摘要
1,3-丙二醇是一种重要的化工原料,生物发酵法生产1,3-丙二醇往往会产生副产物2,3-丁二醇,限制了生物基1,3-丙二醇的进一步工业化应用。1,3-丙二醇与2,3-丁二醇亲水性强,导致其在低浓度发酵液中分离困难。基于2,3-丁二醇比1,3-丙二醇具有长的碳链和大的极化率,本文采用含有―Cl基团(憎水且具有大的极化率)的ZIF-71吸附分离水中低浓度的2,3-丁二醇/1,3-丙二醇。结果表明,ZIF-71对双组分2,3-丁二醇/1,3-丙二醇(50 g/L,50 g/L)中2,3-丁二醇的静态竞争吸附容量为123.6 mg/g,对2,3-丁二醇/1,3-丙二醇分离选择性高达7.6,分离效果优于沸石材料Beta。在3次循环吸附-解吸实验中ZIF-71依旧保持着稳定的结构和对2,3-丁二醇的选择性吸附能力。通过分子模拟,揭示了ZIF-71对1,3-丙二醇和2,3-丁二醇的吸附分离机制。ZIF-71与1,3-丙二醇之间主要通过弱的范德华力作用;而ZIF-71与2,3-丁二醇之间则是通过强的范德华力与弱的氢键协同作用,从而对2,3-丁二醇产生选择性吸附。可以看出,ZIFs材料有望成为选择性吸附分离低浓度副产物2,3-丁二醇的吸附剂,推动生物法制1,3-丙二醇的工业化发展。
1,3-Propanediol is an important chemical material,and the production of 1,3-propanediol bybiological fermentation often produces 2,3-butanediol,which limits the further industrial application ofbio-based 1,3-propanediol. 1,3-Propanediol and 2,3-butanediol have strong hydrophilicity,which makes itdifficult to separate in low-concentration fermentation broth. ZIF-71 containing group —Cl(hydrophobicityand large polarizability) is selected to adsorb and separate 2,3-butanediol/1,3-propanediol from diluteaqueous solutions since 2,3-butanediol has a longer carbon chain and larger polarizability than1,3-propanediol. The results show that the binary competitive adsorption capacity of ZIF-71 for 2,3-butanediol is 123. 6 mg/g,the binary competitive separation selectivity for 2,3-butanediol/1,3-propanediol isup 7. 6 and is better than Beta. In the three-cycle adsorption and desorption experiments,ZIF-71 stillmaintains a stable structure and selective adsorption for 2,3-butanediol. We reveal the separation mechanismof ZIF-71 for 1,3-propanediol and 2,3-butanediol through molecular simulation. The interaction betweenZIF-71 and 1,3-propanediol is mainly through weak van der Waals force;while the interaction between ZIF-71 and 2,3-butanediol is through the synergistic effect of strong van der Waals force and weak hydrogenbonding,which causes the selective adsorption of 2,3-butanediol by ZIF-71. Therefore,ZIFs materials areexpected to be candidate adsorbents for the selective adsorption and separation of by-product 2,3-butanediolfrom dilute aqueous solutions,which promotes the industrialization of biological production of 1,3-propanediol.
作者
张健爽
高美珍
王梦瑶
石琪
董晋湘
ZHANG Jian-Shuang;GAO Mei-Zhen;WANG Meng-Yao;SHI Qi;DONG Jin-Xiang(Taiyuan University of Technology,Taiyuan 030024,China)
出处
《应用化学》
CAS
CSCD
北大核心
2022年第11期1735-1745,共11页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(No.21822808)资助。
