Chetima Abba, Nde Bup Divine, Kewir Fannyuy, Wahaboua Abdoul
Department of Inorganic Chemistry, Faculty of Science, University of Maroua, Cameroon.
Department of Nutrition Food and Bio-resource Technology, College of Technology, University of Bamenda, Cameroon.
Heliyon. 2024 Jan 5;10(1):e24060. doi: 10.1016/j.heliyon.2024.e24060. eCollection 2024 Jan 15.
The decolorization of cottonseed oil with activated carbons (ACs) from neem and cotton husks has a dual interest: elimination of undesirable pigments in oil and valorization of the husks; by-products of neem and cottonseed processing, which would otherwise be dumped along riverbanks and farms causing environmental pollution. ACs were produced from neem and cottonseed husks after acid impregnation assisted by microwave heating and in ambient air for the decolorization of neutral cottonseed oil. The experimental data were analyzed by the intraparticle diffusion and the pseudo-second-order kinetic models as well as the Langmuir and Freundlich isotherm models. The method of impregnation and carbonization time had dramatic effects on the specific surface area (800-1500 g/m), the quantity of burn-off (50-70 %), and methylene blue index (300-5000 mg/g) values which indicated the potential of the prepared activated carbons in the bleaching of vegetable oil and in other applications such as environmental clean-up and in agriculture. Pigment adsorption increased with temperature for all ACs indicating that the decolorization process was endothermic. The quantity of adsorbent equally had a significant effect on the pigment adsorption process for all ACs. All the activated carbons prepared in this work were 30-80 % more efficient in pigment adsorption than bleaching earth that is normally used in decolorizing neutral cotton seed oil in industries. All tested models are adequate to describe pigment adsorption by the ACs. Both methods of preparation of ACs were effective for oil decolorization, but microwave impregnation is more appealing because it requires only 1 h compared to 6 h for ambient air. Optimum decolorization conditions were 90 °C for 40min and adsorbent concentration of 2 %.
去除油中不良色素以及使棉籽壳增值；印楝和棉籽加工的副产品，否则会被倾倒在河岸和农场造成环境污染。通过微波加热辅助酸浸渍并在环境空气中从印楝和棉籽壳制备活性炭，用于中性棉籽油的脱色。通过颗粒内扩散、准二级动力学模型以及朗缪尔和弗伦德里希等温线模型对实验数据进行分析。浸渍方法和碳化时间对比表面积（800 - 1500 g/m）、烧失量（50 - 70%）和亚甲基蓝指数（300 - 5000 mg/g）值有显著影响，这些值表明所制备的活性炭在植物油漂白以及环境清理和农业等其他应用中的潜力。所有活性炭的色素吸附量随温度升高而增加，表明脱色过程是吸热的。吸附剂的量对所有活性炭的色素吸附过程也有显著影响。本研究中制备的所有活性炭在色素吸附方面比工业上用于中性棉籽油脱色的漂白土效率高30 - 80%。所有测试模型都足以描述活性炭对色素的吸附。两种制备活性炭的方法对油脱色都有效，但微波浸渍更具吸引力，因为它只需1小时，而环境空气浸渍需要6小时。最佳脱色条件为90°C、40分钟和2%的吸附剂浓度。
