Preparation Of Bamboo-Based Actived Carbon And Its Application In Flue Gas Desulphurization

Bamboo resources are rich in China,covering about 1/5 of the total area of the bamboo forest,bamboo has advantages of short growth cycle,high output and growing quickly,having carbonized activation,bamboo turns into carbon materials with Developed porous structure,high mechanical strength.With good adsorption,catalytic and wear-resisting performance,bamboo-based activated carbon can efficient remove SO₂ in flue gas.Compared with coal activated coke and activated carbon fiber,bamboo-based activated carbon is a low-carbon renewable resource,so bamboo charcoal or the bamboo-based activated carbon for removal of SO₂ in the flue gas should receive attention.This paper takes Hunan Nanzhu as raw material,with steam and ammonia activator,studies the carbonized-activation conditions on bamboo-based activated carbon pore structure,surface chemical properties and its desulfurization performance.Examine the particle size of bamboo-based activated carbon,flue gas composition,space velocity and the desulfurization temperature influence on the desulfurization performance of bamboo-based activated carbon,and the flue gas desulfurization dynamics is also discussed.The results show that:1.Steam activation preparation,the yield of bamboo-based activated carbon is along with the increase of temperature carbonization,the change is not obvious.The Content of surface basic functional groups shows a trend that first increases and then decreases.And the content of sulfur capacity and basic functional groups have the similar change trends;Carbonization time has the similar influence on bamboo-based activated carbon as carbonization temperature;With the increase of activation temperature,the yield of bamboo-based activated carbon decreases gradually,the Content of surface basic functional groups shows a trend that first increases and then decreases.,sulfur capacity shows the similar trend,As time going on,the yield of bamboo-based activated carbon decreases gradually,but the content of surface basic functional groups and sulfur capacity increases;the yield of bamboo-based activated carbon decreases as the increase of activator flow,but surface basic functional group content and sulfur capacity increase gradually.2.Bamboo charcoal has fewer specific surface area,poorer desulphurization performance,as the bamboo-based activated carbon activated by steam and ammonia increases both.The pore structure formed by two kinds of the activation methods is similar,the surface carbon content of bamboo-based activated carbon has little difference,but oxygen and nitrogen content are obviously reduce respectively and increase.;After carbonization,XRD diffraction peak of cellulose becomes weak,the diffraction peak of graphite-like structure appeared,at the same time,the surface chemical structure had a drastic change,a large number of functional group disappeared,just peaks that wavelength were 1125 cm^-1,2311 cm^-1,2924 cm^-1 and 3430 cm^-1 kept,the intensity of the peak?002?and?10?become weak,5 kinds of wavelength of infrared peak all had certain increase,and formed a peak of wavelength is 1630 cm^-1;there were the same type of carbon,oxygen functional group on the surface of bamboo-based activated carbon activated by steam and ammonia,while XPS map of the latter showed the two N1s signal peak which showed at 398.3?398.9 eV to kind of pyridine as a representative of N-6 group,and which showed at 400.2?400.8EV to kind of pyrrole and amine class as a representative of N-5 groups,ammonium salf is formed by-COOH and NH₃,H₂O is removed in heating condition then form the carboxyl amide and nitriles kind of group,-OH conbined with NH₃ to form amine groups,in the high temperature NH₃ form the free radical such as H·,NH₂· and NH·,the structure of-NH-easily replace xanthenes in the ether oxygen,after dehydration class of pyridine or acridine moiety are formed in the carbon layer edge;Before and after the SO₂ adsorbed on the surface bamboo-based activated carbon,XPS shows the introduction of the N-6?398.3?398.9 eV?group had some catalytic activity for desulfurization,a high content of nitrogen group N-Q?protonated pyridine nitrogen,ammonium salt?appeared on the surface BAC4a that adsorbed SO₂,After thermal regeneration,the relative content of N-6 on the surface of BAC4b increased,while that of N-5,N-Q decreased;XPS spectrum chart of BAC-a?b and BAC4a,4 b that were through adsorption and desorption with SO₂ indicates that,BAC4 had better catalytic oxidation performance for SO₂ than BAC,and BAC4a had good desorption for SO₂ than BAC-a.3.Optimization experiment scheme that carbonization and activation conditions influence on yield,sulfur capacity,specific surface area,pore volume and pore size are:the D₂C₁B₂A₁,D₃C₁A₃B₁,D₃A₃C₂B₂,D₃C₃A₂B₃ and D₂A₂C₁B₃,carbonized temperature and time have little effect on the yield of nitrogen-containing bamboo-based activated carbon,sulfur capacity and pore volume,but change specific surface area,pore size a lot,and activation time and activation temperature impact the comprehensive performance of;the of yield bamboo-based activated carbon increases with ammonia concentration rises,decreases with activation temperature rises,the specific surface area increases respectively first and then decreases,and the pore volume decreases and then increases,activation time has the similar influence as the activation temperature;The best optimal range of activation conditions that activates bamboo-based activated carbon that used for removal SO₂ in flue gas is:8.48%to 14.53%of the ammonia concentration,activation temperature 850??900?,activating time 120min?150min.4.For nitrogen bamboo-based activated carbon desulfurization performance,desulfurization conditions exist,the optimal range of temperature is 90? to 100?,O₂ and H₂O concentration are 8%to 12%,and eliminating internal and external diffusion effects,under the conditions of 70 ??100 ?,temperature influence onthe desulfurization performance establish a kinetic equation r=63.434exp?21148.07/RT?c_SO₂,through the adaptability test,the adaptability for the range 70 ??80 ? is more remarkable than90 ??100?.