Tian Guangyan, Wang Wenbo, Zhu Yongfeng, Zong Li, Kang Yuru, Wang Aiqin
Key Laboratory of Clay Mineral Applied Research of Gansu Province, Center for Eco-Material and Green Chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Key Laboratory of Special Function Materials for Ecological Environment and Information, Hebei University of Technology, Ministry of Education, Tianjin 300130, China.
Materials (Basel). 2018 Jan 6;11(1):86. doi: 10.3390/ma11010086.
Activated clay minerals have been widely used in the edible oil refining industry for decolorization of crude oil by adsorption, and so far many methods have been used to improve their decolorization efficiency. Herein, we successfully prepared a series of carbon/attapulgite (C/APT) composite adsorbents by a one-step in-situ carbonization process with natural starch (St) as the carbon source. It has been revealed that the adsorbent had better decolorization efficiency for crude palm oil than acid-activated APT. However, more than a million tons of decolorized waste is produced every year in the oil-refining industry, which was often treated as solid waste and has not yet been reutilized effectively. In order to explore a viable method to recycle and reuse the decolorant, the waste decolorant was further prepared into new C/APT adsorbents for the removal of dyes from wastewater, and then the dyes adsorbed on the adsorbent were used as the carbon sources to produce new C/APT adsorbents by a cyclic carbonization process. The results showed that the adsorbents prepared from the decolorized waste could remove more than 99.5% of the methylene blue (MB), methyl violet (MV), and malachite green (MG) dyes from the simulated wastewater with the dye concentration of 200 mg/L, and the C/APT-Re adsorbent consecutively regenerated five times using the adsorbed dyes as a carbon source still exhibit good adsorption efficiency for dyes. As a whole, this process opens a new avenue to develop efficient decolorants of palm oil and achieves recyclable utilization of decolored waste.
活性粘土矿物已广泛应用于食用油精炼工业中，通过吸附作用对原油进行脱色，迄今为止，人们已采用多种方法来提高其脱色效率。在此，我们以天然淀粉（St）为碳源，通过一步原位碳化法成功制备了一系列碳/凹凸棒石（C/APT）复合吸附剂。结果表明，该吸附剂对毛棕榈油的脱色效果优于酸活化凹凸棒石。然而，炼油行业每年产生超过一百万吨的脱色废料，这些废料通常被当作固体废弃物处理，尚未得到有效再利用。为了探索一种可行的脱色剂回收再利用方法，将废脱色剂进一步制备成新型C/APT吸附剂用于去除废水中的染料，然后将吸附在吸附剂上的染料作为碳源，通过循环碳化法制备新型C/APT吸附剂。结果表明，以脱色废料制备的吸附剂能够从浓度为200mg/L的模拟废水中去除超过99.5%的亚甲基蓝（MB）、甲基紫（MV）和孔雀石绿（MG）染料，并且以吸附的染料作为碳源连续再生五次的C/APT-Re吸附剂对染料仍具有良好的吸附效率。总体而言，该工艺为开发高效的棕榈油脱色剂开辟了一条新途径，并实现了脱色废料的可回收利用。
