Page 188 - 《精细化工》2022年第1期
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第 39 卷第 1 期                             精   细   化   工                                  Vol.39, No.1
             2022 年 1 月                              FINE CHEMICALS                                  Jan.  2022


              水处理技术与环境保护
               废白土榴莲壳黏土生物炭的制备及其对 Cr(Ⅵ)的吸附



                                                           *
                                       李   燕,康新平 ,乔艳辉,陈梅芹
                                      (广东石油化工学院  化工学院,广东  茂名  525000)


                 摘要:以废白土与榴莲壳为原料制备了黏土生物炭吸附剂(SBEC),以废白土为原料制备了黏土炭基吸附剂
                 (SBE),并用于去除废水中的 Cr(Ⅵ)。用 SEM、XRD、FTIR、BET 对吸附剂进行了表征。考察了溶液初始 pH、
                 初始 Cr(Ⅵ)质量浓度、吸附剂投加量、吸附时间和吸附温度对 Cr(Ⅵ)吸附效果的影响。在 Cr(Ⅵ)初始质量浓度
                 为 100 mg/L、吸附剂投加量为 0.5 g/L、吸附时间 120 min、25  ℃条件下,SBEC 对溶液 pH 为 3 的 Cr(Ⅵ)去除
                 率最高为 86.1%,SBE 则在 pH 为 2 时去除率最高为 52.5%。SBEC、SBE 对 Cr(Ⅵ)的吸附过程符合准二级动力
                 学模型,SBEC 吸附过程符合 Freundlich 模型,SBE 则与 Langmuir 吸附等温线模型较符合;吸附行为是自发吸
                 热过程。经过 5 次吸附-脱附循环后,SBEC 对 Cr(Ⅵ)的去除率达 58.8%。
                 关键词:废白土;生物炭;吸附剂;动力学;热力学;水处理技术
                 中图分类号:X703      文献标识码:A      文章编号:1003-5214 (2022) 01-0178-09


                         Preparation of clay biochar from spent bleaching earth and

                                    durian shell and its adsorption for Cr(Ⅵ)


                                                         *
                                   LI Yan, KANG Xinping , QIAO Yanhui, CHEN Meiqing
                 ( College of Chemical Engineering, Guangdong University of Petrochemical  Technology, Maoming  525000,
                 Guangdong, China)

                 Abstract:  Clay-biochar adsorbent (SBEC)  and clay carbon-based adsorbent (SBE)  were prepared  using
                 spent bleaching earth and durian shell and then used to remove Cr(Ⅵ) from wastewater. These adsorbents
                 were characterized  by SEM, XRD,  FTIR  and BET. The effects  of initial pH  of solution, initial mass
                 concentration of Cr(Ⅵ), adsorbent dosage, adsorption time and temperature on the adsorption efficiency of
                 Cr(Ⅵ) were studied. Under the conditions of initial mass concentration of Cr(Ⅵ) of 100 mg/L, adsorbent
                 dosage of 0.5 g/L, adsorption time of 120 min and 25  ℃, the highest removal efficiency of SBEC for Cr(Ⅵ)
                 at pH =3 was 86.1%, and that of SBE at pH =2 was 52.5%. The adsorption process of Cr(Ⅵ) by SBEC and
                 SBE conformed to the  quasi-second-order kinetic model. The adsorption process  of  SBEC and SBE
                 accorded with Freundlich model and Langmuir isotherm model, respectively. The adsorption behavior of
                 SBEC and SBE for Cr(Ⅵ) in the simulated wastewater was a spontaneous and endothermic interaction. The
                 adsorption efficiency of SBEC was 58.8% after five adsorption-desorption tests.
                 Key words: spent bleaching earth; biochar; adsorbents; kinetics; thermodynamics; water treatment technology


                 皮革、电镀等行业产生大量含铬废水,其中                           间存在 5 种相互作用:物理吸附、静电作用、还原
            Cr(Ⅲ)和 Cr(Ⅵ)是最主要的形式。Cr(Ⅵ)对生物体具                     作用、络合作用、离子交换             [3-4] 。
                           [1]
            有致癌性和毒性 。Cr(Ⅵ)废水处理方法有吸附、氧                              Cr(Ⅵ)吸附剂的原料有生物炭、黏土矿物等,
            化还原、化学沉淀等。吸附法具有高效、操作简单、                            膨润土比表面积大、离子交换性能好、亲水性强,
                          [2]
            易再生等优点 。Cr(Ⅵ)在废水中常以 H 2 CrO 4 、                    可通过离子交换作用、表面络合作用和静电吸附作
                                                                                [5]
                        2–
                                2–
                 –
            HCrO 4 、Cr 2 O 7 和 CrO 4 形式存在,与各种吸附剂之              用吸附水中 Cr(Ⅵ) 。生物炭孔状结构丰富、表面

                 收稿日期:2021-05-29;  定用日期:2021-08-31; DOI: 10.13550/j.jxhg.20210541
                 基金项目:国家自然科学基金青年基金(41807337);广东省科技创新战略专项资金(2018S00145);茂名市科技计划(KJ033)
                 作者简介:李   燕(1969—),女,副教授,E-mail:liyanjia220@163.com。联系人:康新平(1971—),女,教授,E-mail:kxp330@163.com。
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