板栗苞生物炭的制备及其改性后对食用油中苯并[a]芘的吸附性能研究OA

To realize the high-value utilization of agricultural waste chestnut burs,an adsorbent material was prepared for the efficient removal of benzo[a]pyrene(BaP)from edible oils.Biochars were prepared from chestnut burs using different preparation processes,and the biochar with the optimal adsorption performance was selected for KOH activation.The effect of different mass ratios of biochar to KOH was investigated.The biochars before and after activation were characterized by BET,SEM,XRD,XPS,and FTIR.The adsorption mechanism of BaP was analyzed using kinetic and isotherm models,and the removal conditions were optimized in actual oil samples.The results showed that after KOH activation,the specific surface area of the biochar increased from 606.18 m2/g to 739.82 m2/g,with an increase in surface oxygen-containing functional groups and well-developed pore structures.The adsorption of BaP by the activated biochar followed the pseudo-second-order kinetic and Langmuir isotherm models.The maximum adsorption capacity calculated by the Langmuir model reached 467.80 mg/g,which was 36.44%higher than that of the unactivated biochar.Under the optimal conditions of temperature 110℃,adsorbent dosage 0.4%(mass fraction),and adsorption time 25 min,the removal rate of BaP from soybean oil reached 96.7%.This study provides a theoretical basis and technical reference for the resource utilization of agricultural waste and the safe purification of edible oils.