Studies On The Production Of Activated Carbon By Rice Husk And Its Applications In Pruducing Biodiesel

Activated carbon is an adsorbent with strong adsorption capacity,stable chemical properties,high mechanical strength,excellent chemical resistance and other characteristics.Making activated carbon is widely used in medicine,food,transportation,agriculture,national defense,environmental protection and chemical industry and other aspects of human life.Rice husk is the most important by-products,it's main components are wood fibe and silicon,the active ingredient preparation of activated carbon.However,due to the accumulation of low density,difficult to degrade,as well as long-term accumulation of spontaneous combustion and environmental pollution,it's interesting to look into the comprehensive utilization of rice husk.Therefore,how to more effectively utilize rice husk for deep processing of agricultural products,turning waste into treasure,reducing environmental pollution are of great significance.In this study,the ionic liquid swelling rice husk fiber were done;using composite activation method to produce husk-based activated carbon and investigating and determine activation parameters;using SEM to study the activation parameters by pictorial diagram;using activated to produce carbon supported catalyst,catalyzing to produce biodiesel.The details of the study are as the following:?1?Different ionic liquids have different effects on rice husk fibers,the effect of[Epy]NO₃ on rice husk fibers is swellon,while effect of [Amim]Cl,[Bmim]Cl and[Emim]Ac are dissolution and degradation.Using microwave treatment,the silicon content of rice husk,microwave power,temperature and microwave time have significant impacts on treatment with ionic liquids on rice husk fibers.Without desilication process,the rice husk has not changed on surface structure in four ionic liquid,while with desilication process,the rice husk occurred dissolving and swelling.When the silicon content is 0.3073%,the rice husk fibers occurred dissolving and degradating obviously,and when the silicon content is 4.519%,the rice husk fibers occurred swelling in [Epy]NO₃.When selecting [Epy]NO₃,the degree of swellon of rice husk fibers increases with the increasing of microwave powe and temperature,but microwave time has little effect.The optimal parameters of swellon of rice husk fibers by [Epy]NO₃ is: silicon content is 4.519%,microwave power is 240 W,microwave temperature is 60 ?,microwave time is 30 min.When using SEM to observe the rice husk swelled by [Epy]NO₃,a lot of "gully" and porosity can be seen on the surface of rice husk.?2?Using rice husk treated by ionic liquid as raw materials,phosphoric acid and zinc chloride as an activator compound,“one-step”preparation of activated carbon,"methylene blue adsorption" and "iodine adsorption" as an indicator parameter to evaluate the performance of activated carbon adsorption.Using the single factor to investigate the effect of silicon content,activation and time,solid-liquid ratio,the activator compound ratio,carbonization temperature and time on preparation technology.By orthogonal experiments,using seven factors and three levels of law to determine the optimum process parameters: silicon content is 4.519%,activation temperature is 600 ?,activation time is 1h,solid-liquid ratio is 2.5,activator compound ratio is 2.5,carbonization temperature is 450?,carbonization time is 1h,the yield of activated carbon is 24.52%,methylene blue adsorption is 154.3mg/g and iodine adsorption is 1477mg/g.?3?Using pore structure in electron micrographs as an evaluation index of activated carbon adsorption performance,investigating the effect of silicon content,activation temperature,activation time,solid-liquid ratio,the activator compound ratio,carbonization temperature and carbonization time on the preparation technology,the results consistent with the above.?4?Using nitric acid to modificate the activated carbon,and the optimum condition is: mass fraction of HNO₃ is 1%,microwave power is 400 W,modification temperature is 40 ?,modification time is 2h,the methylene blue adsorption is136.5mg/g and iodine adsorption is 1343 mg/g;using sodium hydroxide as a catalyst and activated carbon as support to produce immobilized catalyst.Besides,using SEM to investigate the load effect.Using laboratory waste oil as raw materials,after refined,measuring acid value is 3.464,suiting for biodiesel preparation;using refined oil as raw materials and activated carbon-sodium hydroxide as a catalyst,investigating the effect of methanol to oil molar ratio,the amount of catalyst,reaction temperature and reaction time on the yield of biodiesel,by orthogonal experiment,the optimum condition is: oil molar ratio is 6:1,the amount of catalyst is 2.0g,reaction temperature is 55?,reaction time is 50 min,the yield of biodiesel is 93.86%.