Design,Preparation And Application Of Bioresource-based Activated Carbon

Green Chemistry aims to be sustainable and is the guide for the development of the next generation of the chemical industry.Future non-renewable resources,such as the depletion of oil,coal,etc.,and the environmental pollution they cause must be effectively controlled.These issues have spurred our growing demand for renewable resources.Renewable resources are non-degradable,non-petroleum-based materials that pose lower risks to the health and safety of the environment and animals and plants.Among them,bagasse as a waste of the sugar industry has a wide range of sources,is non-toxic and safe,and has high biodegradability.Bagasse is mainly composed of natural polymers such as cellulose,hemicellulose and lignin,and has broad application prospects in water treatment applications.In this paper,sugarcane bagasse is used as raw material to prepare bagasse-based activated carbon adsorbent for removing Cr⁶⁺,and tetracycline hydrochloride in water by simple,low energy consumption and green preparation process.The main contents are as follows:The main works were summarized as follows:The utilization of bagasse as a raw material to prepare activated carbon adsorbents is an effective way to solve the water pollution problem,while achieving the goal of treating waste simultaneously.An effective activated carbon-based adsorbent was prepared from sugar cane bagasse with an one-step method of pyrolysis and Zn Cl₂activation for efficient Cr?VI?removal from water.Morphology,physicochemical properties and structure of the adsorbent samples were studied by Scanning Electron Microscope?SEM?,Energy Dispersive Spectroscopy?EDS?,X-Ray Diffraction?XRD?,N₂adsorption and desorption,Fourier Transform infrared spectroscopy?FT-IR?and X-ray Photoelectron Spectroscopy?XPS?.The batch and fixed bed adsorption experiments were adopted to confirm the one-step preparation of pyrolysis and Zn Cl₂during the activation process and to investigate the adsorption mechanism of Cr???.The maximum adsorption capacity was 80.880 mg g^-1,while the adsorption behavior fitted better with Freundlich equation and pseudo-second-order kinetics.These results confirmed that chemical adsorption is the strongest adsorption interaction during the adsorbing process of Cr???,and the adsorbents could effectively capture Cr?VI?to form monodentate and bidentate complexes.Adsorption and desorption performance and mechanism of tetracycline hydrochloride by activated carbon-based adsorbent derived from sugar cane bagasse activated with Zn Cl₂were studied by batch and fixed bed adsorption experiments,morphology characteristics and chemical properties analysis.The maximum adsorption capacity was 239.6 mg g^-1,and the adsorption behavior fitted better with Freundlich equation,pseudo second-order kinetics and intraparticle diffusion model in batch adsorption.The effects of flow rate,bed height,inlet concentration and temperature were studied in fixed bed adsorption,and adsorption data was fitted with six dynamic adsorption models,among which Dose Response model was most fitted with the breakthrough curve.Desorption breakthrough curves at different flow rates were determined by using anhydrous alcohol as the eluent.The adsorption and desorption mechanisms were inferred by analyzing the adsorption and desorption behavior data and physicochemical properties of the adsorbent.Tetracycline hydrochloride and activated carbon were bonded together by?-?interaction and cation-?bond.Ethanol was bound to the 10hydrogen bond acceptors on the tetracycline hydrochloride by hydrogen bonding to separate a portion of the tetracycline hydrochloride from the activated carbon.In summary,this paper is devoted to the use of renewable bioresources to prepare high-performance activated carbon with recyclable capacity for the treatment of pollutants in water bodies,such as Cr⁶⁺and tetracycline hydrochloride,through simple,low-energy preparation methods.This topic has a good application prospect in the field of water purification,and provides a good application example for the efficient use of agricultural waste.