Tobacco Waste Liquid-Based Organic Fertilizer Particle for Controlled-Release Fulvic Acid and Immobilization of Heavy Metals in Soil

Abstract

Every year, a large amount of tobacco waste liquid (TWL) is discharged into the environment, resulting in serious pollution for the environment. In this work, a TWL-based particle (OACT) was fabricated by CaO, attapulgite (ATP), and TWL, and, then, OACT was coated by amino silicon oil (ASO) to form OACT@ASO. Therein, OACT@ASO had high controlled-release ability for fulvic acid (FA), because of the nanonetworks structure for ATP and the high content of FA in TWL. The release ratio (RR) of FA from OACT@ASO reached 94% at 75 h in deionized water, and 23% at 32 d in silica sand. Furthermore, the release mechanism of FA from OACT@ASO was consistent with the First-order law. Additionally, OACT@ASO also possessed high immobilization capacity for Cu(II), Cd(II), and Pb(II) (CCP) in soil. Notably, a pot experiment indicated that OACT@ASO could facilitate the growth of pakchoi seedlings and decrease the absorption of CCP by pakchoi seedlings. Thus, this study provides a new kind of organic fertilizer which could not only release FA, but also immobilize CCP in soil.

Alkali-Activated Potassium Persulfate Treatment of Sugarcane Filter Cake for the Rapid Production of Fulvic-like-Acid Fertilizer

“…As shown in Figure 1D, the effect of coexisting ions on the FLA content was also investigated. The FLA content decreased significantly after the addition of SO , which was disadvantageous for the generation of FLA. 24 The FLA content decreased significantly in the existence of Cd 2+ and Zn 2+ , probably because Cd 2+ and Zn 2+ could be chelated by FLA, which would influence the detection of FLA. 25 Subsequently, the existence of FLA could be confirmed by 3D-EEM, and its characteristic peak positions were located at E x /E m = 230−250/370−430 nm. 8,26 As shown in Figures 1E,F the content of FLA increased after CH-PS treatment, and thus CH-PS was beneficial for the humification of sucrose and the generation of FLA. (5)…”

“…In addition, the free radicals could be quenched by CO 3 2– , which was disadvantageous for the generation of FLA . The FLA content decreased significantly in the existence of Cd 2+ and Zn 2+ , probably because Cd 2+ and Zn 2+ could be chelated by FLA, which would influence the detection of FLA …”