The green chemistry method was used to extract humic acid from sediments obtained from Eniong River, Nigeria). The percentage yield of 0.2, 0.41 and 0.63 were obtained for 0.1, 0.5 and 1.0M NaOH respectively. The prepared humic acid (HA) was characterized using Ultraviolet-visible spectroscopy, Fourier transformed infrared spectroscopy (FTIR) and as well an investigating its surface properties. The spectrum confirmed the presence of surface functional group including -OH, -CO, -COOH. The UV spectrum was featureless typical of humic acids. The surface properties investigation showed that the extracted humic acid (EHA) was a mesoporous adsorbent with pore size between 2-50nm.
Table of Contents
1 INTRODUCTION
Background of Study
2 EXPERIMENTAL
2.1 Description of Study Area
2.2 Collection of Samples
2.3 Determination of Physical Properties and Nutrient Availability in River Sediment
2.3.1 Particle Size Analysis by Hydrometer Method
2.3.2 Determination of pH
2.3.3 Determination of Electrical Conductivity (EC)
2.3.4 Determination of Organic Carbon/Organic Matter by Walkley-Black Wet Oxidation Method
2.3.5 Determination of Exchange Acidity by 1M KC1 Method
2.3.6 Determination of Exchangeable Bases (Ca, Mg, Na, K)
2.3.7 Determination of Available Phosphorus Using Bray P1 Method
2.4 Preparation of Sample for Adsorption Process
2.4.1 Extraction of Humic Acid from a River Sediment
2.4.2 Purification of Aldrich Humic Acid (Reference HA)
2.4.3 Determination of HA Yield
2.4.4 Preparation of Aqueous MB Solution
2.5 Analytical Procedures
2.5.1 Characterization of HA using UV-Visible Spectroscopy
2.5.2 Characterization of HA Using FTIR
2.5.3 Determination of Surface Properties by Brunauer-Emmett-Teller (BET)
3 RESULTS AND DISCUSSION
3.1 Results
3.1.1 Physicochemical Parameters and Nutrient Availability in River Sediment
3.2 Yield of Extracted Humic Acid
4.3 Surface Area and Porosity Property of Extracted Humic Acid
3.4 Characterization of Extracted Humic Acid
3.4.1 UV-visible Characterization of Humic Acid
4.4.2 Degree of Humification and Condensation for Aldrich and extracted HAs
4.4.3 FTIR Spectra of Humic Acids
4 CONCLUSION
Research Objectives and Themes
The primary research objective is to investigate the feasibility of using humic acid extracted from the sediments of the Eniong River, Nigeria, as a cost-effective adsorbent for the removal of dyes from aqueous solutions. The study examines the chemical characteristics, surface properties, and potential adsorption capabilities of the extracted material.
- Extraction and yield optimization of humic acid using various NaOH concentrations.
- Physicochemical characterization of river sediments and extracted humic acid.
- Analysis of surface functional groups using FTIR spectroscopy.
- Evaluation of surface area and porosity using the Brunauer-Emmett-Teller (BET) method.
- Comparative analysis of extracted humic acid with commercial reference samples.
Excerpt from the Book
2.4.1 Extraction of Humic Acid from a River Sediment
A modified method of Barot and Belga (2009) was used in the extraction of humic acid from the sample. Fifty grams (50 g) of the sample were measured into conical flasks and pre-treated with 50ml of 0.1 M HCl to remove calcium (Ca) and other polyvalent cations, carbonates, also to increase the yield of humic acid and efficiency of extraction with alkaline reagent. The slurry thus obtained was extracted with 200ml of 0.5 M NaOH respectively. The mixture was stirred on an orbital shaker at 120 rpm for 24 hr and then allowed to stand overnight. Subsequently, the solutions were filtered through Whatman No. 1001240 filter paper and the filtrate was acidified to pH 1 by addition of concentrated 6 M HC1 at room temperature with constant stirring so as to minimize the heat of neutralization. The suspensions in different flasks were left standing for one night to allow the precipitated HAs to settle. A solid blackbrown coloured precipitate was obtained representing crude HA fraction, while a yellow coloured supernatant was the crude filvic fractions (FA). The contents of the flasks were further centrifuged at 4000 rpm for 15 min to separate HA from FA. The solid HA was washed several times with double distilled water until the last washing water gave a negative chloride test with silver nitrate. The HA was then dried in an oven at 110 oC. The extraction was repeated with 1 M NaOH.
Summary of Chapters
1 INTRODUCTION: This chapter provides the historical context of humic substance research and discusses the role of humic acid as a component of natural organic matter in soil and water environments.
2 EXPERIMENTAL: This section details the methodology for collecting river sediment and the specific laboratory procedures used for determining physicochemical properties and extracting humic acid.
3 RESULTS AND DISCUSSION: This chapter presents the analytical findings regarding the sediment composition, extraction yields, and the spectroscopic and textural characterization of the humic acid samples.
4 CONCLUSION: This chapter summarizes the study's findings, confirming the mesoporous nature of the extracted humic acid and noting the influence of sediment characteristics on extraction yield.
Keywords
Humic acid, Eniong River, Sediment, Extraction, Adsorption, Green chemistry, FTIR, UV-visible spectroscopy, Mesoporous, BET, Surface area, Porosity, Methylene blue, Humification, Physicochemical properties
Frequently Asked Questions
What is the core subject of this research paper?
The paper focuses on the extraction and characterization of humic acid from sediment samples collected from the Eniong River in Nigeria to explore its potential as a low-cost adsorbent.
What are the central thematic areas?
The central themes include soil chemistry, the extraction of organic substances from river sediments, and the structural characterization of humic acids using spectroscopic and textural analysis techniques.
What is the primary objective of this study?
The primary objective is to determine if humic acid extracted from Eniong River sediment can serve as an effective, sustainable alternative to traditional adsorbents for wastewater treatment.
What scientific methods were employed?
The study utilized green chemistry extraction techniques, UV-visible spectroscopy, FTIR spectroscopy for identifying functional groups, and the BET method for assessing surface area and porosity.
What is covered in the main body of the paper?
The main body details the sampling of river sediment, the step-by-step extraction process, the measurement of physical and chemical parameters, and a thorough analysis of the resulting humic acid structure.
Which keywords characterize this research?
Key terms include humic acid, Eniong River, extraction, mesoporous, adsorption, FTIR, and sediment analysis.
What did the surface area and porosity analysis reveal about the extracted humic acid?
The BET analysis indicated that the extracted humic acid possesses a mesoporous structure, which makes it suitable for adsorbing dye molecules like methylene blue.
How did the concentration of the extractant influence the yield of humic acid?
The study found that the yield of humic acid increased with higher concentrations of the extractant (NaOH) in the order of 0.1 M < 0.5 M < 1.0 M.
- Quote paper
- Ofonime Udo (Author), 2015, Extraction of humic acid from sediment obtained from Eniong River, Nigeria, Munich, GRIN Verlag, https://www.grin.com/document/296182
