Formulating and Optimizing a Novel Biochar-Based Fertilizer for Simultaneous Slow-Release of Nitrogen and Immobilization of Cadmium

Abstract

This study aimed to develop and optimize a novel biochar-based fertilizer composed of rice husk biochar and urea–hydrogen peroxide (UHP), which can simultaneously slowly release nitrogen and immobilize cadmium (Cd). Response surface methodology (RSM) was adopted to optimize the fertilizer formulation with the lowest nitrogen release rate. Under the optimized conditions, the cumulative nitrogen release rate of the biochar-based fertilizer was 17.63%, which was significantly lower than that of ordinary fertilizer. Elementary analysis, scanning electron microscopy (SEM) images, and Fourier transform infrared (FTIR) spectroscopy proved that UHP attached to the porous structures of the biochar. The adsorption test showed that the adsorption of Cd onto biochar-based fertilizer quickly reached equilibrium with an equilibrium adsorbing quantity (Qe) of 6.3279 mg·g−1 with an initial concentration of 10 mg·L−1. Compared to original biochar, the Cd immobilization ability of biochar-based fertilizer was significantly better. The adsorption of Cd on biochar-based fertilizer is mainly based on a monolayer adsorption behavior. Finally, improved crop growth was demonstrated by pot experiments, which showed a significant increase in the biomass of cabbage. The concept and findings presented in this study may be used as references in developing a novel biochar-based fertilizer for simultaneously enhancing crop yield and reducing environmental risk.

Properties of Biochar from Anaerobically Digested Food Waste and Its Potential Use in Phosphorus Recovery and Soil Amendment

“…Interestingly, the application of biochar in agriculture can be an effective way to enhance soil fertility, as it may contain multiple minerals that are required for soil enrichment. Chen et al [21] reported the addition of biochar produced from cow dung to agricultural soil, and confirmed that P-laden biochar not only increased the germination rate, but also promoted plant growth. However, to the best of our knowledge, only limited information is available on the utilization of phosphorus from biochar produced from food waste-derived biomass.…”

Optimized Use of Ferric Chloride and Sesbania Seed Gum (SSG) as Sustainable Coagulant Aid for Turbidity Reduction in Drinking Water Treatment

“…Moreover, the p-value of lack of fit (0.0709) in this model implies that the lack of fit was not significant. The insignificance of lack of fit indicated that the proposed model fit the experimental data and the independent variables or parameters have considerable effects on the response [19]. To summarize, the R 2 and the insignificant lack of fit have proven the reliability of the model.…”

“…This approach overcomes the limitation of the traditional one-factor-at-a-time-method, where the interaction between the factors is hard to identify [17,18]. In this experiment, the Box-Behnken design (BBD), as the standard design of RSM [19], was adopted to statistically optimize the influencing factors and evaluate the effect of the influencing factors on the turbidity reduction in drinking water treatment. The dosage of FeCl 3 , dosage of SSG, and the settling time were chosen as the influencing factors.…”

“…Turbidity reduction (%) in drinking water treatment was chosen as the response Y and a design matrix consisting of 15 experimental runs, including three replicated runs in the center, was constructed. The response data were further analyzed by multiple regression to fit the quadratic polynomial model [19], as illustrated in Equation 2.…”

The Prospective Approach for the Reduction of Fluoride Ions Mobility in Industrial Waste by Creating Products of Commercial Value

“…According to literature [12,[19][20][21][22][23][24], the content of toxic ions can be reduced in two ways: by removing them from waste or by reducing their mobility in the environment-immobilization.…”