柑橘皮对重金属生物吸附的研究进展

重金属污染物在环境中十分稳定,并且具有相当高的难去除性,对人类的生命和健康造成直接或间接的危害。生物吸附法是一种很有潜力的新兴重金属去除技术,也是一种有效、可行、环境友好的方法,对污水处理具有重大意义。柑橘皮价格低廉,去除重金属效果好,易于得到,成本低,并且具有技术可行性,工业化实用性以及对生物吸附剂再生和金属回收的可能性,因此其具有广阔的应用前景。综述了利用柑橘皮作为吸附剂处理重金属离子的研究现状、吸附机理和影响吸附剂的吸附因素,并对其发展前景作了展望。     

Removal of copper(II) from aqueous solution using chemically modified fruit peels as efficient low-cost biosorbents

Fruit peels, which are common agricultural byproducts, have been extensively used as abandoned or low-cost biosorbents to remove heavy metals. In this study, dragon fruit peel (DFP), rambutan peel (RP), and passion fruit peel (PFP) were used to remove Cu(II) ions from an aqueous solution. Concentrations of the adsorbed metal ions were determined using the atomic absorption spectroscopic method. Adsorption experiments were performed with different adsorbent dosages, pH values, contact times, and initial copper concentrations. The optimum set of conditions for biosorption of Cu(II) ions was found to be an adsorbent dosage of 0.25 g, a contact time of 180 min, an initial concentration of 100 mg/L, a pH value of 4 for RP and PFP, and a pH value of 5 for DFP. The adsorption conformed with the pseudo-second-order kinetic model. The adsorption data were consistent with the Langmuir and Freundlich isotherm models, but the best fit was with the Langmuir model. The Langmuir monolayer adsorption capacity values of DFP, RP, and PFP were calculated to be 92.593, 192.308, and 121.951 mg/g, respectively. RP showed a higher adsorption capacity of Cu(II) ions than PFP and DFP for all parameters. The results indicate that these biosorbents might be used to effectively adsorb Cu(II) ions from wastewater treatment plants.     

含氮超交联聚合物对磺胺二甲基嘧啶的吸附

通过一步法制备了一种含氮超交联吸附剂,探究了对水中磺胺二甲基嘧啶的去除能力,通过扫描电镜和红外光谱对超交联聚合物的表面结构和化学性质进行表征。结果表明,该吸附剂的最大吸附容量能够高达336.45 mg/g;吸附动力学过程符合准二级模型。     

基于吸附管采样/冷阱聚焦方法的环境大气VOCs富集系统研究

研制出一种基于吸附管采样/冷阱聚焦方法的环境大气挥发性有机物(Volatile organic compounds, VOCs)富集 系统。环境大气中的VOCs先被吸附管采样,之后转移聚焦至冷阱中,冷阱热解析后VOCs随高纯载气进入GC-FID系 统中。使用标准气体(苯、甲苯、乙苯)测定系统性能,实验结果表明:本系统设计的冷阱对于VOCs(苯系物)聚 焦效率达到90%以上,标准样品相对标准偏差均小于3%,线性相关系数均大于0.99。该系统运行稳定,满足对环境 大气的VOCs富集的需求。     

Adsorptive removal of trinitrophenol using nano α-Fe2O3/reduced graphene oxide

Abstract

2,4,6-Trinitrophenol (TNP), an explosive utilized for artillery munitions, ends up polluting water and soil. This study targets the treatment of TNP contaminated water via adsorption technique. A comparative adsorption study using pristine rGO (reduced graphene oxide), α-Fe₂O₃/rGO, bare α-Fe₂O₃ and physical mixture of α-Fe₂O₃ & rGO has been carried to select the most suitable adsorbent. To understand the mechanism of adsorption of TNP on α-Fe₂O₃/rGO adsorption isotherms were applied on adsorption data. The adsorption kinetics followed pseudo second order kinetic model. The mechanism of adsorption changed significantly with change in pH. The maximum adsorption capacity was found to be 769.23?mg?·?g^?1. Regeneration studies indicated that the adsorbent can be used up to 3 times without significant decrease in adsorption efficiency. Magnetic nature of adsorbent allowed its easy segregation from the contaminant solution upon application of external magnetic field. To assess the adsorption efficacy of α-Fe₂O₃/rGO in real water under ambient condition, TNP was spiked in ground water samples collected from adjoining district that had high TDS (Total dissolved solids). The Langmuir adsorption capacity of 164.24?mg?·?g^?1 was attained with substantial decrease in TDS. Thus α-Fe₂O₃/rGO proves to be an efficient adsorbent for nitrophenols and can be used commercially for waste water treatment.     

吸附法深度脱除燃料油中硫化物的研究进展

综述了吸附法深度脱除燃料油中硫化物的吸附机理及技术进展,主要包括物理吸附脱硫、反应吸附脱硫和选择性吸附脱硫的研究进展。物理吸附脱硫技术对硫化物的选择性较差且很难实现深度脱硫,而反应吸附脱硫在高温下才能有较好的吸附性能,吸附剂的再生温度较高。选择性吸附脱硫技术最具发展前景,操作条件温和,投资和操作费用低,能深度脱硫,是近期最有希望实现零硫目标的脱硫技术,但吸附剂对含硫化合物的选择性和硫含量还有待进一步提高。     

吸附树脂对紫草细胞培养生产紫草色素的原位提取

紫草（Ｌｉｔｈｏｓｐｅｒｍｕｍｅｒｙｔｈｒｏｒｈｉｚｏｎ）细胞在Ｍ－９培养基中培养时产生红色萘醌类化合物。实验表明，若在培养液中加入ＨＤ－１树脂，使色素和细胞产量下降，而Ｒ－Ａ树脂的加入却促进色素的合成和分泌，培养４ｄ的悬浮细胞中加入３０ｇ／ＬＲ－Ａ树脂，可使色素产量提高２倍。此外，还比较了原位提取和非原位提取体系细胞对碳源蔗糖的利用。     

包醛酶淀粉吸附性能的研究

本文介绍了肠溶制剂包醛酶淀粉在尿素溶液中的吸附性能，以及溶液的浓度，ｐＨ值，吸附剂用量对吸附性能的影响。结果表明，包醛酶淀粉的吸附速度大于包醛氧淀粉，吸附容量大约是包醛氧淀粉的４倍，当溶液ｐＨ〈４时，随着ｐＨ值减小，对溶液中尿素的吸附力迅速降低。     

微波辐射制备复合吸附剂对磷酸根的吸附性

用微波辐射制备无机复合吸附剂。将该吸附剂进行含磷废水的吸附试验，研究了静态吸附的动力学、热力学和再生条件。结果表明：该吸附剂对磷酸根的吸附符合一级反应动力学；平衡浓度与吸附容量符合Freundlich吸附等温线。失活的吸附剂在低的碱性溶液中很容易再生，解吸率可达98％，活化率为99％。