摘要
针对海藻酸钠凝胶(SA)材料在处理含铬废水时存在处理效果不理想、利用率低等问题,以海藻酸钠为原料,采用凝胶包埋法负载Ba^(2+)制备凝胶球SA-Ba,并添加聚乙二醇进行共价混和改性,得到聚乙二醇改性海藻酸钡凝胶材料(PEG-SA-Ba)。利用所制材料进行除铬试验,与传统的海藻酸钙(SA-Ca)凝胶球对比,考察3种凝胶球材料除铬效果以及pH、初始Cr(Ⅵ)浓度、PEG-SA-Ba投加量等参数对PEG-SA-Ba材料除铬效果的影响,并通过扫描电子显微镜(SEM)、傅里叶红外光谱(FTIR)对样品进行表征。结果表明:海藻酸钠与Ba^(2+)交联后得到的SA-Ba大大提高了SA的除铬效果,其除铬量是SA-Ca的800倍以上,经过共价改性后的PEG-SA-Ba为Cr(Ⅵ)的吸附提供了更多活性位点,除铬容量较未改性时提高了4.38 mg/g。随着pH的增加,PEG-SA-Ba对Cr(Ⅵ)的去除率也不断增大,p H为6时的除铬容量较pH为2时提高了16.24 mg/g,当pH超过8时,凝胶球结构不稳定易造成离子泄漏,导致在凝胶球之外有沉淀物生成。PEG-SA-Ba除铬容量随着Cr(Ⅵ)浓度增加而增加,随投加量增加而下降。SEM和FTIR表征分析验证了Ba^(2+)负载成功且聚乙二醇与海藻酸钠交联效果良好。PEG-SA-Ba凝胶球材料在制备成本和方式上均具有明显优势,材料成本分别比SA和SA-Ba节约了99%和24%。
Sodium alginate gel(SA)material has problems such as unsatisfactory treatment effect and low utilization rate in the treatment of chromium-containing wastewater.In order to solve these problems,sodium alginate was used as raw material,and gel balls(SA-Ba)were prepared by gel embedding method loaded with Ba^(2+),and polyethylene glycol was added for covalent mixing and modification to obtain polyethylene glycol modified barium alginate gel material(PEG-SA-Ba).Compared with the traditional calcium alginate(SA-Ca)gel ball,the chromium removal effect of the three gel ball materials and the effects of experimental parameters such as pH,initial Cr(Ⅵ)concentration,and PEG-SA-Ba dosage on the chromium removal effect of PEG-SA-Ba materials were investigated,and the samples were characterized by scanning electron microscopy(SEM)and Fourier infrared spectroscopy(FTIR).The results showed that:SA-Ba crosslinked with sodium alginate and Ba^(2+)greatly improved the chromium removal effect of SA,and the chromium removal amount was more than 800 times that of SA-Ca;the covalently modified PEG-SA-Ba provided more active sites for the adsorption of Cr(Ⅵ),and the chromium removal capacity was increased by 4.38 mg/g compared with that without modification.With the increase of pH,the removal rate of Cr(Ⅵ)by PEG-SA-Ba also continued to increase;the chromium removal capacity at pH 6 was 16.24 mg/g higher than that at pH 2,and when pH exceeds 8,the structure of the gel ball was unstable and easy to cause ion leakage,resulting in precipitate formation outside the gel ball.The chromium removal capacity of PEG-SA-Baincreased with the increase of Cr(Ⅵ)concentration and decreased with the increase of dosage.SEM and FTIRcharacterization verified that the Ba^(2+)loading was successful and the crosslinking effect of polyethylene glycol andsodium alginate was good.Finally,the discussion found that PEG-SA-BA gel ball materials had obvious advantagesin preparation cost and method,saving more than 99%and 24%of material costs compared with SA and SA-Ba,respectively.
作者
张羽嘉
王兴润
王雷
刘海
颜湘华
ZHANG Yujia;WANG Xingrun;WANG Lei;LIU Hai;YAN Xianghua(School of Environmental Science and Engineering,Nanjing Tech University;Chinese Research Academy of Environmental Sciences)
出处
《环境工程技术学报》
CAS
CSCD
北大核心
2023年第6期2135-2142,共8页
Journal of Environmental Engineering Technology
基金
国家重点研发计划项目(2018YFC1802200)。
