Study On The Preparation Of Modified Coir Fibres And Its Adsorption Properties Of Noble Metal

This article uses the natural coir fibre as raw material, adopts the method of microwave pretreatment, then reacts with pyridine and PSCl3to synthesis the functional coir fibre. The characteristics of CO and Cl were determined by FT-IR, SEM, EDX techniques. The mechanism of adsorption was discussed preliminarily. Then the static adsorption of one-component and the competitive adsorption of two-component were studied, and examines the adsorption performance of functional coir fibre to Au and Ag ion. Through the study of the regeneration performance of modified coir fibre and its application in actual industrial wastewater, we draw the following conclusions:The best condition of synthetic reaction is:put coir fibre in the microwave oven, heating7min with700W power. Then take out8g and put it into the round bottom flask, add150mL of pyridine, heating1hour under90℃, then add8mL of PSCl3, heating2.5hours, after this, repeatedly wash it with distilled water and ethanol, then put it into the dryer for24h. Then weigh the coir fibre after completely dry, It is concluded that the weight of modified coir fibre increased by29.8%.Use different physical and chemical analysis methods such as FT-IR、SEM、EDX to describe the raw and modified coconut fibre. We can draw that P=S functional groups are successfully access on the coir fibre from the FT-IR figure; SEM images show that before modification, coir fibre parcel very close together and hard to contact with metal ion solution, after modification, the cell wall was destroyed, facilitate the metal ion contact the inner part of fibre; EDX tables show that after modification, P、S has been linked into the fibre, and the content of them are9.31%and8.72%respectively.The static adsorption experiment of single metal ion shows that modified fibre is6.4times than unmodified one. And the same with the first order kinetics model, the adsorption quantity will increase with the increase of temperature. And the competitive experiments shows owing to the existence of ion competition, the amount of other ions adsorption will reduce.The regeneration performance research of saturated modified fibre shows the possibility of recycle using of fibre, the adsorption rate are85%and82%to Au and Ag respectively, the recovery rate of85.9%and82.5%; and the recycling rate and recovery rate after five times regeneration are still above65%.The real industrial wastewater treatment research shows the modified coir fibre is suitable for the recycling of noble metal ions in industrial wastewater, after adsorption, the content of selenium、Au、Ag are decreased from1730mg/L、2.3mg/L、2.4mg/L to575mg/L、<0.1mg/L、1.34mg/L respectively, then Cu changed from18.7g/L to19.5g/L, Pb changed from74.1mg/L to75.7mg/L.