Porosity Development on Activation of Char from Dry and Wet Babbool Wood

Satish Manocha,Vanraj B. Chauhan,L.M. Manocha 한국탄소학회 2002 Carbon Letters Vol.3 No.3

It is well known that the porosity and adsorption capacity in a carbon depends on the nature of precursor, pyrolysis and activation conditions and the ash content. The studies on carbon prepared from the dry and wet babbool wood were under taken to ascertain the effect of initial state of precursor on the development of porosity in the resulting activated carbon. The characterization and adsorption studies carried out shows the presence of mainly mesoporosity in the carbon prepared from dry wood while more of microporosity was observed in the activated carbon prepared from wet wood. The results on porosity in both the cases have been compared and correlated with their processing conditions.

Silver Up-Take by Modified Pitches

Manocha, Satish M.,Patel, Mitesh Korean Carbon Society 2002 Carbon Letters Vol.3 No.1

The modification of coal-tar pitch has been carried out by heat treatment of pitch at different temperatures in the range ($300^{\circ}-400^{\circ}C$) for different times (2-5 hrs) in air and nitrogen. The pitch heat treated in air at lower temperature ($300^{\circ}C$) exhibit increase in softening point by $20^{\circ}C$ as compared to only $2^{\circ}C$ when treated in nitrogen. The changes are faster in air than in pure nitrogen. Pitch as such as well as after heat treatment were further treated with metal complexes by solution route. Silver intake has been found to increase from 0.5 to 0.8 % in nitrogen treated pitch while the uptake is found to decrease for pitches treated in air at $350^{\circ}C$ for 5 hrs. Experiments have also been made to incorporate silver into PAN and PAN-ox fibers through solution route. The metal intake has been found to be more in PAN-ox fibers than in PAN as such. Metal loaded carbon composites have been made by using metal loaded fibers as well as cokes. These composites as such exhibit higher surface oxygen complexes but decrease after activation.

Studies on Development of Porosity in Carbon from Different Types of Bio-wastes

Manocha, Satish M.,Chauhan, Vanraj B.,Manocha, L.M. Korean Carbon Society 2002 Carbon Letters Vol.3 No.1

The regional bio-wastes available in abundance in India were converted into porous carbon by heat treatment at different temperatures from $650-950^{\circ}C$. The wood retain shapes after pyrolysis though shrinkage occured both in axial and radial directions. The shrinkage in radial direction was found to be more than in axial direction in all woods. The density of woods and chars from these at a given temperature has been found to follow linear relationship. Chars were steam activated at temperature $700-800^{\circ}C$ for different times between 45-240 min. Both the temperature and time of activation with steam has a profound effect on surface area. Chars from softwoods like bagasse and castor oil plant were activated at lower temperature, i.e. $700-750^{\circ}C$ whereas hard wood chars have to be activated at higher temperature around $800^{\circ}C$. The morphology of wood as well as of chars has been studied by SEM. The comparison of the two showed that the nature of porosity in chars depends on precursor morphology, nature and physical state of wood and presence of inorganic compounds in the wood. Hard wood results in cross inter connected pores while softwood leads to fibriller structure. The present studies show that activated carbon with reasonably good surface area (${\sim}1000m^2/gm$) can be prepared from soft wood bio-wastes like bagasse and castor oil plant, while surface area ${\sim}1370m^2/gm$ was achieved from hard wood bio waste of pine wood.

Porosity Development on Activation of Char from Dry and Wet Babbool Wood

Manocha, Satish,Chauhan, Vanraj B.,Manocha, L.M. Korean Carbon Society 2002 Carbon Letters Vol.3 No.3

It is well known that the porosity and adsorption capacity in a carbon depends on the nature of precursor, pyrolysis and activation conditions and the ash content. The studies on carbon prepared from the dry and wet babbool wood were under taken to ascertain the effect of initial state of precursor on the development of porosity in the resulting activated carbon. The characterization and adsorption studies carried out shows the presence of mainly mesoporosity in the carbon prepared from dry wood while more of microporosity was observed in the activated carbon prepared from wet wood. The results on porosity in both the cases have been compared and correlated with their processing conditions.

Studies on Pyrolysis Behaviour of Banana Stem as Precursor for Porous Carbons

Manocha, Satish,Bhagat, Jignesh H.,Manocha, Lalit M. Korean Carbon Society 2001 Carbon Letters Vol.2 No.2

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

Silver Up-Take by Modified Pitchs

Satish M.Manocha,Mitesh Patel 한국탄소학회 2002 Carbon Letters Vol.3 No.1

Porosity Development in Activation of Char from Dry and Wet Babbool Wood

Satish Manocha,Vanraj B. Chauhan,L.M.Manocha 한국탄소학회 2002 Carbon Letters Vol.3 No.3

Studies on Pyrolysis Behaviour of Banana Stem as Precursor for Porous Carbons

Satish Manocha,Jignesh H. Bhagat,Lalit M. Manocha 한국탄소학회 2001 Carbon Letters Vol.2 No.2

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to 1000℃. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above 700℃ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.

Studies on Development of Porosity in Carbon from Different Types of Bio-wastes

Satish M. Manocha,Vanraj B. Chauhan,L.M. Manocha 한국탄소학회 2002 Carbon Letters Vol.3 No.1

The regional bio-wastes available in abundance in India were converted into porous carbon by heat treatment at different temperatures from 650-950℃. The wood retain shapes after pyrolysis though shrinkage occured both in axial and radial directions. The shrinkage in radial direction was found to be more than in axial direction in all woods. The density of woods and chars from these at a given temperature has been found to follow linear relationship. Chars were steam activated at temperature 700-800℃ for different times between 45-240 min. Both the temperature and time of activation with steam has a profound effect on surface area. Chars from softwoods like bagasse and castor oil plant were activated at lower temperature, i.e. 700-750℃ whereas hard wood chars have to be activated at higher temperature around 800℃. The morphology of wood as well as of chars has been studied by SEM. The comparison of the two showed that the nature of porosity in chars depends on precursor morphology, nature and physical state of wood and presence of inorganic compounds in the wood. Hard wood results in cross inter connected pores while softwood leads to fibriller structure. The present studies show that activated carbon with reasonably good surface area (~1000m2/gm) can be prepared from soft wood bio-wastes like bagasse and castor oil plant, while surface area ~1370m2/gm was achieved from hard wood bio waste of pine wood.