Research On The Preparation Of Carbon Materials By Acid Sludge Pyrolysis

Acid sludge is a by-product of oil chemical refining,which is rich in carbon.With low price and extensive resources,it has become a kind of good raw materials to make activated carbon.Chemical refining plays an important role in oil refining,and acid-base refining,one of chemical refinings,has the advantages of simple process,low equipment investment and operating cost.It can well remove something such as the colloid,alkaline nitrogen,sulfur,and most of the naphthenic acid non-hydrocarbon compounds in oil.But its produce acid residue caused serious environmental pollution and resource waste.Preparation of activated carbon by sludge pyrolysis is the environmental protection,and can bring economic benefits.This paper studies the three kinds raw material through physical activation and chemical activation to make activated carbon by orthogonal test and single factor optimization experiment.In physical activation,sulfuric acid residue in the preparation of activated carbon shows the best quality.Under the condition of 880℃,reaction time for 60min,steam flow rate of 2mL/min,it can produce activated carbon which has surface area of 985m²/g,pore volume of 0.54cm³/g and the average pore size of 2.1nm.In chemical activation,with the activation temperature of 800℃,activation time for 60min,alkali/carbon ratio of 2,the raw material can produce activated carbon which has specific surface area of 1986m²/g,hole volume of 1.03cm³/g,the average pore size of 2.1nm.By changing different conditions,it can produce activated carbon with different properties.Besides,the optimal activated carbon is chosen for adsorption of the heavy metal ions Cr⁶⁺.Experimental conditions consisted of acid and alkali environment,initial concentration and adsorption time have an influence on the adsorption capacity.In the condition of pH=2,the activated carbon show a good adsorption performance;when more than 40 min the adsorption has reached its equilibrium time.With the original solution of 50mg/L,the removal rate can reach more than 95%.Freundlich empirical formula fitting curve is more in line with the actual adsorption isotherm.