Preparation of Activated Carbon From Sunflower Straw by H3PO4 Activation and Its Application for Acid Fuchsin Adsorption

In this work, sunflower straw (SS) was used as the raw material, H3PO4 was used as the activator, and the sunflower straw activated carbon (SSAC) was prepared by the one-step activation method under the impregnation ratio of 1:1, 1:2, 1:3, 1:5 (SS/H3PO4, g/g). The adsorption of acid fuchsin (AF) simulated dye wastewater by SSAC prepared under different immersion ratios has been studied. As the impregnation ratio increases, the pore structures of SSAC changed greatly. SSAC3 had the largest specific surface area (1794.01 m2/g), and SSAC4 had the smallest microporosity (0.0527 cm3/g) and the largest pore volume (2.549 cm3/g). The adsorption kinetics of four types of SSAC to AF were more in line with the quasi-second-order adsorption kinetic model. The Langmuir isotherm model was suitable for describing SSAC3 and SSAC4, and the Freundlich isotherm model was suitable for describing SSAC1 and SSAC2. Thermodynamics showed that the adsorption process was spontaneous and endothermic. At 303 K, SSAC4 showed a removal rate of 97.73% for 200 mg/L AF, and the maximum adsorption capacity of 2763.36 mg/g, which was the highest among the four types of SSAC. This study shows that the sunflower straw activated carbon prepared by the H3PO4 one-step activation method is a green and efficient carbon material and has great application potential in the treatment of dye-containing wastewater.

A novel and low-cost CuPc@C catalyst derived from the compounds of sunflower straw and copper phthalocyanine pigment for oxygen reduction reaction

A series of CuPc@C composite catalysts were prepared with uniform and stretchable sunflower straw biological materials as the carbon source and inexpensive copper phthalocyanine pigment as a nitrogen doping source.

Synergistic analysis of co-combustion of sunflower straw and coal gangue

Coal gangue and sunflower straw biomass from Xilingguole, Inner Mongolia, China and Ulanqab Tsining District, Inner Mongolia, China, respectively, were burned separately and mixed in different proportions. The synergistic effect was analyzed by comparing the actual mixed combustion curve with the theoretical mixed combustion curve. The bar chart and TR (the mean of the difference between the experimental and calculated was divided by the mean of the calculated values) value curve were used to show the synergistic effect. The results showed that the synergistic effect of coal gangue and sunflower straw was optimal when the ratio (sunflower straw:coal gangue) was 2:8.

Removal of Strontium Ions from Aqueous Solution by Sunflower Straw

The sorptive potential of sunflower straw (≤125 μm) for Sr2+ from aqueous solution was evaluated. Batch adsorption experiments were carried out as a function of solution pH, adsorbent dosage, Sr2+ concentration and contact time. FT-IR spectra and SEM of sunflower straw were employed to explore the functional groups available for the binding of Sr2+ and morphology of the adsorbent. Maximum uptake capacity of sunflower straw was 17.48 mg/g occurred at around pH 3-7. The adsorption equilibrium can be achieved within 5 min and kinetic data were fitted well to pseudo-second-order model. The Langmuir and Freundlich models were applied to describe isotherm sorption data. The Langmuir model gave an acceptable fit than Freundlich model.