改性粉煤灰处理含铜废水的研究

采用NaOH溶液对粉煤灰进行改性,并研究了粉煤灰和改性粉煤灰对Cu~(2+)的吸附性能。考察了反应时间、吸附剂投加量及溶液pH值对吸附过程的影响,同时研究了粉煤灰和改性粉煤灰吸附Cu~(2+)的动力学和等温线。结果表明:改性后,粉煤灰的吸附性能显著提高。当反应时间为90min、吸附剂投加量为3g、溶液pH值为9时,改性粉煤灰对Cu~(2+)的去除率达到99%以上。粉煤灰和改性粉煤灰对Cu~(2+)的吸附符合拟二级动力学模型和Langmuir吸附等温模型,即符合单分子层吸附理论。     

酸改性粉煤灰对罗丹明B的吸附研究

采用盐酸改性粉煤灰为吸附材料,以罗丹明B的模拟废水为吸附对象,研究了改性粉煤灰的投入量、吸附时间、温度及溶液pH值对吸附效果的影响。研究表明,对50 mL浓度2 mg/L的罗丹明B模拟废水,酸改性粉煤灰的最佳吸附条件是：在50℃下,加入0.09 g的粉煤灰,调节pH值为1.77,搅拌30 min。改性粉煤灰对罗丹明B吸附的脱色率可达98.19%。     

改性粉煤灰对含镍废水的吸附研究

探讨了改性粉煤灰处理含镍废水的影响因素,结果表明：改性粉煤灰的除镍性能与废水pH值、吸附时间、反应温度等因素有关。当pH小于7时,吸附起主导作用,随着pH值的升高,沉淀逐渐起主导作用。通过动力学及热力学研究表明：改性粉煤灰对含镍废水的吸附符合班厄姆吸附动力学方程及Langmuir吸附等温式,即符合单分子层吸附理论,且为自发、吸热过程。     

改性粉煤灰对分散黄染料吸附性能的研究

采用H_2SO_4对粉煤灰进行改性,研究了粉煤灰改性的最佳条件及其对分散黄染料的吸附脱色规律。实验结果表明,分散黄染料溶液浓度70mg·L~(-1),改性粉煤灰用量20g·L~(-1),pH值为2,吸附时间20min,脱色率可达96%以上。改性粉煤灰对分散黄染料的饱和吸附量比原粉煤灰提高一倍。随着吸附温度的升高,改性粉煤灰的吸附能力下降。     

改性粉煤灰处理含磷污水的研究

利用酸对电厂粉煤灰进行改性,并将改性粉煤灰应用于去除废水中的磷,探讨了pH值、吸附接触时间、吸附剂用量、以及温度等对吸附效率的影响。     

改性粉煤灰对苯酚的吸附特性研究

研究了苯酚在改性粉煤灰上的吸附特性。结果表明，改性粉煤灰吸附苯酚速率快，在低pH值下吸附效果更好，等温吸附过程符合Freundlich模型，其吸附等温线为q=1．7081C^0.9248。     

粉煤灰处理含镍废水的研究

以粉煤灰为吸附剂,应用于去除模拟废水中的镍,探讨了吸附时间、吸附剂用量、温度、溶液的pH值对吸附效率的影响。并对粉煤灰用碱进行了改性,改性后的粉煤灰对镍的去除率大幅度提高,可达93%以上。     

粉煤灰的改性及改性效果的研究

选择盐酸和硫酸作为改性剂,对粉煤灰进行了无机改性的研究,分析了pH值、温度、时间等因素对改性效果的影响,结果表明,用盐酸改性过的粉煤灰有更好的吸附效果,对含铬废水的去除率达93%.     

改性粉煤灰处理校园池塘富营养化水体的研究

采用化学改性的粉煤灰为吸附材料,以校园池塘富营养化水体为吸附对象,研究了改性方法、灰水比、粒径、搅拌时间及pH值对CODCr去除率的影响。结果表明,酸改性粉煤灰COD Cr去除效果优于碱改性粉煤灰;弱酸性的水样环境可提高酸改性粉煤灰的吸附效果;当以灰水比1∶10加入过180目筛的酸改性粉煤灰,快速搅拌2 min(160 r/min),慢速搅拌10 min(100 r/min),静置30 min,CODCr去除率可达91%。     

改性粉煤灰处理含磷废水的研究

采用浓硫酸固相反应法对粉煤灰进行改性用于含磷废水的净化,考察了pH值,吸附剂用量,磷初始浓度,反应时间对净化过程的影响。通过实验发现溶液pH值在4-10范围内对磷的吸附过程影响不显著,改性粉煤灰可以在较宽的pH值范围内进行脱磷处理;随着粉煤灰加入量的增加和初始溶液中磷酸根浓度的降低,磷的净化率逐渐增加。对于含磷50 mg/L的溶液,当粉煤灰的投加量为1.5%时,磷的吸附效率可达99.66%,净化后水中含磷量为0.17 mg/L。改性粉煤灰对水中磷的净化过程速度较快,5 min可达到最大净化率。改性粉煤灰对磷的吸附等温线符合Freudlich方程。     

改性粉煤灰处理模拟含酚废水的实验研究

通过对粉煤灰进行改性,研究其对模拟含酚废水中苯酚去除效果.探讨了pH、吸附时间、投加量、吸附温度及水样中苯酚初始浓度对粉煤灰去除苯酚效果的影响.实验表明,选用碱改性的粉煤灰,投加15g/L处理苯酚质量浓度30.0 mg/L的模拟含酚废水,当吸附时间为30 min,pH为6～7时,对苯酚去除率达98％,吸附等温线拟合结果...     

改性粉煤灰对燃煤电厂脱硫废水中氯离子的吸附性能

为了将"以废治废"的理念融入实际工业应用中,开展对燃煤电厂固体废弃物粉煤灰改性后在不同条件下进行脱硫废水的吸附实验研究.结果表明,改性粉煤灰的最佳投加量为25 g/L,此时对废水中Cl-的去除率最大,为56％;在45°C和pH为5的条件下,粉煤灰对Cl-的吸附量最大,在反应约280 min时达到吸附平衡.该吸附过程为吸...     

用硫酸改性粉煤灰处理含磷废水的研究

以硫酸对粉煤灰进行改性用于含磷废水的净化,考察了pH值,吸附剂用量,磷初始浓度,反应时间、反应温度对净化过程的影响。通过实验发现溶液pH值在8~11范围内对磷的吸附过程影响不显著,改性粉煤灰可以在较宽的pH值范围内进行脱磷处理;随着粉煤灰加入量的增加和初始溶液中磷酸根浓度的降低,磷的净化率逐渐增加。对于含磷<80 mg/L的溶液,当粉煤灰的投加量为3%时,反应温度40℃,磷的吸附效率可达97.6%。改性粉煤灰对水中磷的净化过程速度较快,30~40 min可达到最大净化率。     

Study on the phosphate removal from aqueous solution using modified fly ash

In this work the fly ash was modified by sulfuric acid for the removal of phosphate. It was found that modification of fly ash could significantly enhance the phosphate immobilization ability of the fly ash. The specific surface area of the fly ash increased from 8.8 to 32.5 m²/g after treated with sulfuric acid. The modification of the fly ash also resulted in the mobilization of acid-soluble metal ions due to partial or complete dissolution of the metals under the acidic conditions. Both adsorption and precipitation contributed to the removal of phosphate by the modified fly ash but precipitation was a major mechanism of phosphate removal. The experimental results showed that adsorption of phosphate by the modified fly ash was rapid, the removal percentage of phosphate could reach maximum in 5 min. In the range of 5–9, pH did not significantly affect the removal of phosphate and the removal percentage of phosphate increased with the increase of adsorbent dosage. The adsorption of phosphate by the modified fly ash could be described well by Langmuir isotherm equation, the Langmuir constant Q₀ was 9.15 mg g⁻¹. The XRD patterns and the SEM images of modified fly ash after sorption revealed that CaHPO₄·2H₂O was formed in the removal of phosphate. In addition, phosphate also formed precipitate with aluminum and iron.     

改性粉煤灰吸附处理铜冶炼工业废水中Zn~(2+)的研究

研究了粉煤灰改性的工艺条件和静态处理铜冶炼工业废水中Zn2+的效果。试验结果表明:硫酸质量浓度为2mol/L,粉煤灰与硫酸用量比为1︰3.04,在95℃下振荡(振荡频率为170r/min)反应2h时,制得的改性粉煤灰吸附效果最好。在未调节该废水pH值条件下,当改性粉煤灰用量为0.007g/mL,吸附时间为65min,吸附温度为25℃时,Zn2+的去除率为93.17%。处理后的水中Zn2+残留浓度达到了国家污水综合排放标准(GB8978-1996)一级标准。吸附过程符合Freundlich吸附等温式:lgQe=0.4511+5.3584lgCe,热力学参数为:△H=-1.7892J/mol,△S=0.5254J/(K·mol),△G=-162.661J/mol。在相同条件下,未改性粉煤灰对Zn2+的去除率为82.99%,通过硫酸改性使粉煤灰的吸附性能得到较大提高。     

Low cost adsorbents obtained from ash for copper removal

We investigated the utilization of ash and modified ash as a low-cost adsorbent to remove copper ions from aqueous solutions such as wastewater. Batch experiments were conducted to determine the factors affecting adsorption of copper. The influence of pH, adsorbent dose, initial Cu²⁺ concentration, type of adsorbent and contact time on the adsorption capacity of Cu²⁺ from aqueous solution by the batch adsorption technique using ash and modified ash as a low-cost adsorbent were investigated. The optimum pH required for maximum adsorption was found to be 5. The results from the sorption process showed that the maximum adsorption rate was obtained at 300 mg/L when a different dosage of fly ash was added into the solution, and it can be concluded that decreasing the initial concentration of copper ion is beneficial to the adsorption capacity of the adsorbent. With the increase of pH value, the removal rate increased. When the pH was 5, the removal rate reached the maximum of over 99%. When initial copper content was 300 mg/L and the pH value was 5, the adsorption capacity of the zeolite Z 4 sample reached 27.904 mg/g. The main removal mechanisms were assumed to be the adsorption at the surface of the fly ash together with the precipitation from the solution. The adsorption equilibrium was achieved at pH 5 between 1 and 4 hours in function of type of adsorbent. A dose of 1: 25 g/mL of adsorbent was sufficient for the optimum removal of copper ions. For all synthesized adsorbents the predominant mechanism can be described by pseudo-second order kinetics.     

粉煤灰吸附处理含铬废水的试验研究

利用经2 mol/L的硫酸改性的粉煤灰,来研究粉煤灰吸附处理实验室模拟含铬废水。实验结果表明：处理100 mL含六价铬浓度为50 mg/L的废水,调节pH值2～3,投加8 g改性粉煤灰,反应80 min后六价铬的去除率达到90%以上;吸附符合Freundlich等温吸附式。利用粉煤灰吸附处理含铬废水,具有处理效果好,操作简单,运行费用低等优点,因此,粉煤灰可以作为一种有效的吸附剂来处理含铬废水。