Abstract:
This study evaluates the adsorptive capacity of elephant grass (EG) in the removal of Methylene blue (MB) dye from wastewater sourced from two major local dyeing industries in Ogun State, Nigeria. Batch adsorption method was used to determine the optimum conditions, characterization of the adsorbent, equilibrium Isotherm models, kinetics and thermodynamics studies were conducted to evaluate the nature of the adsorption process. The optimum adsorption conditions obtained for the standard solution of MB dye were; pH 7, Temp 40 °C, contact time 180 min and adsorbent dosage 2.0 g. The presence of oxygen containing functional groups and shift or disappearance of bands in the FTIR suggested the suitability of EG for the process. The SEM of EG revealed presence and disappearance of pores before and after the adsorption process. The mechanism of this adsorption is complex, the adsorption data is best fitted to Langmuir isotherm, the mean adsorption energy E (≤6.455 kJ/mol), and activation energy (10.84 kJ/mol) represents physical process but, the thermodynamic studies revealed spontaneity (ΔG° -15.93 to -14.26 kJ mol-1), randomness, and endothermic (ΔH° 40.1 kJ/mol) nature, representing chemisorption. Therefore, local dyers around the study sites can make use of the freely available EG for the remediation of their wastewater.
Elephant grass (EG) abundantly thrives on the study sites where dye wastewater is released by local dyers. This serves as the impetus for this research as no other plants thrive on the dye-polluted environment. A favorable adsorption was obtained with EG as adsorbent for the Methylene blue (MB) dye that is a major constituent of the wastewater from the two major local dyeing industries investigated. Therefore, this study provides scientific support for the local dyers around the study sites to make use of the freely available EG for the remediation of their wastewater.
摘要:
这项研究评估了象草(EG)在去除来自奥贡州两个主要本地染色行业的废水中亚甲基蓝(MB)染料的吸附能力,尼日利亚。采用批量吸附法确定了最佳工艺条件,吸附剂的表征,平衡等温线模型,进行了动力学和热力学研究,以评估吸附过程的性质。MB染料标准溶液的最佳吸附条件为;pH7,温度40°C,接触时间180分钟和吸附剂剂量2.0g。在FTIR中含氧官能团的存在和条带的移动或消失表明EG对该方法的适用性。EG的SEM显示了吸附过程前后孔的存在和消失。这种吸附的机理是复杂的,吸附数据最符合朗缪尔等温线,平均吸附能E(≤6.455kJ/mol),活化能(10.84kJ/mol)代表物理过程,但热力学研究揭示了自发性(ΔG°-15.93至-14.26kJmol-1),随机性,和吸热(ΔH°40.1kJ/mol)性质,代表化学吸附。因此,研究地点周围的本地染料工人可以利用免费提供的EG来修复其废水。
象草(EG)在研究地点大量生长,染料废水被当地的染料释放。这是本研究的动力,因为没有其他植物在染料污染的环境中茁壮成长。使用EG作为亚甲基蓝(MB)染料的吸附剂获得了良好的吸附,亚甲基蓝是所研究的两个主要本地染色行业废水的主要成分。因此,这项研究为研究地点周围的当地染工提供了科学支持,以利用免费提供的EG来修复其废水。