Comparative study of the influence of linear and branched alkyltrichlorosilanes on the removal efficiency of polyethylene and polypropylene-based microplastic particles from water

Removal of Microplastics from Waters through Agglomeration-Fixation Using Organosilanes—Effects of Polymer Types, Water Composition and Temperature

“…Facing this challenge, Herbort et al 2016 developed a new approach to remove microplastics from water using organosilanes ( Figure 1) [24][25][26][27][28]. The organosilanes consist of one organic group and three reactive groups.…”

“…In the second step of the fixation, the three reactive groups form a solid hybrid silica gel that includes and fixes the microplastics chemically driven by a water induced sol-gel process. During this sol-gel process, the reactive groups are hydrolyzed to highly reactive silanols, which subsequently condensate and form siloxane bonds [27,29].…”

“…In the second step of the fixation, the three reactive groups form a solid hybrid silica gel that includes and fixes the microplastics chemically driven by a water induced sol-gel process. During this sol-gel process, the reactive groups are hydrolyzed to highly reactive silanols, which subsequently condensate and form siloxane bonds [27,29]. The novelty of this process is the combination of a physical agglomeration process with a water induced chemical fixation process, leading to strong particle growth and stable agglomerates [25,26].…”

“…Hence, the organic groups can be adapted to different polymer types and surface chemistries. The reactivity of the organosilanes can be adapted to different water compositions by changes in reactive groups and organic groups [26,27]. The high diversity and adaptability of organosilanes as chemical substance class gives this relatively new and little researched approach a high potential for application in water treatment and microplastic removal.…”

“…So far the process has been tested to remove polyethylene and polypropylene based microplastics on lab scale using demineralized water and on pilot plant scale from tap water [25,27]. To investigate the transferability to processes in sea water and wastewater, it is tested how water compositions affect the removal process, as dissolved ions, natural organic matter or surfactant compounds can affect the sol-gel process and thus the removal process [28].…”