共查询到17条相似文献,搜索用时 171 毫秒
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随着抗生素药物(如四环素)的大量使用,近几年抗生素的环境行为和毒性已经成为人们的研究焦点和热点.我国的地表水、地下水、市政污水、养殖废水等不同水体中都检测到了四环素等抗生素药物,引发的水生态问题受到了众多学者的广泛关注.生物炭因具有制备来源广泛且易得廉价、比表面积大、孔隙发达、官能团种类较多等优点被学者们重点关注,已有众多文献报道发现不同种生物炭对四环素的吸附具有优越的性能.本文综述了近年来不同生物质制备的生物炭对四环素的吸附影响以及不同水化条件对四环素对生物炭吸附特征的影响,并阐述了生物炭吸附四环素过程中所涉及的机理.对进一步探究生物炭对四环素吸附的影响具有一定的指导意义. 相似文献
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四环素类抗生素是一类广谱抗生素,广泛应用于治疗由革兰阳性和阴性细菌、支原体、衣原体和立克次氏体感染所引起的疾病.四环素类抗生素药物由ABCD四个六元并环骨架结构所构成.目前,人们主要通过发酵途径获得四环素类天然抗生素,再通过化学半合成的方式对其进行结构改造,其中A环取代方式固定,人们主要对D环作结构改造以获得临床药效更加优异的非天然新型四环素类抗生素药物.自1962年四环素Sancycline全合成工作以来,合成工作者们完成了多个四环素类抗生素药物的全合成,如近年通过发展新颖合成策略完成了四环素类抗生素药物Doxycycline的全合成;其后,人们通过全合成高效地完成了其他四环素类抗生素药物的合成和结构改造,加速了新型四环素类抗生素药物的研发与上市.本综述归纳总结了四环素类药物的发现和发展史,并介绍了其生物合成机制和针对病原菌的药物作用模式,详细介绍并比较了各种四环素类药物的半合成和全合成方式,将为研究者了解四环素抗生素及其结构类似药物的发现、发展和合成空间等起到有益作用. 相似文献
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随着农药的广泛使用,其已普遍存在于环境中,对人们的身体健康产生巨大影响。因此,环境中农药残留的去除和分析检测对保护人体安全健康至关重要。同时,农药在环境中残留浓度低,需要一种对目标物有较强选择性和富集作用,并对环境影响小的前处理吸附剂。植物源生物炭是由植物源生物质作为碳源衍生得到的材料,其比表面积大、孔容量高、表面官能团可调节,且环境相容性好,其原料植物源生物质的价格低廉、来源广泛并可再生,是一种廉价高效的吸附剂。该文主要综述了近10年来植物源生物炭用于环境中农药残留去除和分析检测前处理的应用进展。其中在农药残留去除方面的应用主要包括降低农药在土壤中的移动性,修复手性农药造成的污染,负载降解农药的细菌及作为化肥的缓释载体。在农药残留分析检测前处理方面,植物源生物炭可用作分散固相萃取、固相微萃取和磁性固相萃取的吸附剂来选择性吸附水果和蔬菜中的有机磷类和三唑类农药,以及水环境中的有机氯类农药。另外,还介绍了植物源生物炭的吸附机理,详细阐述了基于计算模拟如密度泛函理论、分子动力学模拟和巨正则蒙特卡洛模拟的吸附机理研究并讨论了其优势。最后,总结了植物源生物炭在农药去除和农药残留分析检测前处理方面应用的优势,指出了其在农药残留领域应用待解决的问题。 相似文献
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草酸改性空气凤梨生物炭吸附甲醛的机理研究 总被引:1,自引:0,他引:1
探究草酸改性园林废弃物类生物炭对溶液中甲醛的吸附效率和固定的机理,为园林废弃物类生物炭在甲醛污染控制方面的应用提供科学依据.利用马弗炉在低氧条件下将空气凤梨原材料和草酸改性后的原材料制备成生物炭.然后利用实验室模拟法,研究不同反应时间、甲醛浓度、pH对生物炭吸附效果的影响,并分析草酸改性如何提高园林废弃物类生物炭对甲醛... 相似文献
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六价铬(Cr(Ⅵ))是自然环境中毒性很强的重金属污染物之一,对生态系统构成严重威胁。生物炭是生物质在缺氧条件下热解产生的一种富碳固体物质,因具有比表面积大、孔结构发达和官能团丰富等优点,可作为修复Cr(Ⅵ)污染的高效吸附材料。目前,研究人员主要通过物理改性、化学改性、负载金属改性及生物改性等多种策略进一步增强生物炭对Cr(Ⅵ)的吸附能力。本文综述了近年来生物炭改性的研究进展,系统梳理了不同生物炭改性策略,比较了不同改性策略制备的生物炭对Cr(Ⅵ)污染的修复效率,分析了其作用机制,并对生物炭的改性修饰及其在实际应用中的未来发展方向进行了讨论。 相似文献
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挥发性有机物(VOCs)是大气中重要的污染源之一,对环境和人类健康产生严重的危害。吸附法是工业中最常用的去除VOCs的方法,吸附剂是吸附技术的关键,生物质炭是一种由生物质基材料在高温下热解活化等工艺制得的炭材料,具有较高的比表面积、丰富的孔隙结构和化学活性表面,在环境污染控制领域具有广泛应用。基于最近的研究,本文系统地综述了常用于去除VOCs的生物质炭的制备和改性方法,以及生物质炭在吸附VOCs的应用研究。本文首要目标是评估生物质炭去除VOCs的能力,特别是经过各种改性和活化工艺后,评价生物质炭作为吸附剂去除VOCs的适用性;确定改性和活化后对VOCs吸附能力的影响;揭示生物质炭对VOCs可能存在的吸附机理。最后,文章也对生物质炭的再生提出了建议和展望。 相似文献
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Biochar, produced and activated from thermochemical methods, was applied as catalyst for catalytic biorefinery and environmental pollutant removal. In this review, recent advanced studies of biochar catalyst were discussed. 相似文献
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Lignocellulosic biomass is an abundant and environment-friendly source for renewable energy production. The value and application of biochar, which is obtained from the thermochemical conversion of biomass, is increasing rapidly because of its high carbon content and porosity. The property of biochar, such as surface area, porosity, and number of functional groups, can be improved by controlling the conditions of biomass conversion, biochar activation, and functionalization methods. The production and activation of biochar as well as its potential use for soil remediation, pollutant adsorption, and biorefinery have been reviewed extensively over recent decades. This paper provides a conceptual approach for biochar production and activation together with its application as a catalyst for biorefineries and the removal of environmental contaminants. 相似文献
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Removal of steroid hormones from aqueous environment is of prevailing concern because of their adverse impact on organisms. Using biochar derived from biomass as adsorbent to remove pollutants has become more popular due to its low cost, effectiveness, and sustainability. This study evaluated the feasibility of applying corn straw biochar (CSB) and dewatered sludge biochar (DSB) to reduce 17β-estradiol (E2) from aquatic solutions by adsorption. The experimental results showed that the adsorption kinetics and isotherm behavior of E2 on the two biochars were well described by the pseudo-second-order (R2 > 0.93) and Langmuir models (R2 > 0.97). CSB has higher E2 adsorption capacity than DSB, and the maximum adsorption capacity was 99.8 mg/g obtained from Langmuir model at 298 K, which can be attributed to the higher surface area, porosity, and hydrophobicity of this adsorbent. Higher pH levels (>10.2) decreased the adsorption capacities of biochar for E2, while the ionic strength did not significantly affect the adsorption process. The regeneration ability of CSB was slightly better than that of DSB. The possible adsorption mechanism for E2 on biochar is suggested as π–π interactions, H–bonding, and micropores filling. These results indicated that CSB has more potential and application value than DSB on reducing E2 from aqueous solutions when considering economy and removal performance. 相似文献
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《Journal of Saudi Chemical Society》2020,24(11):824-834
The purpose of this study was to develop an efficient method of biochar modification for effective removal of Se(VI) ions from water. Commercially available biochar produced from wheat straw was impregnated by Fe(NO3)3 (0.8, 4 and 10% w/v) and pyrolyzed at 200 °C. Optimum pH, adsorption kinetics, and Se(VI) adsorption isotherms were determined for the studied biochars. The modification significantly increased biochar’s ability for Se(VI) adsorption. The biochar modified with 10% Fe(NO3)3 has the highest adsorption effectiveness. The experimentally determined maximum adsorption capacity for the biochar modified with 10% Fe(NO3)3 was 14.3 mg g−1 for pH 5, which was the optimum pH value. X-Ray Photoelectron Spectroscopy (XPS) and Photoacoustic Fourier Transform Infrared Spectroscopy (FTIR-PAS) investigation confirmed the presence of iron oxides/hydroxides on the surface of the modified biochar. The modification also resulted in the formation of oxygen containing functional groups. The study proved that the proposed modification can be efficient in increasing the biochar effectiveness in removing Se(VI) from water. 相似文献
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《中国化学快报》2022,33(6):3097-3100
In this work, a modification method of H3PO4 plus H2O2 (PHP) was introduced to targetedly form abundant oxygenated functional groups (OFGs) on biochar, and methylene blue (MB) was employed as a model pollutant for adsorption to reflect the modification performance. Results indicated that parent biochars, especially derived from lower temperatures, substantially underwent oxidative modification by PHP, and OFGs were targetedly produced. Correspondingly, approximately 21.5-fold MB adsorption capacity was achieved by PHP-modified biochar comparing with its parent biochar. To evaluate the compatibility of PHP-modification, coefficient of variation (CV) based on MB adsorption capacity by the biochar from various precursors was calculated, in which the CV of PHP-modified biochars was 0.0038 comparing to 0.64 of the corresponding parent biochars. These results suggested that the PHP method displayed the excellent feedstock compatibility on biochar modification. The maximum MB adsorption capacity was 454.1 mg/g when the H3PO4 and H2O2 fraction in PHP were 65.2% and 7.0%; the modification was further intensified by promoting temperature and duration. Besides, average 94.5% H3PO4 was recovered after 10-batch modification, implying 1.0 kg H3PO4 (85%) in PHP can maximally modify 2.37 kg biochar. Overall, this work offered a novel method to tailor biochar towards OFGs-rich surface for efficient adsorption. 相似文献
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选取玉米秸秆为原料, 经过缺氧炭化制备玉米秸秆生物炭, 并以聚乙烯亚胺(PEI)负载于生物炭表面, 制备PEI功能化秸秆生物炭, 研究了其对水中Cr 6+的吸附性能和机理. 结果表明, 在吸附剂添加量相等条件下, PEI碱性生物炭(PBC)对Cr 6+的吸附效率明显高于PEI酸性生物炭(HBC)和原始生物炭(CBC). PBC对水中Cr 6+的最大吸附量为386.3 mg/g, 吸附平衡时间为300 min; 当pH=2.0左右时, 对Cr 6+的吸附效率最大达到95.94%. 因此, PBC可作为一种高效去除水中Cr 6+的吸附剂. 相似文献
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《Arabian Journal of Chemistry》2022,15(5):103750
Co-pyrolysis of straw and Ca(OH)2 is a feasible modification method to improve the adsorption capacity of biochar for Cd. However, few studies have quantitatively analyzed the contribution of different adsorption mechanisms of alkali-modified biochar. In this study, the alkali-modified (Ca) biochar were prepared by co-pyrolyzing lime (Ca(OH)2) and soybean straw (SBB) or rape straw (RSB) at 450 °C. The adsorption mechanism was investigated by a series of experiments and was provided by quantitative analysis. The maximum adsorption capacities of Cd2+ by Ca-SBB and Ca-RSB were calculated to be 78.49 mg g?1 and 49.96 mg g?1, which were 1.56 and 1.48 times higher than SBB (50.40 mg g?1) and RSB (33.79 mg g?1), respectively. Compared with the original biochar (SBB, RSB), alkali-modified biochar (Ca-SBB and Ca-RSB) were found to have faster adsorption kinetics and lower desorption efficiencies. The mechanism study indicated that Ca(OH)2 modification effectively enhanced the contribution of ion exchange and decreased the contribution of functional groups complexation. After Ca(OH)2 modification, precipitation and ion exchange mechanisms dominated Cd2 + absorption on Ca-SBB, accounting for 49.85% and 34.94% of the total adsorption, respectively. Similarily ion exchange and precipitation were the main adsorption mechanism on Ca-RSB, accounting however for 61.91% and 18.47% of total adsorption, respectively. These results suggested that alkali-modified biochar has great potential to adsorp cadmium in wastewater. 相似文献