Preparation of magnetic hydrogel microspheres of lignin derivate for application in water

• Published in: The Science of the total environment 2019-10, Vol.685, p.847-855
• Main Authors: Meng, Yi, Li, Chengxiang, Liu, Xueqian, Lu, Jie, Cheng, Yi, Xiao, Ling-Ping, Wang, Haisong
• Format: Article
• Language: English
• Subjects: Chemical modification; Hydrogel microspheres; Lignin; Magnetic adsorbent; Water treatment
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2019.06.278

A low-cost and well-separated approach is introduced for adsorption pollutants in water. Chemical modified lignin is prepared with diethylenetriamine to enhance the reaction activities, then used to prepare lignin derivate magnetic hydrogel microspheres (LDMHMs) via blending with Fe3O4. The LDMHMs are successful prepared by the determination of FT-IR data, and the morphology shown from SEM imagine indicates the LDMHMs are in nanosized. The prepared LDMHMs are used as adsorbents for organic dyes, such as methylene blue (MB), methyl orange (MO) and malachite green (MG), the plateaus data are 43 mg/g, 39 mg/g and 155 mg/g, respectively. For inorganic pollutions, such as Pb2+, Hg2+ and Ni2+, the plateaus data are 33 mg/g, 55 mg/g and 23 mg/g, respectively. The adsorption data of unmodified lignin are 2.6 mg/g (Pb2+), 3.3 mg/g (Hg2+), 2.1 mg/g (Ni2+), 8 mg/g (MB), 10 mg/g (MG) and 2 mg/g (MO) in the same condition. The adsorbents are recycled by magnetic separation, regenerating from acid condition and reused for multiple cycles. The regeneration ratios are all above 90%, indicating a highly reusability and further reducing the cost of the treatment. [Display omitted] •Lignin is chemical modified to enhance the activities of absorbent.•The adsorbent is lower-cost, highly reusability and extensive adsorption range.•The adsorbents are well-separated by magnetic separation.•The method provides an approach of using industry byproduct to treat wastewater.