活性炭吸附法处理亚甲基蓝废水的研究

研究了活性炭对水溶液中亚甲基蓝的吸附,通过实验得到了25℃及30℃活性炭吸附亚甲基蓝的吸附平衡数据,从吸附等温线可看出亚甲基蓝水溶液吸附符合Langmuir型。以及在等温吸附条件下,通过改变不同的参数,分别测定了亚甲基蓝废水吸附过程的穿透曲线。     

枸杞杆制活性炭对亚甲基蓝的吸附研究

以宁夏农业废弃物枸杞杆为原料,用不同的活化剂分别制备磷酸-活性炭（P-AC）、氢氧化钾-活性炭（K-AC）、磷酸-氢氧化钾-活性炭（P-K-AC）,利用比表面积测试（BET）、X射线衍射（XRD）、红外光谱（FT-IR）、扫描电镜（SEM）解析活性炭的孔结构和表面特性,并探究活性炭对水溶液中亚甲基蓝（MB）的去除效果。研究结果表明：P-K-AC比P-AC、K-AC具有更大的比表面积（1 519.84 m²/g）和总孔体积（0.81 cm³/g）,P-AC、K-AC、P-K-AC的平均孔径分别为5.28、2.58、1.99 nm,P-K-AC以微孔为主,K-AC、P-AC均为介孔。3种活性炭表面均分布着丰富的含氧官能团和大量的无定型碳,为吸附MB提供了活性位点。在25 ℃条件下,将10 mg的P-AC、K-AC、P-K-AC分别加入50 mL质量浓度为100 mg/L的MB溶液中用于吸附MB实验。结果表明：P-K-AC的吸附效果最好,吸附率达到95%、吸附量为480.81 mg/g;其次是K-AC,吸附量为352.26 mg/g;P-AC吸附量最小,为225.01 mg/g。P-AC,K-AC、P-K-AC对MB的吸附过程都符合伪二级动力学模型、颗粒内扩散模型和Langmuir等温吸附模型。     

壳聚糖质活性炭对亚甲基蓝的吸附性能研究

用壳聚糖制成活性炭,研究其对亚甲基蓝的吸附能力,并分析了吸附动力学以及吸附等温线。结果显示,壳聚糖质活性炭对亚甲基蓝最佳的吸附条件为:投入量为0.3 g,吸附时间为60 min,亚甲基蓝体积为10 mL;吸附温度为50℃,吸附过程较为符合二级吸附动力学方程、Freundlich模型。     

一种生物质活性炭的制备及其对亚甲基蓝的吸附性能

以磷酸为活化剂,将稻壳、柚子皮分别与核桃壳按一定质量比混合,进行热解,制备了高吸附性能的生物质活性炭。研究结果表明:以柚子皮+核桃壳制备的生物质活性炭吸附亚甲基蓝2 h即可达平衡;比商品活性炭具有较优的吸附性能,对亚甲基蓝的吸附值达574.6 mg/g,吸附过程符合准二级动力学方程,等温吸附满足Langmuir等温吸附模型,属于自发进行的良性吸附。研究利用生物质废弃物,将其再利用并制备对染料吸附性能优良的生物质活性炭,可望成为环境友好型活性炭,并为生物质热解产物的资源化利用提供了应用前景。     

一种生物质活性炭的制备及其对亚甲基蓝的吸附性能

以磷酸为活化剂,将稻壳、柚子皮分别与核桃壳按一定质量比混合,进行热解,制备了高吸附性能的生物质活性炭。研究结果表明:以柚子皮+核桃壳制备的生物质活性炭吸附亚甲基蓝2 h即可达平衡;比商品活性炭具有较优的吸附性能,对亚甲基蓝的吸附值达574.6 mg/g,吸附过程符合准二级动力学方程,等温吸附满足Langmuir等温吸附模型,属于自发进行的良性吸附。研究利用生物质废弃物,将其再利用并制备对染料吸附性能优良的生物质活性炭,可望成为环境友好型活性炭,并为生物质热解产物的资源化利用提供了应用前景。     

山竹壳活性炭吸附亚甲基蓝性能研究

以山竹壳为原料,采用磷酸—硫酸活化法制备了比表面积为1730m~2·g~(-1)的活性炭。研究了山竹壳活性炭吸附亚甲基蓝的吸附性能,考察了亚甲基蓝溶液的pH、不同初始浓度、吸附时间、温度等条件对吸附效果的影响。应用准一级动力学方程、准二级动力学方程模拟了山竹壳活性炭吸附亚甲基蓝的动力学过程,结果表明准二级动力学方程适合描述整个吸附过程。用Langmuir和Freundlich模型模拟吸附等温线,Langmuir方程更适合描述此吸附过程,在298K下最大单层吸附量为526.31mg·g~(-1)。计算了吉布斯自由能(ΔG~0)、焓变(ΔH~0)、熵变(ΔS~0)等热力学参数,ΔG~0、ΔH~0、ΔS~0均小于0,说明此吸附过程是一个自发进行的、放热的、趋于有序的吸附过程。     

活性炭对水中亚甲基蓝的吸附性能研究

以活性炭为吸附剂,亚甲基蓝(MB)为吸附质,考察了吸附剂用量、吸附时间、温度对活性炭去除亚甲基蓝的影响。分别采用伪一级、伪二级动力学模型和Langmuir,Freundlich吸附等温线模型对吸附动力学和等温线进行分析。实验表明,在活性炭用量为0.667 g/L,吸附时间为360 min,反应温度为298 K时,活性炭对亚甲基蓝的最大吸附量为249.081 mg/g。吸附反应在前30 min内速率很快,并约在360 min内达到吸附平衡,吸附动力学符合伪二级动力学模型。吸附反应为放热反应,等温吸附过程符合Langmuir和Freundlich吸附等温模型,相关系数高于0.99。活性炭对去除水中亚甲基蓝效果好,是一种优良的吸附剂。     

茶渣活性炭的制备及其对亚甲基蓝的吸附性能研究

以茶渣作为原料,采用氢氧化钾活化法制备茶渣活性炭,探究了活性炭在不同条件下对亚甲基蓝的吸附性能。结果表明,茶渣活性炭具有多孔结构,表面含有含氧官能团,其比表面积为2 414 m²/g。将此活性炭应用于吸附亚甲基蓝,在40 mL浓度为200 mg/L的亚甲基蓝溶液中,活性炭添加量为4 mg,活性炭对亚甲基蓝的吸附量为1 488 mg/g。活性炭吸附亚甲基蓝的吸附模型符合Langmuir模型,动力学符合准二级动力学模型。茶渣活性炭对染料污染物有优异的吸附效果,在染料废水治理中有很大的应用前景。     

污泥活性炭的制备及对亚甲基蓝吸附性能研究

以城市污水处理厂的剩余污泥为原料,磷酸为污泥活化剂,采用微波加热法制备了污泥活性炭,考察了吸附剂投加量、吸附时间和p H对吸附效果的影响,并对其吸附动力学特性进行了探讨。结果表明:p H为8,投药量m为0.26 g,吸附时间为59 min,吸附温度为35℃,吸附浓度为58 mg/L时,污泥活性炭对亚甲基蓝的吸附效果最佳。污泥活性炭对亚甲基蓝的吸附满足Langmuir等温吸附方程。     

一步法制备富氧木质素活性炭及其亚甲基蓝吸附性能

以硫酸盐造纸黑液木质素为原料,分别采用磷酸活化和磷酸、硫酸混合酸活化制备了两类不同结构的木质素活性炭,对其进行了扫描电镜（SEM）、红外光谱（FTIR）、氮气吸附脱附、元素分析和Boehm酸值滴定等表征分析,并将制备的活性炭应用于模拟亚甲基蓝（MB）染料废水的吸附。结果表明,混合酸活化制备的木质素活性炭比单独磷酸活化的木质素活性炭的比表面积、总孔体积、介孔体积、氧含量分别增加了27.9%、26.4%、29.3%和29.2%,并且孔径分布更趋集中。混合酸活化活性炭在pH为2~9的范围内对亚甲基蓝均有优异的吸附性能,最大饱和吸附量达到1118.90 mg·g^-1,比磷酸活化木质素活性炭的吸附量增加了20.3%,表现出良好的吸附性能。吸附速率快,吸附过程遵循Langmuir等温线和伪二级动力学方程,颗粒内扩散不是唯一的决速步骤。     

木焦油基活性碳的制备及其对亚甲基蓝的吸附性能研究

木焦油是木质生物质材料的高温裂解产物。以木焦油为碳源,以甲醛化处理后的木焦油为前体,通过碳化-活化制备木焦油基活性碳材料。并以制备的木焦油基活性碳为吸附剂,研究了其对模拟水体中亚甲基蓝的吸附性能。结果表明,以木焦油为前驱体经高温碳化活化制备的多孔活性碳,比表面积可达1373Sm_²?g_^-1,表面含有丰富的含氧官能团。木焦油基活性碳对亚甲基蓝具有良好的吸附性能,准二级动力学模型能更准确的描述木焦油基活性碳吸附亚甲基蓝的动力学过程。吸附等温线更符合Langmuir等温吸附模型,木焦油基活性碳对亚甲基蓝的最大吸附容量可达559 mg?g_^-1。热力学分析表明亚甲基蓝在木焦油基活性碳上的吸附是放热和自发的。利用木焦油制备的活性碳材料对亚甲基蓝具有较高的吸附容量,是一种具有潜在应用前景的吸附材料。     

Activated carbons prepared from biogas residue: characterization and methylene blue adsorption capacity

BACKGROUND: In China, some biogas residue, which cannot be utilized by microbes in the anaerobic process, has been used as fertilizer. More has been deposited in biogas plants or on land around the plants. This has an effect on the environmental protection of the biogas plant, especially if the high lignin content in the biogas residue is not handled properly. RESULTS: In this study biogas residue has been used for the preparation of activated carbons by phosphoric acid activation. Textural characterization and feasibility of employing the prepared activated carbon to remove methylene blue (MB) from aqueous solution were investigated. The results show that the activated carbons have high surface area (1950 m² g^?1) and pore volume (1.232 cm³ g^?1). Equilibrium data were best described by the Langmuir isotherm model, with a maximum monolayer adsorption capacity of 344.83 mg g^?1 at 25 °C. Among the kinetic models studied, the pseudo‐first‐order model was found to be the most applicable to describe the adsorption of MB. CONCLUSIONS: The adsorption performance of activated carbons prepared from biogas residues (BR‐AC) was comparable with that of commercial material and other adsorbents reported in earlier studies and presents a high value added application for biogas residues. Copyright © 2010 Society of Chemical Industry     

An economically viable removal of methylene blue by adsorption on activated carbon prepared from rice husk

Application of an agricultural waste material, rice husk, has been investigated for preparation of activated carbon. The rice husk‐activated carbon (RHAC) was successfully utilised for the removal of a cationic dye, methylene blue (MB) from aqueous solutions. The activated carbon was prepared in presence of ZnCl₂ as an activating agent under inert nitrogen atmosphere. RHAC was characterised for surface area, pore structural parameters, and point zero charge (pH_ZPC). The activated carbon was further characterised by Fourier transformation infrared (FT‐IR) spectrometer, X‐ray diffractometer (XRD), and scanning electron microscope (SEM). The effect of different parameters such as contact time and initial concentration, adsorbent dose, and temperature on removal of the dye from aqueous solutions was investigated. The experimental data fitted well in both the Freundlich and Langmuir isotherm models. The maximum adsorption capacity for MB was found to be 9.73 mg g⁻¹ at 303 K. During the study of effect of adsorbent dose, almost a 100% removal was achieved at a higher dose of RHAC. Most of the experiments were carried out at an initial concentration of MB of 60 mg/L and at 303 K. Different thermodynamic parameters, viz., changes in free energy (G°), enthalpy (H°), and entropy (S°) have also been determined to explain feasibility of the process of removal. The sorption of MB on RHAC was found to be feasible, spontaneous, and endothermic in nature.     

微波改性活性炭深度处理亚甲基蓝染料废水的研究

为提高粒状活性炭(GAC)的吸附效果,采用微波技术对GAC改性处理,并对GAC和微波改性活性炭(W-GAC)进行表征分析。将COD去除率作为吸附效果的评价指标,以亚甲基蓝溶液作为处理对象,考察了GAC与W-GAC对其吸附性能。结果表明:W-GAC的比表面积与总孔容略有减小,表面酸性含氧基团含量明显减少,碱性基团含量上升。活性炭吸附亚甲基蓝废水的吸附等温线与Langmuir方程拟合较好。     

Microwave-assisted preparation of mesoporous-activated carbon from coconut (Cocos nucifera) leaf by H3PO4 activation for methylene blue adsorption

Mesoporous-activated carbon was prepared from fallen coconut (Cocos nucifera) leaf, an agricultural waste through a microwave-induced H₃PO₄ activation process. The characterization of the coconut leaf–activated carbon (CAC) was evaluated through the iodine number, ash content, bulk density, and moisture content. Fourier transform infrared spectroscopy, scanning electron microscope, Brunauer–Emmett–Teller (BET) surface area, X-ray diffraction, and pH_PZC. CAC has a mesopore content of 84% with an average pore size of 36.5?Å and a large BET surface area of 632?m²/g. The uptake properties of the CAC with methylene blue was evaluated at different CAC dosage levels (0.2–10?g/L), initial pH (3–10), methylene blue concentration (50–350?mg/L), and time (0–360?min) using batch mode operation. The kinetic profiles were described by the pseudo-second-order kinetics. The equilibrium data were well fitted to the Langmuir model with a maximum monolayer adsorption capacity of 250?mg/g at 30°C. Thermodynamic functions indicate a spontaneous and exothermic nature of the adsorption process. This study indicates that coconut leaves are a promising renewable precursor that can be utilized to develop an efficient mesoporous-activated carbon.     

微波诱导活性炭纤维氧化处理亚甲基蓝废水

以活性炭纤维为催化剂,采用微波诱导氧化工艺处理亚甲基蓝废水,考察了活性炭纤维用量、微波辐射时间、溶液浓度、pH值、盐含量、过氧化氢加入量等因素对处理效果的影响。结果表明,0.05 g活性炭纤维与400 mg/L 25 mL废水混合,在微波功率1 000 W,辐射时间120 s的条件下,亚甲基蓝的去除率达到98.2%,pH、盐和过氧化氢加入量对处理效果有不同的影响。微波诱导氧化、活性炭纤维吸附、单独微波辐射和沸水浴加热四种不同工艺的对比实验表明,微波诱导氧化工艺具有明显的优越性,不会对环境造成二次污染,机理是通过吸附和高温氧化协同作用。氧化动力学过程符合一级反应规律。活性炭纤维催化活性随着使用时间增加而减弱,连续使用29 min,催化能力几乎消失。     

软锰矿-含油污泥基活性炭对亚甲基蓝的吸附特性

以含油污泥为原料,添加适量软锰矿制备活性炭,用于吸附水中的亚甲基蓝并探究其吸附性能与吸附机制。采用SEM、BET、XPS、FTIR表征活性炭的微观形貌和物相结构,利用二维红外相关光谱探究活性炭与亚甲基蓝的吸附点位及吸附机制。结果表明,活性炭是比表面积达464.409m²/g的介孔材料,且表面含有大量的含氧官能团,活性炭吸附亚甲基蓝的过程符合准二级动力学方程和Langmuir模型,主要受化学吸附控制的单分子层吸附。结合移动窗口二维红外相关光谱分析发现,在活性炭吸附亚甲基蓝的过程中吸附较低浓度的亚甲基蓝参与的官能团较多,以各种含氧官能团为主,当亚甲基蓝浓度升高,以π-π相互作用为主;吸附机制包括氢键作用、含氧官能团参与和π-π相互作用等。