Tannic Acid and Ferrous Sulfate Modified Kapok Fiber for Oil-water Separation

• Published in: Fibers and polymers Vol. 23; no. 11; pp. 3058 - 3067
• Main Authors: Ke, Guizhen, Chen, Shuhui, Tang, Jiani, Li, Huanmin, Liu, Keshuai
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Fiber Society 01.11.2022; Springer Nature B.V
• Subjects: Absorption; Acids; Biodegradability; Carbon tetrachloride; Chemistry; Chemistry and Materials Science; Contact angle; Ferrous ions; Hexanes; Hydrophobicity; Infrared analysis; Iron sulfates; Oil spills; Polymer Sciences; Separation; Sorbents; Tannic acid; Vegetable oils; Tannic acid; Oil absorption material; Kapok fiber; Ferrous sulfate; Hydrophobicity
• ISSN: 1229-9197; 1875-0052
• DOI: 10.1007/s12221-022-0458-y

Biodegradable oil absorbing materials have attracted extensive attention in dealing with oil spill pollution. To develop more excellent oleophilic oil sorbent, the combination of tannic acid and ferrous sulfate was employed to treat the renewable and biodegradable natural kapok fiber. The as-prepared kapok showed superhydrophobic characteristics with high water contact for the formation of tannic acid and ferrous ion complex on kapok surface, which was confirmed by scanning electron microscopy observation and infrared spectroscopy and X-ray diffraction analysis. The preparation process of the modified kapok fiber was optimized. When the sodium chlorite pretreated kapok fiber was firstly treated with 4.25 g/ l tannic acid and subsequently immersed in 4.25 g/ l tannic acid and 6.25 g/ l ferrous sulfate mixture at 60 °C for 15 min, the asprepared kapok fiber presented the best oil absorption capacity and hydrophobicity (water contact angle 150.7 °). The treated kapok had good adsorption capacity for oils and organic solvents, 48.2, 41.6, 53.4, 52.8, 49.2, 41.2 g/g for vegetable oil, diesel oil, silicone oil, carbon tetrachloride, DMF and n-hexane, respectively. In addition, the tannic acid and ferrous sulfate treated kapok was recycled for six times through simple mechanical squeezing, and showed good oil-water separation performance oil, indicating its potential application in the removal of spilled oil on water.