National Engineering Research Center of Chemical Fertilizer Catalyst, School of Chemical Engineering, Fuzhou University, Fuzhou 350002, Fujian, PR China; School of Chemical Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China.
National Engineering Research Center of Chemical Fertilizer Catalyst, School of Chemical Engineering, Fuzhou University, Fuzhou 350002, Fujian, PR China; School of Chemical Engineering, Fuzhou University, Fuzhou 350116, Fujian, PR China.
J Hazard Mater. 2021 Jul 15;414:124906. doi: 10.1016/j.jhazmat.2020.124906. Epub 2021 Jan 13.
Corncob, an agricultural bio-waste, was used as adsorbent to remove organic and inorganic contaminants in waste lubricating oil (WLO) from diesel engine. To improve its adsorption capacity, corncob was modified with mixed solution of nitric acid, Hexadecyl trimethyl ammonium bromide and ethanol. Characterization results showed the crystallinity index of corncob enhanced 12%, which would be ascribed to the disruption of the dense lignin-carbohydrates structure in lignocellulose biomass by modification. The surface of modified corncob became smoother and porous. The adsorption results showed modified corncob had better removal rates to contaminants than raw corncob. For WLO with 80,000 km mileage, the removal rates to Fe, Al, Cu were enhanced from 19%, 6.4%, 48-27%, 27%, 53%, while that for oxide, sulphate, aromates, soot and insoluble resins were enhanced 1.7, 1.2, 3.0, 1.7 and 1.7 times. The reduction rate of total acid number to WLO with 40,000, 60,000, 80,000 km were enhanced 16%, 9%, 12% by modified corncob, respectively. The optimal adsorption condition was explored as adsorbing 60 min at 90 °C with 2% adsorbent. Corncob, with the advantages of low cost, good biodegradability and high adsorption capacity, could be used as alternative to conventional adsorbent for WLO.
玉米芯是一种农业生物废料，被用作吸附剂，以去除柴油机废润滑油 (WLO) 中的有机和无机污染物。为了提高其吸附能力，玉米芯用硝酸、十六烷基三甲基溴化铵和乙醇的混合溶液进行了改性。表征结果表明，玉米芯的结晶度指数提高了 12%，这归因于木质纤维素生物质中致密的木质素-碳水化合物结构被改性所破坏。改性后的玉米芯表面变得更加光滑和多孔。吸附结果表明，改性玉米芯对污染物的去除率高于原玉米芯。对于行驶里程为 80000 公里的 WLO，Fe、Al、Cu 的去除率分别从 19%、6.4%、48-27%、27%、53%提高到 65%、37%、72%、56%、72%，而氧化物、硫酸盐、芳烃、烟尘和不溶性树脂的去除率分别提高了 1.7、1.2、3.0、1.7 和 1.7 倍。行驶里程为 40000、60000、80000 公里的 WLO 的总酸值降低率分别提高了 16%、9%和 12%。改性玉米芯的最佳吸附条件为在 90°C 下吸附 60min，吸附剂用量为 2%。玉米芯具有成本低、生物降解性好、吸附能力强等优点，可用作废润滑油的传统吸附剂的替代品。
