A project dissertation submitted to the Chemical Engineering Program Universiti Teknologi PETRONAS in partial fulfillment of the requirement for the. Due to the toxic nature of most dyes to humans, plants and micro-organisms, colored wastewater cannot be discharged without adequate treatment. I would like to express my deepest gratitude to the Chemical Engineering Department of Universiti Teknologi PETRONAS for the opportunity to undertake this remarkable final year project.
My knowledge was tested after completing four years of intensive chemical engineering course. I would like to express my gratitude to everyone who gave us the possibility to complete this report. I would especially like to send my sincere appreciation to my supervisor for her wholehearted guidance, encouragement, cooperation and constructive criticism throughout the duration of the project.
I would like to thank the project committee of the final year for organizing various seminars as support and knowledge to help the group with the project. I would also like to thank all the technicians and graduate students who contributed to the completion of the project.
INTRODUCTION
Project Background
Problem Statement
Taking into account the advantages and disadvantages of dye removal methods and the persistence in the nature and non-biodegradable properties of dye, adsorption has been used. Of all adsorption processes, activated carbon has been shown to be one of the most efficient adsorbents for the removal of dyes from wastewater. The use of alternative, low-cost materials with high adsorption activity to solve environmental problems has received significant attention in recent years.
Adsorbents from agricultural by-products are particularly advantageous because of their low cost and high availability as starting materials. In this work, I aim to use sawdust, taken from a furniture workshop, as an alternative low-cost sorbent in the removal of malachite green from aqueous solutions. Malachite green has properties that make it difficult to remove from aqueous solutions and also toxic to large microorganisms.
Although the use of this dye has been banned in some countries and is not approved by the US Food and Drug Administration, it is still being used in many parts of the world due to its low cost, ready availability, and efficacy. and the lack of a proper system. alternative. Therefore, the treatment of effluent containing such color is of interest because of its aesthetic impacts on receiving waters.
Objectives and Scope of Study
- Objectives
- Scopes of work
LITERATURE REVIEW
Freundlich adsorption isotherm
The driving force for adsorption on the surface is proportional to the concentration of the species in solution. The driving force is the concentration of the solution and the area is the amount of bare surface. If the adsorption takes place in a multilayer equilibrium on a homogeneous surface, the total multilayer adsorption capacity is
Malachite green does not contain the mineral malachite; the name comes from the similarity of color. The graph in Figure 4.7 shows that the amount of dye decreased as the amount of sorbent increased. Ce: the equilibrium concentration (mg/l), qe: the amount of adsorbed dye (mg/g), KF: Freundlich adsorption constant, and 1/n: a measure of the adsorption intensity.
Kn: equilibrium adsorption constant of the nth layer (L/mg) and Ce: equilibrium concentration of the solution (mg/L). The experiment started with the equilibrium study, which showed that the adsorption process of malachite green reaches equilibrium after 2.5 hours. However, if you compare the result of this study with that of others, plywood sawdust is not a good material used for removing malachite green.
Enhanced removal of malachite green from aqueous solution by rice straw modified with citric acid, Journal of Hazardous Materials, B137, p. Removal of malachite green from aqueous solution using defatted coffee beans, Journal of Hazardous Materials, 176, p. Batch removal of malachite green from aqueous solution by adsorption onto oil palm trunk fibers: Equilibrium isotherms and kinetic studies, Journal of Hazardous Materials, 154, p.
Removal of malachite green from dye wastewater using neem sawdust by adsorption, Journal of Hazardous Materials, 167, pp. Malachite green adsorption by rattan sawdust: Isothermal, kinetic and mechanism modeling, Journal of Hazardous Materials, 159, pp.574–57. Adsorption studies of hazardous malachite green on treated ginger waste, Journal of Environmental Management, 91, pp.
Langmuir adsorption isotherm
Multilayer adsorption isotherm
METHODOLOGY
Materials
- Dye solution – Malachite Green Oxalate
- Biosorbents
From the graph in figure 4.5 it is shown that the smaller the size of the sorbent, the more dye is adsorbed.
Preparation
- Adsorbate
- Adsorbent
- Characterization of the sorbent
Experiments
- Calibration curve
- Experiment 1: Equilibrium studies
- Experiment 2: Effect of solution pH
- Experiment 3: Effect of solution concentration
- Experiment 4: effect of sorbent size
- Experiment 5: Effect of temperature
- Experiment 6: Effect of different form of sorbent on biosorption
Once the calibration curve is prepared, the corresponding concentration of the solution as well as the amount of absorbed dye is known. The group equilibrium study is carried out by adding a fixed amount of 45-63 µm sorbent (0.1 g) to 250 mlrlenmeyer flasks containing 100 ml of 30 ppm dye solution at pH 5. The effect of sorbent size is studied by stirring 0 ,1 g and 100 ml saw. dye solution using a water bath shaker at 130 rpm and 40oC until equilibrium is reached.
The pH that gives the best absorption performance will be used for the next experiment. This experiment was conducted to find the optimal sorbent dose for 100 ml of 30 ppm dye solution. 100 ml of dye solutions with a concentration ranging from 5-30 ppm are contained in 250 ml conical flasks with 0.1 g of 45-63 µm sorbent in each flask.
Carry out the experiment under different temperature conditions in the range of 30oC – 80oC using water bath shaker at 130 rpm.
RESULT AND DISCUSSION
- Calibration Curve
- Characteristic of adsorbent
- Scanning Electronic Microscopy (SEM) Analysis
- FTIR (Fourier Transform Infrared Spectroscopy) Analysis
- Equilibrium study
- Effect of sorbent size
- Effect of initial pH
- Effect of adsorbent dosage
- Effect of operating temperature
- Effect of solution concentration
- Equilibrium isotherm
- Performance of sawdust – comparison with other sorbents
The 45-63 µm size is the most effective in this study, removing 86.5% of the dye in solution. The adsorption of this positively charged dye is influenced by the charge of the sorbent surface. The result shows that the availability of negatively charged groups is necessary for the adsorption of basic green.
The graph shows that the adsorption process is not favorable at pH less than 5 and pH in the wide range above 5 has no significant effect on adsorption. This is due to the presence of H3O+ in a highly acidic solution, which has a pH less than 5. Conversely, as the pH increases more negatively, the charged surface is available, thus facilitating greater removal of dye cations.
Therefore, to study the effect of temperature on adsorption of malachite green, batch sorption experiments were carried out at desired temperature and 80oC using 1g/L 45-63µm sorbent in 30ppm dye solutions. In order to study the effect of initial concentration of dye in the solution on the rate of adsorption on sawdust, the experiments were carried out at different initial dye concentrations which are 10, 20 and 30 ppm. At the beginning, the adsorption process occurred rapidly, indicating a high affinity between malachite molecules and sawdust surface.
This is because there is an optimal condition for each concentration of solution where the adsorption capacity of the sorbent is maximized. In multilayer adsorption, the amount of dye adsorbed in a subsequent layer must be less than in the previous layer. This indicates that the adsorption of MG on OPTF takes place as a multilayer adsorption on a surface that is homogeneous in adsorption affinity.
The most important parameter to compare is the Langmuir qm value as it is a measure of the adsorption capacity of the adsorbent. The adsorption capacity of plywood sawdust (this project) is not high compared to other sorbents. Furthermore, comparing qm value of normal and acid treated rice straw, the adsorption capacity of rice straw increases after acid treatment.
CONCLUSION
Dye removal from aqueous solution using adsorption on treated sugarcane bagasse, American Journal of Applied Sciences 2, 11, pp. Remediation of dyes in textile effluent: a critical review on current treatment technology with a proposed alternative, Bioresource Technology, 77, 3, p .Utilization of various agricultural wastes for activated carbon production and application for removal of dyes and metal ions from aqueous solutions, Bioresource Technology 87, 1, pp.
Evaluation of untreated coffee husk as a potential biosorbent for the treatment of dye-contaminated water, Journal of Hazardous Materials, 155, pp. Eye contact: Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting lower and upper eyelids. Containers of this material can be dangerous when empty, as they retain product residues (dust, solids); observe all warnings and precautions listed for the product.
Please refer to the ACGIH document, Industrial Ventilation, A Manual of Recommended Practices, latest edition, for details. For conditions of use where exposure to dust or mist is evident and engineering controls are not possible, a particulate mask (NIOSH type N95 or better filters) may be worn. Skin Protection: Wear impervious protective clothing, including boots, gloves, lab coat, apron, or coveralls, as appropriate, to prevent skin contact.
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