Fly ash (FA) is a major industrial waste generated from power stations that add extra cost for proper disposal. Recent research efforts have consequently focused on developing ways to make use of FA in environmentally sound applications. This study, therefore, investigates the potential ability of raw fly ash (RFA) and polyelectrolyte-coated fly ash (PEFA) to remove cadmium (Cd) from polluted water. Using layer-by-layer approach, functionalized fly ash was coated with 20 layers from 0.03% (v/v) of cationic poly(diallyldimethylammonium chloride) (PDADMAC) and anionic polystyrene sulfonate (PSS) solutions. Both surface morphology and chemical composition of the adsorbent (PEFA) were characterized using Field-Emission Scanning Electron Microscope (FE-SEM), X-Ray Diffraction (XRD), Fourier-Transform Infrared (FTIR), and X-Ray Fluorescence (XRF) techniques. The effects of pH, adsorbent dosage, contact time, initial contaminant concentration, and mixing rate of the adsorption of Cd were also studied in batch mode experiments. Results of the study revealed that a 4.0 g/L dosage of PEFA removed around 99% of 2.0 mg/L of Cd in 15 min at 150 rpm compared to only 27% Cd removal achieved by RFA under the same conditions. Results also showed that adsorption by PEFA followed both Langmuir and Freundlich models with correlation coefficients of 98% and 99%, respectively.

中文翻译：

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使用聚电解质涂覆的工业废粉煤灰从污染水中去除镉。

粉煤灰（FA）是发电厂产生的主要工业废物，为适当处置增加了额外成本。因此，最近的研究工作集中在开发在无害环境的应用中利用FA的方法。因此，本研究调查了原粉煤灰（RFA）和聚电解质包覆粉煤灰（PEFA）从污水中去除镉（Cd）的潜在能力。使用逐层方法，将功能化的粉煤灰涂覆20层，占0.03％（v / v）的阳离子聚二烯丙基二甲基氯化铵（PDADMAC）和阴离子聚苯乙烯磺酸盐（PSS）溶液。使用场发射扫描电子显微镜（FE-SEM），X射线衍射（XRD），傅立叶变换红外（FTIR）表征了吸附剂（PEFA）的表面形态和化学成分。和X射线荧光（XRF）技术。还通过分批模式实验研究了pH，吸附剂用量，接触时间，初始污染物浓度和Cd吸附混合速率的影响。研究结果显示，在150 rpm下15分钟内，4.0 g / L剂量的PEFA去除了约99％的2.0 mg / L镉，而RFA在相同条件下仅去除了27％的镉。结果还表明，PEFA的吸附均遵循Langmuir和Freundlich模型，相关系数分别为98％和99％。在15分钟内以150 rpm的速度去除0 mg / L的Cd，相比之下，RFA在相同条件下的去除率仅为27％。结果还表明，PEFA的吸附均遵循Langmuir和Freundlich模型，相关系数分别为98％和99％。在15分钟内以150 rpm的速度去除0 mg / L的Cd，相比之下，RFA在相同条件下的去除率仅为27％。结果还表明，PEFA的吸附均遵循Langmuir和Freundlich模型，相关系数分别为98％和99％。