表面活性剂改性亚麻秸秆对酸性偶氮染料的吸附性能研究

发布时间：2018-05-13 06:04

本文选题：染料废水 + 改性亚麻秸秆　；参考：《华北电力大学(北京)》2017年硕士论文

【摘要】：染料按照化学成分可被分为阳离子染料、阴离子染料和非离子染料,其被广泛运用于纺织、印刷、造纸、电镀、食品加工、塑料制品加工等行业。中国染料工业在近年得到迅速发展,据统计,2015年染颜料的产量合计达到115万吨,染颜料中间体合计达到32万吨,已成为世界领先的染料生产商和供应商。酸性染料是一种水溶性的阴离子染料,其分子结构中含有-SO3Na或-COONa酸性基团。酸性染料按照分子类型又可分为偶氮型、蒽醌型、三芳甲烷型、亚硝基型等,偶氮染料是其中种类较多且使用量较大的一类。酸性染料结构简单,水溶性好,色谱齐全且色彩鲜艳。染料废水由其生产产业和使用产业大量排放进入环境,目前由于许多印染企业的水处理技术的欠缺以及人们环保意识的薄弱,对于产生的各类染料废水只极少数经过有效处理后达标排放,这也使得染料废水成为水环境污染的一大重要因素。因染料废水具有色度高、毒性大、成分复杂以及极低的生化性等特点而对环境造成了严重的污染。有些染料分子,尤其是偶氮染料,对生物具有致畸、致癌、致突变作用,排入环境后不仅会对生物群体产生危害,甚至会引起人体病变或诱发癌症。所以寻找高效经济的染料废水处理方法是非常必要的。亚麻秸秆是产生于亚麻纤维加工业过程中的一种木质残留物。大多数的亚麻秸秆被丢弃或者被焚烧,这不仅造成了生物资源的浪费,同时也造成了严重的环境污染问题。作为一种来源广泛的农业废弃物,亚麻秸秆本身含有一定量的木质素和纤维素,具有成为优良染料吸附剂的潜质。本文以亚麻秸秆为研究对象,在将其用两种不同结构的表面活性剂改性后,作为吸附剂去除水溶液中的三种酸性偶氮染料(酸性橙7,酸性红18和酸性黑1),探讨三种染料在改性亚麻秸秆上的吸附性能。整个吸附过程还受到溶液的初始p H、吸附剂投加量、溶液的离子强度以及体系反应温度等方面的影响。研究结果表明:CTMAB改性亚麻秸秆对三种酸性偶氮染料具有良好的吸附去除效果。三种染料的去除率随溶液p H值的增加而下降,最大吸附量在pH为2时获得;随着吸附剂投加量的增加,三种染料去除率明显上升;而离子强度的增加却导致了三种染料去除率的下降;CG-12改性亚麻秸秆吸附三种酸性偶氮染料的研究中,溶液初始p H、吸附剂投加量以及离子强度的影响与CTMAB改性亚麻秸秆吸附相似。此外,在CG-12改性亚麻秸秆吸附三种染料的实验中,还通过全因子设计实验考察了因素间的交互作用对吸附的影响,结果表明其中影响比较显著的是反应温度和吸附剂投加量之间的作用;三种染料在两种改性亚麻秸秆吸附剂上的吸附都可以用Langmuir吸附等温线模型很好地描述,吸附动力学实验数据均符合二级动力学模型。热力学数据表明三种染料在改性亚麻秸秆上的吸附均为自发过程。
[Abstract]:Dyes can be divided into cationic dyes, anionic dyes and non-ionic dyes according to their chemical composition. They are widely used in textile, printing, papermaking, electroplating, food processing, plastic products processing and other industries. The dyestuff industry of China has been developing rapidly in recent years. According to statistics, the total output of dyestuff reached 1.15 million tons in 2015, and the sum of dyestuff intermediate reached 320000 tons in 2015. China has become the world's leading manufacturer and supplier of dyes. Acid dyes are water-soluble anionic dyes, and their molecular structures contain -SO _ 3Na or -COONa acid groups. Acid dyes can be divided into azo type, anthraquinone type, triaromatic methane type and nitroso type according to their molecular types. Azo dyes are one of the most widely used ones. Acid dyes have simple structure, good water solubility, complete chromatography and bright colors. Dye wastewater is discharged into the environment by its production and use industries. At present, because of the lack of water treatment technology in many printing and dyeing enterprises and the weakness of people's awareness of environmental protection, Only a few dyestuff wastewater can be discharged to the standard after effective treatment, which makes the dye wastewater become an important factor of water environment pollution. Because of its high chromaticity, high toxicity, complex composition and very low biochemistry, dyestuff wastewater has caused serious pollution to the environment. Some dye molecules, especially azo dyes, have teratogenic, carcinogenic and mutagenic effects on organisms. Therefore, it is very necessary to find efficient and economical treatment method of dye wastewater. Flax straw is a kind of wood residue produced in flax fiber processing industry. Most flax stalks were discarded or burned, which not only caused the waste of biological resources, but also caused serious environmental pollution. As a kind of agricultural waste, flax straw contains a certain amount of lignin and cellulose, which has the potential to become an excellent dye adsorbent. In this paper, flax straw was modified with two different surfactants. Three kinds of acid azo dyes (acid orange 7, acid red 18 and acid black 1) were removed from aqueous solution as adsorbent. The adsorption properties of the three dyes on modified flax straw were investigated. The adsorption process is also affected by the initial pH of the solution, the dosage of adsorbent, the ionic strength of the solution and the reaction temperature of the system. The results showed that the modified flax straw modified with 1: CTMAB had a good adsorption and removal effect on three kinds of acid azo dyes. The removal rate of the three dyes decreased with the increase of pH value of the solution, and the maximum adsorption capacity was obtained at pH 2, and the removal rate of the three dyes increased with the increase of the amount of adsorbent. However, the increase of ionic strength resulted in the decrease of the removal rate of three dyes, and the adsorption of three kinds of acid azo dyes by CG-12 modified flax straw. The effects of solution initial pH, adsorbent dosage and ionic strength were similar to those of CTMAB modified flax straw. In addition, in the experiment of adsorption of three dyes by CG-12 modified flax straw, the effect of the interaction of factors on the adsorption was investigated through the experiment of full-factor design. The results show that the effect of reaction temperature and the amount of adsorbent on the adsorption of three dyes on two modified flax straw adsorbents can be described by Langmuir adsorption isotherm model. The experimental data of adsorption kinetics all accord with the second order kinetic model. Thermodynamic data showed that the adsorption of the three dyes on modified flax straw was a spontaneous process.
【学位授予单位】：华北电力大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X703

【参考文献】