数学方法在活性炭对亚甲基蓝脱色力测定中的应用

GB/T1 2 4 96.2 - 1 990标准提供的活性炭对亚甲基蓝脱色力的测定法 ,是将一定体积的亚甲基蓝溶液 (在波长 665nm处用 1 cm比色皿进行测定吸光度为 0 .35)加到 0 .1 0 0 g活性炭中 ,经充分振荡 ,过滤后 ,仍然用 1 cm比色皿在波长 665nm处 ,测定滤液的吸光度 ,当其值在 0 .0 4～ 0 .0 7时 ,亚甲基蓝溶液的加入量 ,即为测得的活性炭对亚甲基蓝的脱色力。由于这一测定方法的特殊性 ,通常需做多次试验 ,才能恰好使滤液的吸光度落在 0 .0 4～ 0 .0 7,给日常分析工作带来了很大的不便 ,本文利用数学方法 ,提出了一种较为简单的测定方法。1　原理…     

活性炭脱色对食醋总酸量的影响

研究活性炭脱色对食醋总酸量的影响。以保宁醋稀释10倍为供试品工作液,利用酸碱滴定法采用酸碱指示剂和酸度计同时监测溶液pH的变化确定终点,通过消耗NaOH体积反映对总酸量的影响,监测在450 nm处吸光度的变化反应脱色效果,研究了加入不同活性炭用量和脱色时间对食醋总酸量和脱色效果的影响,同时研究了活性炭脱色对食醋中可能有的几种无色有机酸的酸量的影响。结果表明：只要用活性炭脱色,测定食醋的总酸量总是偏低,活性炭脱色对几种无色有机酸的酸量有不同程度的影响。不能用活性炭脱色后,用指示剂确定终点酸碱滴定法测定食醋的总酸量。     

花生壳活性炭的制备及其对亚甲基蓝吸附效果研究

在无N2条件下,以农业废弃物花生壳为材料,分别以氯化锌和碳酸钾为活化剂制备活性炭。通过正交试验以亚甲级蓝的吸附为考察对象,获得最优工艺条件。通过扫描电镜观测活性炭表面形貌并研究各因素吸附效果的影响,与市售活性碳对比。氯化锌活性炭最优工艺条件:浸渍温度90℃、浸渍时间12 h、物料比1∶2、活化温度650℃、活化时间60 min。碳酸钾活性炭最优工艺条件:浸渍温度120℃、浸渍时间6 h、物料比1∶2、活化温度650℃、活化时间100 min。扫描电镜观测结果表明,活性炭表面均形成了丰富的1μm左右的孔状结构,并且以ZnCl2为活化剂的活性炭形成部分超大孔径,造成表面有少量的坍塌结构。自制的两种最优活性炭的吸附量均大于商业活性炭,同时自制活性炭吸附平衡时间更短,可以使用的温度范围更宽。     

血宝中硫酸亚铁的比色测定

利用Fe^2 与邻二氮菲生成红色络合物的原理，用比色法测定了血宝中硫酸亚铁的含量，由于血宝本身带有颜色，笔者采用活性炭进行脱色处理，效果很好，并对其它实验条件作了探讨，结果准确，方法简便，可作为血宝的质量控制方法，加以推广运用。     

葡萄酒中微量高锰酸钾含量的测定

利用碱性氧化铝对葡萄酒脱色后,用分光光度法对其中高锰酸钾含量进行测定。在30℃、pH=8.5条件下,用4.0 g碱性氧化铝对20 m L样品进行振荡脱色2 h,脱色率可以达到95%以上,此法的测定准确度较高。     

超临界甲烷在活性炭上的吸附平衡分析

为分析由吸附平衡时的热力参数确定吸附量、吸附模型和等量吸附热精度的影响因素,选择在温度268.15~338.15 K和压力0~13.5 MPa测试的甲烷在Ajax活性炭上的吸附平衡数据,通过引入甲烷分子可进入活性炭吸附空间内的容积和可以不考虑甲烷在孔内吸附的临界孔宽的概念,依据甲烷在吸附平衡前后的总量守恒,确定甲烷在吸附池内的总量、绝对吸附量和过剩吸附量三者之间的关系式。结果表明,在引入吸附质分子可进入吸附空间内的容积和临界孔宽后,经由活性炭的孔径分布(PSD),可以准确计算甲烷在活性炭上的过剩吸附量;应用实验数据非线性回归Toth方程参数后,可由Gibbs关于吸附的定义确定甲烷在活性炭上的绝对吸附量。比较结果时发现,由于未考虑本体相中甲烷分子对吸附甲烷分子的影响,采用过剩吸附量的等量吸附线标绘确定的等量吸附热数值偏高,工程应用时应由绝对吸附量来确定等量吸附热。     

川芎多糖脱色方法比较

比较了活性炭、H2O2和大孔吸附树脂对川芎多糖提取液的脱色效果。选用极性大孔树脂S-8在工作液流速为2BV/h,川芎浓度为0.33g/mL时,脱色率为92.7%,多糖保留率为93.0%,表明S-8适合用于川芎多糖提取液脱色。     

甘氨酸母液脱色活性炭的微波法再生研究

脱色甘氨酸母液的废活性炭,是一类吸附有有机胺类聚合物且难以再生的危险固体废弃物。本文探索性地开展了微波法再生脱色甘氨酸母液废活性炭的研究,考察了活性炭在微波炉中的放置方式、含水率以及微波反应条件等对活性炭再生率和炭损率的影响,分别采用红外光谱法、BET法对活性炭进行了分析表征。实验结果表明,在功率640 W、反应时间8 min的条件下,废活性炭的再生率达99%、综合再生率达59.0%,对再生活性碳进行红外光谱分析表明,在微波功率大于480 W后,微波辐射能有效去除废活性炭中的有机物;在微波功率800W条件下,再生活性炭的BET比表面积由废活性炭的128.15 m2/g提高到1398.5437 m2/g,已达到新鲜活性炭的性能。     

复合型高效絮凝脱色剂处理印染废水的研究

选用自制的双氰胺甲醛作为絮凝脱色剂处理高浓度印染废水,并与硫酸铝、三氯化铝作了对比实验。考察了投加量、pH值、反应温度等因素对絮凝效果的影响。实验结果表明在用量较少并且其它操作条件相同的情况下,双氰胺甲醛制备的脱色絮凝剂具有很好的絮凝脱色效果及COD_(Cr)去除率。在最佳的操作条件下(投加量120 mg/L,pH=7,反应温度25℃),此脱色絮凝剂对分散、酸性、活性印染废水的COD_(Cr)去除率分别为79.1%、78.5%、79.0%,对分散、酸性、活性印染废水的脱色率分别为94.0%、97.1%、72.9%,减轻了后续处理难度。在与无机絮凝剂的对比试验中,在相同的条件下有机絮凝剂的处理效果总体比无机絮凝剂的处理效果好。     

活性炭催化碳酸二甲酯水解行为的研究

以无氯Cu/AC催化剂中活性炭载体为研究对象,对活性炭上DMC水解反应条件进行了考察,并通过Boehm滴定法和XPS对活性炭上DMC水解活性位点进行了分析。结果表明,温度的升高和水含量的增加对DMC水解有较大的促进作用,较高的压力和CO₂气氛对DMC水解有一定的抑制作用,甲醇量和CO、O₂、N₂气氛对DMC水解影响较小。不同条件处理的活性炭表面基团种类、数量均有较大变化,HNO₃处理使活性炭碱性基团含量下降,羧基等酸性含氧官能团含量明显增加,总酸量最高可达1.88 mmol·g^-1;先HNO₃后NaOH处理的活性炭上酸性基团含量大量减少,表面碱性基团含量则有较大提高,总碱量最高可达1.69 mmol·g^-1。特别地,活性炭表面碱性基团是催化DMC水解的活性位点,在活性炭碱性基团含量由0.16增加到1.69 mmol·g^-1的过程中,DMC水解程度由2.5%增加到了31.7%,而酸处理可以有效降低活性炭表面碱性基团含量,抑制其催化DMC的水解性能。     

多孔炭材料的研究进展及前景

近年来多孔炭材料在国内外的研究和开发应用都十分活跃。本文从制备原料的扩展, 形态特征的增多, 纳米空间的控制, 功能特性的改进, 微细组织的察, 应用途径的开拓等不同方面综述了多孔炭材料的研究和应用开发的新进展。     

A Novel High Active TiO2/AC Composite Photocatalyst Prepared by Acid Catalyzed Hydrothermal Method

A high active novel TiO2/AC composite photocatalyst was prepared and used for phenol degradation. It was much more active than P-25 and exhibiting good decantability, less deactivation after several runs and less sensitive to pH change. Diffuse reflectance spectra (DRS) revealed that the electronic change in TiO2 did not occur by the addition of AC. Results of SEM and XRD suggested that better TiO2 distribution can be achieved when optimal AC content was adopted. The performance of the prepared TiO2/5AC catalyst revealed great practical potential in wastewater treatment field.     

活性炭对乙二醛溶液的脱色研究

乙二醛是一种重要的化工产品和医药中间体,在纺织印染、建材、皮革、医药、农药、国防、涂料、轻工、粘合剂、石油、冶金、环保等方面具有广泛的用途[1,2]。其工业生产方法主要有乙醛硝酸氧化法和乙醇气相氧化法[3~6]。两种方法制得的乙二醛溶液在纯化过程中,溶液颜色加深,不能     

粉末活性炭基复合材料制备及净化含油污水的性能和机制

针对粉末活性炭对亲水小分子有机物吸附效率低和固液分离速度慢的问题, 本研究以粉末活性炭(PAC)、腐植酸盐(HS)、聚合氯化铝(PACl)为原料, 通过融合法成功制备了粉末活性炭基复合材料PACMC (powdered activated carbon matrix composites), 将其作为含油污水的净化吸附剂. 扫描电子显微镜-X射线能量色散谱仪(SEM-EDS)和傅里叶红外光谱(FT-IR)等表征分析确认了PACMC的微观形貌和化学组成, 证实了PAC、HS和PACl是通过化学反应生成了PACMC. PACMC具有层状多孔结构和活性官能团, 有利于含油污水分子的传输扩散和化学吸附. 通过静态吸附实验研究了PACl、PAC和PACMC对含油污水中有机物的吸附性能, 结果表明: PACMC对含油污水中有机污染物的吸附能力是PAC和PACl的2~3倍(q_e=23.04 mg•g^‒1, C₀=300 mg•L^‒1); 当吸附时间达到120 min 时, PACMC上的活性位点与含油污水中有机污染物的结合已基本达到饱和(q_e=23.04 mg•g^‒1, C₀=300 mg•L^‒1). 溶液pH值对PACMC吸附去除含油污水中有机物的影响显著, pH=3时, 吸附效果最好(q_e=27.6 mg•g^‒1, C₀=300 mg•L^‒1); 伪二级动力学方程能很好地描述含油污水中有机物在PACMC上的吸附行为, 动力学拟合结果表明其吸附过程分多步进行, 化学吸附和内扩散均具有重要作用. 等温吸附数据符合Dubinin-Radushkevich模型, 证明其吸附机理为化学吸附. 因此, PACMC吸附含油污水的机理包括化学结合/螯合作用、疏水力作用和静电吸附作用.     

Adsorbents from Waste materials

The possibility of using pyrolyzed wastes produced in already working incineration plants, as adsorbents for waste water treatment, was studied. Showing very poor adsorption properties, they were improved by steam activation technique used in the conventional activated carbon manufacturing. It is concluded that various organic waste materials can be converted to carbonaceous final products with a character similar to activated carbon. Their adsorption properties and pore size distribution are determined by the structure of the starting material. Although most of these samples have a low specific surface area, their pore volume is not negligible in the meso-and micropore range. Adsorption tests with model waste waters confirmed that adsorption properties are strongly influenced by the character of the suface. The adsorption capacity of these samples can be utilized for the treatment of strongly polluted industrial waste waters. Considering that the raw material ‘needed’ to manufacture these adsorbent is produced permanently and the adsorbents do not have to be regenerated, it might be worthwhile using these kinds of adsorbents in the primary treatment of industrial waste waters.     

萃取温度对无灰煤结构及煤基活性炭电化学性能的影响

以内蒙古褐煤为原料,N-甲基吡咯烷酮为萃取剂,在不同温度下萃取制备无灰煤,进而利用KOH活化法制备活性炭,探究萃取温度对活性炭电化学性能的影响。结果表明,无灰煤萃取温度对煤基活性炭电化学性能有显著影响。对无灰煤及原料褐煤的灰分含量,表面官能团含量和对应活性炭的比表面积、孔结构及其电化学性能进行对比发现,330℃下萃取制备出的无灰煤在碱煤质量比3∶1,活化温度650℃,活化时间2h的活化过程中具备最适宜的反应性,对应活性炭比表面积高达1 252 m~2·g~(-1),表面官能团含量适中,在3 mol·L~(-1)KOH电解液中50 mA·g~(-1)电流密度下比电容高达322 F·g~(-1),2 A·g~(-1)的电流密度下比电容保持率仍可接近90%。     

Activated carbon membrane for water treatments: Application to decolorization of coke furnace wastewater

An activated carbon membrane to be used in water treatments was developed and the decolorization of the coke furnace wastewater was successfully demonstrated as a model case. The activated carbon membrane was prepared by carbonizing poly-vinydenchloride (PVdC) and poly-vinylalcohol (PVA) microspheres aggregating on and within a ceramic pipe. The membrane developed in this work was suspected to have a bidispersed structure, which made it possible to play the roles of both a porous membrane having the molecular weight cut-off of about 10,000 and an activated carbon bed where the dissolved organics with low molecular weight could be adsorbed. The activated carbon membrane developed in this work appears to be useful for compact water treatment processes.     

Structural Characterization and Property Study on the Activated Alumina-activated Carbon Composite Material

AlCl3,NH3·H2O,HNO3 and activated carbon were used as raw materials to prepare one new type of activated alumina-activated carbon composite material.The influence of heat treatment conditions on the structure and property of this material was discussed;The microstructures of the composite material were characterized by XRD,SEM,BET techniques;and its formaldehyde adsorption characteristic was also tested.The results showed that the optimal heat treatment temperature of the activated alumina-activated carbon composite material was 450 ℃,iodine adsorption value was 441.40 mg/g,compressive strength was 44 N,specific surface area was 360.07 m2/g,average pore size was 2.91 nm,and pore volume was 0.26 m3/g.According to the BET pore size distribution diagram,the composite material has dual-pore size distribution structure,the micro-pore distributes in the range of 0.6-1.7 nm,and the meso-pore in the range of 3.0-8.0 nm.The formaldehyde adsorption effect of the activated alumina-activated carbon composite material was excellent,much better than that of the pure activated carbon or activated alumina,and its saturated adsorption capacity was 284.19 mg/g.     

KOH活化木屑生物炭制备活性炭及其表征

以木屑热裂解的生物质炭为原料,氢氧化钾为活化剂,采用化学活化法制备活性炭,探讨了碱炭比、活化温度和活化时间对活性炭吸附亚甲基蓝吸附值的影响。 利用N2吸附实验、XRD和FTIR等实验技术,对原料与制备活性炭的结构与性能进行了表征。 结果表明,在碱炭质量比为1.5、活化温度750 ℃、活化时间2 h的条件下,所制备的活性炭对亚甲基蓝吸附值为255 mg/g,BET总比表面积为1514 m2/g,中孔比表面积为110 m2/g,吸附总孔容为0.821 cm3/g,中孔孔容为0.117 cm3/g,吸附平均孔径为2.170 nm。