Magnetic Wakame-Based Biochar/Ni Composites with Enhanced Adsorption Performance for Diesel

In this study,the magnetic wakame biochar/Ni composites were prepared with three activating reagents of H_(3)PO_(4),ZnCl_(2) and KOH by one-step pyrolysis activation,characterized by BET,SEM,TEM,FI-IR,XRD,Raman,and elemental analyzer,and their adsorption performance for diesel were also analyzed.The results showed that wakame biochar/Ni composites had larger specific surface area,abundant porous structure,and various reactive groups,rendering its enhancement of adsorption efficiency.The adsorption experiments indicated that the maximum adsorption capacities for diesel using WBPA 0.5,WBHZ 0.5 and WBPH 0.5 were 4.11,8.83,and 13.47 g/g,respectively.The Langmuir model was more suitable for the adsorption isotherms process,and the Pseudo-second-order model could better describe the adsorption kinetic experimental.And the magnetic wakame biochar/Ni composites presented good stability and recyclability.This study provides a novel pattern for the high-value utilization of wakame,having huge potential in the treatment of oily wastewater.

Preparation of Activated Carbon Based on Straw and Its Adsorption on Sunset Yellow

The removal effect of sunset yellow by the activated carbon prepared by modified straw was studied, and the effects of adsorption temperature, adsorption time, adsorption capacity, solution salinity and solution pH on the removal effect of sunset yellow were analyzed. After being soaked in acid and alkali, the stalks and leaves of the straw were carbonized and modified at 200-700 ℃. The results show that the adsorption effect of the leaves soaked in alkali was the best when the carbonization temperature was 700 ℃. As the adsorption temperature was 30-40 ℃, the adsorption effect of sunset yellow was the best. With the increase of adsorption time, the removal rate of sunset yellow first increased, then decreased, and finally rose again. The first critical point was about 30 min. When the dosage of activated carbon was 0.7 g, the adsorption effect of 50 ml of sunset yellow solution was the best. The optimal solution salinity was 60%. pH had a small effect on the adsorption of sunset yellow, showing a fluctuating trend.

Modulating the degree of O vacancy defects to achieve selective control of electrochemical CO_(2) reduction products

Conversion of CO_(2) into high-value products using electrochemical CO_(2) reduction(ECR)technology is an effective way to alleviate global warming and reach carbon neutrality.The oxygen vacancies in heterogenous catalysis are generally considered as a powerful method to enhance the performance of ECR by promoting CO_(2) adsorption and activation.However,the extent of defects in oxygen vacancies-activity relation has rarely been studied.Herein,we prepared Cu-Cd bimetallic catalysts with adjustable oxygen defect degree by controlling the amount of cadmium addition.Fourier transform infrared spectroscopy characterization results reveal that the formation of oxygen vacancies is attributed to the asymmetric stretching of Cu-O by the addition of cadmium.Electrochemical results show that the oxygen defect degree can modulate the selectivity of ECR products.A low degree of oxygen defects(CuO)is generally associated with lower product Faraday efficiency(FE_(C2)/FE_(C1)≈114%),but overabundant oxygen vacancies(CuO_(2.625)-CdO_(0.375))are not entirely favorable to improving ECR activity(FE_(C2)/FE_(C1)≈125%)and single selectivity,while an appropriate degree of oxygen vacancies(CuO_(2.75)-CdO_(0.25))can facilitate the ECR process toward single product selective production(FE_(C2)/FE_(C1)≈296%).The theoretical calculation showed that the O vacancy formed on CuO and the interface between CdO and CuO were conducive to enhancing the formation of ^(*)COOH intermediate and promoting the generation of ethylene products.This study provides a new approach and insight into the selective production of single products for future industrial applications of ECR.