改性吸附剂脱除燃油中二苯并噻吩的研究

采用浸渍法将5种金属离子Zn2+,Cu2+,Fe3+,Pb2+,Hg2+负载于活性炭和γ-氧化铝上,制备出一系列改性的吸附剂;用静态吸附法测定了燃料油中二苯并噻吩在不同吸附剂上的吸附等温曲线。结果表明,活性炭对97#汽油中二苯并噻吩吸附能力显著高于氧化铝;活性炭表面负载Zn2+,Cu2+,Fe3+,可以提高其对97#汽油中的二苯并噻吩的吸附量(摩尔质量浓度),其中负载Zn2+的活性炭吸附能力最大,硫饱和吸附量为478.3mmol/kg;γ-氧化铝上Pb2+的最佳负载质量分数为5.0%。     

稻壳吸附剂的制备及其吸附聚丙烯酰胺的应用研究

采用稻壳为原料,使用浓硫酸炭化活化稻壳方法制备稻壳活性炭。将所制备的活性炭吸附处理聚丙烯酰胺污水,确定了活性炭最佳吸附能力的制备工艺条件,并通过一系列实验得出了稻壳吸附剂吸附溶液中HPAM的最佳实验条件,并深入研究了其吸附处理HPAM过程的吸附动力学,确定了其等温吸附线模型。实验结果表明,采用浓硫酸处理稻壳的方法制备活性炭具有方法简单、处理效果好的特点,因此在含聚污水的前期预处理中具有良好的应用前景。     

Cu（Ⅰ）-13X吸附噻吩/苯并噻吩的动态性能

采用液相离子交换法制备Cu（Ⅰ）-13X分子筛,进行噻吩（T）、苯并噻吩（BT）双组分的固定床动态吸附研究,考察模拟汽油原料中噻吩与苯并噻吩初始质量分数、床层停留时间、床层高度等条件对床层净化效果的影响.结果表明：随着模拟汽油原料中噻吩初始质量分数的增大,吸附剂饱和吸附容量增大,原料中噻吩初始质量分数为1 000μg/g时的吸附剂吸附容量比噻吩初始质量分数800μg/g时提高7.2%,增大原料中噻吩的初始质量分数,有利于苯并噻吩的脱除;床层停留时间较长有利于固定床吸附,停留时间由24 min增加至30 min时,吸附总容量增加19.2%,噻吩、苯并噻吩的饱和吸附量分别增加26.5%和25.5%;床层高度由16 cm增加至20 cm时,吸附剂饱和吸附容量增加8.9%,噻吩、苯并噻吩的饱和吸附量分别增加15.3%和6.6%.     

稻壳炭脱硅制活性炭及吸附性能研究

研究稻壳炭脱硅工艺,探究氯化锌法和磷酸法活化脱硅稻壳炭工艺。结果表明,通过热碱溶解回流有很好的脱硅效果。磷酸活化法制备稻壳活性炭相对氯化锌活化法而言,得率较高,在浸渍比为2∶1,浓硫酸添加量为1%,预处理温度240℃,预处理时间1 h,活化温度500℃的实验条件下制得的活性炭,亚甲基蓝吸附值66 mg/g,碘吸附值679 mg/g。实验表明该工艺制得的活性炭不仅吸附性能较好且产量高,在工业应用上具有很好的经济价值。     

磷酸浸渍法制备生物质活性炭吸附氨气

本文研究了磷酸浸渍棕榈壳制备的活性炭用于吸附NH_3。考察了活化温度、H_3PO_4浓度和浸渍时间对活性炭比表面积的影响。本活性炭的氨吸附量不仅仅取决于吸附剂的比表面积,不同于蒸汽法制备的活性炭。在宽温环境下的吸附和解吸实验证明同时发生了物理吸附和化学吸附。化学吸附所导致的氨吸附量与吸附剂表面的氧含量密切相关,化学吸附是由于氨和活性炭表面的一些含氧官能团通过氢键作用而产生的。在此基础上,探讨了磷酸浸渍和化学吸附过程的机理。     

磷酸活化法制备花生壳活性炭工艺

采用正交试验方法探讨了以花生壳为原料,通过磷酸活化法制备的高效活性炭吸附剂。以活性炭的收率和Pb2+吸附容量为考察指标,选择了磷酸质量浓度、浸渍质量比和活化温度3个因素,3个水平的正交试验方法。结果表明,对活性炭收率影响最大的因素是活化温度,对活性炭吸附Pb2+容量影响最大的是磷酸活化剂的质量浓度。综合考察各影响因素,得出在磷酸活化剂质量浓度为1 220 kg/m3,浸渍质量比为150%和活化温度为400℃时可以在保持活性炭收率较高的情况下制备高Pb2+吸附容量的花生壳活性炭吸附剂,该活性炭的比表面为1 018.5 m2/g,总孔容积为0.754 m3/g,平均孔径为2.961 nm,对低质量浓度含铅废水中铅离子的去除率接近100%,是合适的液相吸附用活性炭材料。     

改性活性炭脱除模拟烟气中气态汞的实验研究

以椰壳活性炭为原料,经硝酸活化再采用NaCl或NaBr溶液化学浸渍改性制备燃煤烟气脱汞吸附剂。通过N_2吸附-脱附(BET),扫描电子显微镜(SEM),X射线光电子能谱(XPS)对制备的吸附剂进行表征,并且采用模拟烟气在管道喷射装置内考察汞吸附脱除性能。结果表明:与原始椰壳活性炭相比,经硝酸活化后的椰壳活性炭汞吸附能力得到提高;而采用NaBr改性后的椰壳活性炭脱汞效果最好。在管道喷射实验装置内,经过1 mol/L NaBr改性后的椰壳活性炭,在模拟烟气温度120℃,碳汞质量比8 000,停留时间2 s条件下,脱汞率达到92.7%。改性后的椰壳活性炭是一种具有潜在应用价值的优良脱汞吸附剂。     

磷酸活化法活性炭的吸附性能和孔结构特性

采用磷酸活化法在不同操作条件下制备得到各种活性炭,实验测定了相应活性炭的亚甲蓝吸附值、氮气吸附等温线及活性炭的比表面积和孔容。分别研究了磷酸活化法制备活性炭的主要操作参数,如浸渍比、活化时间和活化温度对活性炭吸附性能和活性炭的孔结构特征的影响。实验结果表明,浸渍比是磷酸活化法制备活性炭的最重要的影响因素。综合考虑活性炭的吸附性能和孔结构特征受活化操作参数的影响规律,探讨了磷酸活化法生产木质活性炭的最优操作参数。在实验范围内,磷酸活化法制备木质活性炭的最优操作条件宜选择浸渍比为100％～150％、500℃左右活化温度和60～90min的活化时间。     

载铜活性炭对CO的吸附作用

本研究用两种铜盐的酸性水溶液分别浸渍活怀炭制备了ＣＯ吸附剂，考察了载体、铜盐和活化过程对所制备的吸附剂吸附ＣＯ性能的影响。结果表明：浸渍、蒸发溶剂后，在２００℃、减压条件下活化载铜活性炭１ｈ，可以得到性能较好的ＣＯ吸附剂；吸附剂中起吸附ＣＯ作用的是Ｃｕ＾＋１，适当增加铜盐含亘并选用细粒果壳活性炭可以改善吸附剂的性能。     

超声对Cu(I)/SBA-15脱硫吸附剂制备和性能的影响

分别采用超声浸渍法和普通浸渍法制备了Cu(I)/SBA-15吸附剂,利用静态吸附实验比较了这两种方法制备的吸附剂在模型汽油中的噻吩吸附脱硫性能,并利用BET,TEM,XPS等手段对所制备的吸附剂进行了表征.结果表明,超声浸渍法制备的Cu(I)/SBA-15吸附剂的脱硫性能明显优于普通浸渍法制备的吸附剂.BET结果显示,超声促进了活性组分铜在吸附剂表面的分散.TEM分析表明,在超声场下制备的Cu(I)/SBA-15吸附剂表面的铜粒子颗粒较小,且分布均匀.XPS分析显示,超声有效地提高了铜离子在吸附剂表面的负载量,并且促进Cu(I)在其表面含量的增加,从而有利于吸附脱硫性能的提高.     

Ultra-deep desulfurization and denitrogenation of diesel fuel by selective adsorption over three different adsorbents: A study on adsorptive selectivity and mechanism

Adsorptive desulfurization and denitrogenation were studied using a model diesel fuel, which contains sulfur, nitrogen and aromatic compounds, over three typical adsorbents (activated carbon, activated alumina and nickel-based adsorbent) in a fixed-bed adsorption system. The adsorptive capacity and selectivity for the various compounds were examined and compared on the basis of the breakthrough curves. The electronic properties of the adsorbates were calculated by a semi-empirical quantum chemical method and compared with their adsorption selectivity. Different adsorptive selectivities in correlation with the electronic properties of the compounds provided new insight into the fundamental understanding of the adsorption mechanism over different adsorbents. For the supported nickel adsorbent, the direct interaction between the heteroatom in the adsorbates and the surface nickel plays an important role. The adsorption selectivity on the activated alumina depends dominantly on the molecular electrostatic potential and the acidic–basic interaction. The activated carbon shows higher adsorptive capacity and selectivity for both sulfur and nitrogen compounds, especially for the sulfur compounds with methyl substituents, such as 4,6-methyldibenzothiophene. Hydrogen bond interaction might play an important role in adsorptive desulfurization and denitrogenation over the activated carbon. Different adsorbents may be suitable for separating different sulfur compounds from different hydrocarbon streams.     

The adsorption of dibenzothiophene using activated carbon loaded with cerium

Cerium-loaded activated carbon was prepared by classical soaking impregnation method and tested for dibenzothiophene adsorption from model fuels. The new adsorbents showed much better adsorption capacity and selectivity towards DBT than the virgin carbon. The adsorbents were characterized by N₂ adsorption, Boehm titration and FTIR. The improved performance is mainly due to changes in surface chemistry. The results show that the performance of activated carbon as desulfurization adsorbents can be considerably enhanced by a simple cerium loading method.     

载体对负载型CuCl吸附脱硫剂性能的影响

采用等体积浸渍-焙烧自还原法制备系列以氯化亚铜为活性组分的负载型吸附脱硫剂,载体分别为氧化铝、不同孔径硅胶、13X分子筛和活性炭。对不同种类硫化物进行吸附实验,利用微库仑滴定仪对吸附后的溶液测试。结果表明,载体类型对吸附剂脱硫效果影响明显,而且不同硫化物的吸附硫容有较大差别,氧化铝吸附剂有较好的脱硫效果。     

Cu-ACFS深度脱硫吸附剂的制备与性能

采用浸渍法制备了活性碳纤维（ACFS）负载CuCl的深度脱硫吸附剂Cu-ACFS。在常温常压下,研究了吸附剂对汽油模型溶液中噻吩硫的静态吸附脱硫性能,并优化了吸附剂的制备条件。结果表明,吸附剂的CuCl负载量随浸渍时间的延长刚开始增加很快,到24h以后趋于平衡,吸附剂的脱硫率随着吸附剂中CuCl负载量的增加而增加,最高可达到89．29％,Cu（I）在ACFS上的最优负载量为49．5962mg／g,对应吸附剂的硫吸附量为11．7074mg/g,处理后模型溶液的硫含量由179×10^-6降低到30×10^-6以下,且吸附剂的再生性能良好。     

Cu-ACFS深度脱硫吸附剂的制备与性能

采用浸渍法制备了活性碳纤维(ACFS)负载CuC l的深度脱硫吸附剂Cu-ACFS。在常温常压下,研究了吸附剂对汽油模型溶液中噻吩硫的静态吸附脱硫性能,并优化了吸附剂的制备条件。结果表明,吸附剂的CuC l负载量随浸渍时间的延长刚开始增加很快,到24 h以后趋于平衡,吸附剂的脱硫率随着吸附剂中CuC l负载量的增加而增加,最高可达到89.29%,CuⅠ()在ACFS上的最优负载量为49.596 2 mg/g,对应吸附剂的硫吸附量为11.707 4 mg/g,处理后模型溶液的硫含量由179×10-6降低到30×10-6以下,且吸附剂的再生性能良好。     

Energy-efficient ultra-deep desulfurization of kerosene based on selective photooxidation and adsorption

Selective photooxidation and adsorptive desulfurization of kerosene was investigated for fuel cell applications. Photooxidation was conducted using a 5 W low-pressure mercury lamp at 25 °C in the presence of O₂. It was found for the first time that the rates of photooxidation of dominant sulfur compounds remaining in commercial kerosene after hydrogenation were at least 100 times higher than those of benzothiophenes (BTs) and dibenzothiophenes (DBTs), although their molecular forms were not clarified. The photooxidation of these highly reactive sulfur compounds was completed within 30 min and made them removable by adsorbents such as molecular sieves. On the other hand, non-reactive sulfur compounds such as DBTs were removed by adsorbents such as activated carbon. Using this proposed method, which combines selective photooxidation of highly reactive sulfur compounds and adsorptive desulfurization of reactive and non-reactive sulfur compounds, the total sulfur content in kerosene can be efficiently reduced to less than 0.1 μg g⁻¹ (ppm) under mild conditions.     

稻壳生物质资源利用技术研究进展

稻壳是一种产量巨大的农业废弃物,直接丢弃或掩埋不但会造成资源浪费更会引起环境污染。稻壳中含有丰富的SiO₂、纤维素、半纤维素和木质素等。资源化利用是稻壳有效利用的发展方向和趋势。本文综述了近年来国内外稻壳资源化利用的研究进展。根据稻壳的特性,将资源化利用方式分为能源化利用、工业化利用及农业化利用,并对其研究现状进行了介绍。重点阐述了稻壳在气化制备可燃气、热裂解制备生物油、改性制备吸附剂、合成分子筛、制备催化剂载体、生产白炭黑与活性炭、水解制备糠醛、木聚糖、低聚木糖及发酵制备饲料等方面的研究进展,同时对其发展方向和趋势进行了展望,指出最大限度控制成本将成为稻壳资源化利用实现工业化的重要因素。     

流化催化裂化汽油吸附脱硫金属氧化物吸附剂

制备了不同的金属氧化物吸附剂并采用不同方法进行改性,在常压、温度为360℃、液时空速为1 h-1的条件下,采用固定床吸附法考察了吸附剂改性前后的脱硫性能.结果表明:MoO3和MnO2的脱硫效果较好,对硫含量为511.10 μg/g的流化催化裂化(FCC)汽油脱硫,脱硫率达60%以上;CuO-MoO3,MoO3-MgO和MoO3-Fe2O3复合金属氧化物吸附剂对FCC汽油的脱硫效果可达75%以上,其中脱除乙硫醇效果最好的是CuO-MoO3,脱除噻吩效果最好的是MoO3-MgO,脱除二苯并噻吩效果最好的是MoO3-Fe2O3;采用等体积浸渍法对MoO3和MnO2改性后,对FCC汽油吸附脱硫效果有所增强,其中对MoO3改性效果较好的是NiO,脱硫率可达90.1%,对MnO2改性效果较好的是CoO,脱硫率可达93.2%.     

负载型氧化锌脱硫剂的实验研究

采用浸渍法制备了以γ-Al2O3为载体的负载型氧化锌脱硫剂,同时对制得的脱硫剂进行煤气脱硫实验,考察了制备过程中负载量、焙烧温度和硫化温度等对脱硫剂性能的影响,用XRD和BET方法对制得的脱硫剂进行检测.结果表明,制得的脱硫剂存在一个单层分散当量,当负载量低于单层分散当量时,ZnO将以单层或亚单层状态分散在载体γ-Al2O3上(XRD检测不到);当高于负载量时,除了单层或亚单层以外,ZnO晶体也将出现,通过XRD衍射图谱可以观察到ZnO晶体的衍射峰.活性评价实验也表明,在低于单层分散当量时该脱硫剂的穿透硫容随着负载量的增加而增大,且在极高的脱硫精度下(低于0.1×10-6)有较高的活性ZnO穿透硫容,达到了9.7 g S/100 g ZnO;而高于单层分散阈值时稳定性和硫容明显降低.     

Preparation of powdered activated carbon from rice husk and its methane adsorption properties

Success of adsorbed natural gas (ANG) storage process is mainly based on the characteristics of the adsorbent, so various synthesized adsorbents were analyzed for methane adsorption on a thermodynamic basis. Activated carbon from rice husk (AC-RH) was synthesized and its methane adsorption capacities were compared with phenol based activated carbons (AC-PH₂O and AC-PKOH). The adsorption experiments were conducted by volumetric method under various constant temperatures (293.15, 303.15, 313.15 and 323.15 K) and pressure up to 3.5MPa. Maximum methane adsorption was observed in AC-RH as its surface area is higher than the other two adsorbents. The experimental data were correlated well with Langmuir-Fruendlich isotherms. In addition, isosteric heat of adsorption was calculated by using Clausius-Clapeyron equation.