(Si) /n(Al)的摩尔比值和浆料pH值对分子筛晶化的影响 .     

对硅酸聚合机制反应级数的验证

用胶凝法研究酸化了的不同摩尔比 (Si O2 /Na2 O)的硅酸钠溶液的胶凝速度 ,发现在恒盐条件下 ,硅酸胶凝速度常数是 2 ,这个结果和我们过去所提出的硅酸聚合机制符合一致。     

冷原子荧光光谱法测定净水剂聚氯化铝中汞含量

提出了冷原子荧光光谱法测定净水剂聚氯化铝中痕量汞,采用断续流动进样,并对仪器的工作条件负高压、灯电流、载气流量、屏蔽气流量作了优化。在优化条件下,荧光强度与汞的质量浓度在0.1～2.0μg.L-1范围内呈线性关系,检出限(3s)为0.05μg.L-1。按此方法分析了聚氯化铝样品,汞测定值的相对标准偏差(n=7)为1.93%。     

不同制备工艺聚硅氯化铝的红外光谱和晶貌研究

聚硅金属盐 (主要是铝盐和铁盐 )是一类新型高效无机高分子混凝剂 ,不同的制备工艺会获得分子相对质量不同 ,分子结构有差异 ,因而混凝效果与稳定性能明显不同的产品。由于基础研究过于薄弱 ,严重影响了其实行大规模工业生产[1] 。聚硅氯化铝 (ＰＡＳＣ)属于聚硅金属盐 ,它的制备大多采用将聚硅酸与铝盐混合 ,在陈化中令其自然聚合 (或适当加热 )的方法[2～ 4 ] 。作者在该方法的基础上增加碱化聚合手段 ,继而引入代号为Ａ的聚合助剂 ,使制得的ＰＡＳＣ具有更好的混凝效果[5] 。为此 ,对不同制备工艺的ＰＡＳＣ进行红外光谱和晶形貌象研究 ,…     

Fluorescence Probe of 10-Phenyl-acridone-2-sulfonyl Chloride and Its Application for Determination of Free Aliphatic Amines in Environmental Samples by HPLC with Fluorescence Detection and APCI-MS

A simple and sensitive method for the determination of free aliphatic amines using 10-phenyl-acridone-2-sulfonyl chloride (PASC) as a labeling reagent by high-performance liquid chromatography with fluorescence detection and online mass spectrometry identification (HPLC-FLD-MS) has been developed. Derivatization conditions including reagent concentration, buffer pH, reaction time and temperature were optimized. PASC reacted with aliphatic amines at 50 °C for 4 min in aqueous acetonitrile (ACN) in the presence of sodiumtetraborate–NaOH buffer (0.10 mol L⁻¹, pH 9.0) to give high yields of PASC-amine derivatives. Derivatives exhibited intense fluorescence with an excitation maximum at λ_ex 265 nm and an emission maximum at λ_em 418 nm. The separation of derivatives was performed by a reversed-phase Hypersil BDS C8 column in combination with a gradient elution. The identification of derivatives was carried out by online post-column mass spectrometry with atmospheric pressure chemical ionization (APCI) source in positive-ion detection mode. Excellent linear responses were observed with the correlation coefficients of larger than 0.9997, and detection limits (at a signal-to-noise of 3:1) were from 3.0 to 24.3 fmol. Comparing with 10-ethyl-acridine-2-sulfonyl chloride (EASC), PASC exhibited more intense fluorescence and ultraviolet absorbance. The proposed method is sensitive and reproducible for the determination of aliphatic amines from water and soil samples.

     

Fe(0)/Cu双金属还原与Fenton氧化集成工艺处理印染生化尾水树脂脱附液的研究

通过比较Fe(0)和Fe(0)/Cu还原工艺处理印染生化尾水树脂脱附液的效果,发现Fe(0)/Cu双金属还原对脱附液TOC和UV254去除率均优于Fe(0)。若将Fe(0)/Cu双金属还原与Fenton氧化工艺集成可以进一步提高处理效果。该组合工艺处理后,TOC去除率高达66%,UV254去除率高于90%,脱附液的BOD5/CODcr从低于0.1升高至0.38左右。由此可见,该组合工艺对复合功能树脂碱脱附液具有良好的处理效果,处理后废水的毒性降低,可生化性显著提高,为其返回生物系统进一步生化降解提供了较好的保证。     

W元素掺杂CeO2非均相电芬顿催化剂高效处理含油污水

制备了W元素掺杂的CeO₂复合材料, 通过扫描电子显微镜、 透射电子显微镜、 X射线衍射和X射线光电子能谱等对W-CeO₂-0.4催化材料进行表征. 结果表明, 具有不规则片状形貌的W元素掺杂CeO₂复合材料提高了单一CeO₂的类芬顿催化效果; 将其作为非均相电芬顿催化剂对含油污水的处理效果明显优于电吸附和物理吸附过程. 进一步的参数优化处理实验发现, 在电压为4 V, pH=3时, 采用W-CeO₂-0.4作为催化剂的条件下, 对含油污水的净化能力在90 min内达到了99.8%, 总有机碳(TOC)去除率达到了约90%, 化学需氧量(COD)去除率达到了76%.     

城市污水处理过程中有机污染物三维荧光特性的变化规律

采用三维荧光光谱法研究了城市污水处理过程中溶解性有机物的三维荧光特性变化规律。研究结果表明,生活污水中荧光类溶解性有机物主要以类蛋白有机物、UV腐殖质和可见腐殖质为主;污水生物处理前后特征荧光峰中心位置和强度均发生明显的改变,表明污水中有机物的相对组成和含量随生物处理过程而变化。三维特征荧光参数可以反映污水处理过程中污染物的种类、性质和含量变化等丰富信息。其测定迅速简便、灵敏度高,可用于污水处理效果的定性分析、定量评价,易于实现污水处理过程的实时在线监测,指导污水处理工艺的设计、运行、管理和控制。     

Synthesis and performances for treating oily wastewater of polyether copolymers based on polyethyleneimine

The demulsification of the oily wastewater generated in the oil recovery process is very important in the crude oil exploitation. In present work, 10 block copolymers based on polyethyleneimine were synthesized, and their performances for treating oily wastewater were studied. The evaluation of demulsification efficiency, the effects of temperature, and the dosage on the treatment of oily wastewater by prepared copolymers were also investigated. To explore the causes of the differences, the interface activity of prepared copolymer molecules at water‐oil interface was investigated by the interfacial tension, and a mechanism diagram of demulsification of wastewater by the prepared copolymers was proposed. The demulsification of wastewater could be divided into 3 processes that were (1) adsorption, (2) congestion, and (3) coalescence. The prepared copolymer molecule acted as a hand in the oily wastewater to achieve the demulsification.     

Liquid-phase adsorption: Characterization and use of activated carbon prepared from diosgenin production residue

The adsorption behavior of activated carbon (AC) prepared from the residue of diosgenin by-product was characterized. The adsorption capacities of AC such as iodine, phenol and methylene blue (MB) are 933.28, 145.38 and 165 mg/g, respectively. The results of MP analysis and BJH method show AC has developed micropore and mesopore volumes, which are 0.1621 and 0.2623 cm³/g respectively, with the mean pore diameter of 1.49 nm. Comparison of the liquid phase adsorption capacities of AC to the standard activated carbon (SAC) and the commercial activated carbon (CAC) for wastewater treatment showed AC was superior to SAC and CAC. Experiments on phenol and MB adsorption and COD and chroma removal from diosgenin wastewater were carried out under different conditions of contact time, temperature, concentration, adsorbent dose and pH. The removal of COD and chroma of 10-multiple wastewater is 92.46 mg/g and 88 %, respectively. Adsorption parameters for the Langmuir and Freundlich isotherm models were determined. At lower temperatures, the data for phenol and COD fitted Freundlich model better than Langmuir model and vise versa for MB and chroma. Adsorption followed second-order kinetics. The study proves that AC prepared from the residue of diosgenin by-product can be used as adsorbent for the treatment of diosogenin wastewater as a cost-effective approach of resource recycle of Discorea zingiberensis C.H. Wright.     

Ce3+电催化降解甲基橙模拟废水的研究

对添加Ce3+的甲基橙模拟废水进行了电催化处理实验,考察了Ce3+电催化降解甲基橙的反应动力学;为探讨Ce3+电催化降解甲基橙的脱色机理,将废水分别置入有隔膜和无隔膜电解槽中,在不同的条件(Ce3+的投加方式、位置和搅拌方式)下进行电解,测定分析了废水在电解过程中铈含量、甲基橙浓度、COD及体系紫外-可见吸收光谱图的变...     

Cultivation of Green Algae Chlorella sp. in Different Wastewaters from Municipal Wastewater Treatment Plant

The objective of this study was to evaluate the growth of green algae Chlorella sp. on wastewaters sampled from four different points of the treatment process flow of a local municipal wastewater treatment plant (MWTP) and how well the algal growth removed nitrogen, phosphorus, chemical oxygen demand (COD), and metal ions from the wastewaters. The four wastewaters were wastewater before primary settling (#1 wastewater), wastewater after primary settling (#2 wastewater), wastewater after activated sludge tank (#3 wastewater), and centrate (#4 wastewater), which is the wastewater generated in sludge centrifuge. The average specific growth rates in the exponential period were 0.412, 0.429, 0.343, and 0.948 day^?1 for wastewaters #1, #2, #3, and #4, respectively. The removal rates of NH₄–N were 82.4%, 74.7%, and 78.3% for wastewaters #1, #2, and #4, respectively. For #3 wastewater, 62.5% of NO₃–N, the major inorganic nitrogen form, was removed with 6.3-fold of NO₂–N generated. From wastewaters #1, #2, and #4, 83.2%, 90.6%, and 85.6% phosphorus and 50.9%, 56.5%, and 83.0% COD were removed, respectively. Only 4.7% was removed in #3 wastewater and the COD in #3 wastewater increased slightly after algal growth, probably due to the excretion of small photosynthetic organic molecules by algae. Metal ions, especially Al, Ca, Fe, Mg, and Mn in centrate, were found to be removed very efficiently. The results of this study suggest that growing algae in nutrient-rich centrate offers a new option of applying algal process in MWTP to manage the nutrient load for the aeration tank to which the centrate is returned, serving the dual roles of nutrient reduction and valuable biofuel feedstock production.     

Determination of the Organics in Trimethylolpropane Wastewater

Organic components play a pivotal role in the treatment of trimethylolpropane wastewater; therefore, research aimed at gaining a better understanding of these components can aid in developing potential treatment methods to remove these pollutants. Thus, the use of liquid–liquid extractions coupled with gas chromatography–mass spectrometry is reported to examine the semivolatile organic components present in trimethylolpropane wastewater, while purge-and-trap coupled with flame ionization detection was used to determine the volatile organic components. Several factors which could affect the precision of the analytical method in pretreatment and detection steps were optimized. These techniques exhibited good linearity (determination coefficients greater than 0.9899), good intraday precision (less than 4.26%), and good interday precision (less than 13.09%). The optimized method was used for the determination of 23 organic components in trimethylolpropane wastewater. The main components were 2-ethylacrolein, butanoic acid, 1-hexanol, 2-ethyl-, trimethylolpropane, butyraldehyde, and toluene.