Plasma polymerized allylamine functionalization of quartz particles for the removal of anionic water contaminants

Summary form only given. Contaminated water is a worldwide problem and can lead to a number of serious health problems. Although there are a number of water purification techniques available, the majority of these are only used in highly populated areas of developed countries. Water purification in rural areas, disaster zones and developing countries is of major concern. Decentralized water treatment can be effectively used in these areas, and do not require the energy and personnel of centralized water treatment. A simple and cheap decentralized water treatment system is being investigated via plasma polymerization of low cost adsorbents. A rotating barrel inductively coupled radio frequency plasma reactor and allylamine monomer were used to functionalize the surface of quartz particles with amine groups. The addition of amine functional groups produces surfaces with higher isoelectric points which are predominately positively charged in solution thus enabling the removal of anionic contaminants via electrostatic attraction. Removal of anionic contaminants humic acid, acid orange 7 and bovine serum albumin were investigated. Plasma power, allylamine flow rate and polymerization time were varied to determine the conditions for optimal humic acid removal. The effect of polymerization time on surface chemistry and charge was investigated via X-ray photoelectron spectroscopy, time of flight secondary ion mass spectrometry and electrokinetic analysis. Optimal humic acid removal was achieved at a power of 25 W and an allylamine flow rate of ≈ 4.7 sccm. Polymerization time was varied and maximum humic acid removal was observed for a polymerization time of 30 minutes. Acid orange 7 removal was highly dependent on pH and initial concentration. Maximum removal was achieved for a polymerization time of 60 minutes. Bovine serum albumin could also be successfully removed via plasma polymerized allylamine coated quartz particles. Functionalization of quartz particles vi- plasma polymerized allylamine has shown to successfully remove a number of anionic water contaminants. Investigation of additional coatings and contaminants will assist in the development of a low cost water treatment system.