SYNTHESIS OF ACTIVATED CARBON. A RESEARCH PROJECT TOPICS ON CHEMICAL ENGINEERING
This project was carried out using coal sample from Onyeama coal mine Enugu, Enugu State. Activated coal was produced by carbonizing the coal and activating it using phosphoric acid at a temperature of 5500c. the degree of bleaching of raw palm oil was monitored using spectronic meter through absorbance measurement. The essence was to identify suitability of the coal as a bleaching agent on palm oil. Comparison of the result obtained was made with the commercial fuller’s earth.
From the result obtained that 0.45mm, 0.18mm and <0.075mm particle size of the activated coal was used at size and at variable temperature of 1200c, 1600c and 2000c were carried out, the average percented colour absorption for the activated coal from Enugu was found to be 80, 81 and 89 respectively. This, the optimal particle size, temperature and weight was obtained to be 0.18mm 2000c and log/100ml of palm oil respectively.
Further it was identified that the smaller the particle size of the activated coal, the higher the percentage colour reduction.
It was also observed that the temperature has a large effect on the bleaching of palm using coal. This percentage colour reduction increase as the temperature increases.
It could be conclude that coal is a poor absorber though if activated properly can used as a bleasching.
Synthesis of coal activated carbon from coal involves the production of activates carbon from coal and the use of it as on adsorbent or adsorptive material which is used in bleaching processes.
An adsorptive material or adsorbent is this a solid which is able to adsorb a considerable amount of gas or liquid. The gas or liquid been adsorbed is referred to as the adsorbed. Adsorbed material may occur nature all or may be prepared synthetically.
The naturally occurring carbonados material such as coal, wood, coconut shell or bones are decomposed in an inert atmosphere at a temperature of about 500k. the product will not be porous so it will need additional treatment or activation to generate a system of fine pores. The carbon can be produced in the activated state by treating the raw material with chemical like zinc chloride or phosphoric acid before carbonizing.
Activated carbon has a surface area, typically of 106 m2/kg mostly associated with a set of pores about 2nm in diameter. Though there is likely to be another set of pores about 100nm in diameter, not contributing much the surface area.
Activated carbon may be used as a powder, in which from it is mixed in with the liquid to be treated, and then removed by filtration. It is also be used in granular form.
Hence by carefully choosing the starting material and the activated process it can be possible to generate in carbon a pore system with a narrow spore of pore size. This activated carbon can be synthesized from coal.