Abstract

Highly effective novel adsorbent [CoFe₂O₄-humic acid(HA)] was synthesized by co-precipitation technique at pH 6 (H6) and pH 8 (H8). XRD, S_BET and Zeta-potential measurements were used to study the physicochemical properties of the prepared nanoparticles. XRD results showed that the chemical treatment of CoFe₂O₄ by HA causes the appearance of carbon as new active sites for adsorption process. Batch adsorption tests were achieved to eliminate anionic remazole-red (RR-133) and cationic methylene blue (MB) dyes. The obtained data showed that H6 and H8 solids calcined at 300 and 500 °C have higher adsorption rate for removing of dye than unmodified cobalt iron mixed oxide. The removal reached 100% after a period of dye contact time 2 min and 30 min for RR and MB, respectively. The uptake of RR and MB was much affected by the pH of dye solution. The pseudo-second-order kinetic model was the most fitted well and the adsorption process followed the Langmuir isotherm model. The adsorption of dye on adsorbent was chemisorption process. The as-prepared adsorbents can be regenerated and reused four times for both dyes. The efficiency of the prepared nano-samples and durability as adsorbent were accomplished.

Graphic abstract

中文翻译：

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共沉淀过程中用腐殖酸处理的纳米钴铁氧体改善了从水溶液中去除染料的能力

摘要

通过共沉淀技术在pH 6（H6）和pH 8（H8）下合成了高效新型吸附剂[CoFe ₂ O _4-腐殖酸（HA）]。XRD，S _BET和Zeta电位测量用于研究制备的纳米颗粒的理化性质。XRD结果表明CoFe ₂ O ₄的化学处理由HA引起的碳的出现是吸附过程中新的活性位。通过分批吸附测试，消除了阴离子雷玛唑红（RR-133）和阳离子亚甲基蓝（MB）染料。获得的数据表明，在300和500°C下煅烧的H6和H8固体比未改性的钴铁混合氧化物具有更高的去除染料的吸附率。分别在RR和MB染料接触2分钟和30分钟后，去除率达到100％。染料溶液的pH值极大地影响了RR和MB的吸收。拟二级动力学模型拟合得最好，吸附过程遵循Langmuir等温模型。染料在吸附剂上的吸附是化学吸附过程。所制备的吸附剂可以再生，并且对于两种染料都可以重复使用四次。

图形摘要