INVESTIGATING THE INFLUENCE OF ACTIVATION TEMPERATURE ON YIELD AND METHYLENE BLUE ABSORPTION OF ACTIVATED CARBON

INVESTIGATING THE INFLUENCE OF ACTIVATION TEMPERATURE ON YIELD AND METHYLENE BLUE ABSORPTION OF ACTIVATED CARBON

ABSTRACT

 Activated carbon is used in numerous environmental applications for gas contaminants uptake, filtration, removal of odour, purification etc. Themajor factors that determine the application of activated carbon for specific application are surface area, pore size and surface chemistry of the carbon.One of the research objectives of this project is to explore the possibility of using carbonaceous materials to produce activated carbon for different uses, such as adsorbents in liquid and gas phases, catalysts and support for catalysts. So far, we have used coal to produce activated carbons by investigating the influence of activation temperature on yield and methylene blue absorption of activated carbon

CHAPTER ONE

 1.0       INTRODUCTION:

Activated carbon is a well-known absorbent that has been used effectively for a removal of broad spectrum of pollutants from air, soil and liquid. Adsorption unto activated carbon has been found to be superior to other techniques because of its capability of absorbing a wide range of different types of adsorbents efficiently and simplicity of design.  It has been reported that activated carbon as absorbent have many applications due to its nature and properties. A large of number of materials has been used in the preparation of activated carbon, many carbonaceous materials of animal, vegetable or mineral origin can be converted into activated carbon if properly treated. By O.F Okeolaetal. (2010).

By definition Activated Carbon which is also called activated charcoal, or activated coal is a form of carbon having fine pores used chiefly for adsorbing gases or solutes, as in various filter systems for purification, deodourization, and decolourization(www.dictionary.com/browse/activated-carbon).

 Activated Carbosn is the generic term used to describe a family of carbonaceous adsorbents with a highly crystalline form and an extensively developed internal pore structure. Many types of activated carbon products are available, each exhibiting markedly different characteristics depending upon the raw material and activation techniques in their production.

The use of carbon in the form of charcoalhas been used since antiquity for many applications.

In Hindu documents dating from 450 BC charcoalfilters are mentioned for the treatment ofwater. Charred wood, bones and coconut charcoalswere used during the 18th and 19th centuryby the sugar industry for decolourising solutions (CECEN 2011). Activated carbon is a materialprepared in such a way that it exhibits a high degree of porosity and an extended surface area.

During waterfiltrationthrough activated carbon,contaminants adhere to the surface of these carbongranules or become trappeding the small pores of the activated carbon (AMIRAULTet al. 2003). This process is called adsorption. Activatedcarbon filters are efficient toremove certain organics (such as unwanted taste andodours, micropollutants),chlorine, fluorine or radon,from drinking wateror wastewater. However, it isnot effective for microbialcontaminants, metals,nitrates and other inorganic contaminants.

Activated carbons can be produced from a large variety of raw materials, basically by two methods:

Physical or chemical activation or a combination of both of them. The physical activation method involves carbonization of the raw material and the subsequent activation at high temperature in a carbon dioxide or steam atmosphere. The chemical activation method involves the carbonization of the raw material previously impregnated with a chemical agent.

1.1       Aim and Objectives

The aim of this research work is to produce activated carbon via physical activation method from coal which yields maximum pore size or surface area.

 Objectives

 The objectives of this research work are:

1. Use of coal as the primary source of carbonaceous raw material.
2. Determination of the pore size of the activatedcarbon.

1.2       Justification

Activated carbons works by adsorption – the process by which a gas bonds to the surface of a solid. In this case, the solid is the activated carbon, which adsorbs as much as 60% of its weight in airborne pollutants. Air passes through the filter where airborne gases, chemicals, and odours react chemically with the surface of the carbon, effectively sticking to it. They have a large capacity for removing organic molecules like solvents. They can also simultaneously adsorb many different kinds of chemicals,making these filters very efficient.

Activated carbons works in any temperature or humidity and isn’t toxic, so it’s safe for people to handle.  Thankfully, it’s also quite affordable. Activated carbon filters effectively work like a sponge. The more activated carbon in the filter, the more pollutants it can remove and the longer the filter lasts. Activated carbon filters are the most effective way to remove gases, chemicals, cigarette smoke, and other odours from the air.

1.3       Scope of the Work

There are numerous carbonaceous rich materials such as coal, peat, lignite, wood, coir, and coco-nut shells used for the production of activated carbon but in this research work, we are restricted to the use of coal because its generate maximum pore size due to high temperature application. The scope of work reported here cover the production, properties, and uses of activated carbon.

1.4       Limitations

            The limitation of this research/ project work includes the following:

1. Lack of standard testing equipment
2. Lack of standard laboratory within the school for the production and analysis which make the work somehow difficult as transport and hiring of equipment was involved.
3. We are limited to using coal which was cumbersome to source around.