Adsorption Isotherms and Kinetics Studies on Adsorption of Copper onto Modified and Unmodified Biomass Tea Waste from Wastewater in Kisii County, Kenya

Abstract

Among the most hazardous environmental issues nowadays is heavy metal pollution. One efficient technique for eliminating wastewater that contains heavy metals is adsorption. In order to assess an adsorbent's effectiveness and construct an adsorption system, the maximal adsorption capacity, the adsorption process and the movement of mass phases can all be determined in kinetics models and adsorption isotherms. This study examined tea waste treated with sulfuric acid as an inexpensive alternative adsorbent for the removal of Cu (II) ions from aqueous solution. 1M H2SO4 was added to the tea waste, and it was heated to 150°C for 24 hours.  Tea waste and tea factory wastewater was taken from Nyamache tea Factory. The adsorption kinetics and isotherms of heavy metals by both modified and unmodified biomass tea waste were compiled and thoroughly examined in this paper.  biomass quantity (0.1 to 1.0 g), pH levels (2.0 to 10.0), all had an impact on the biosorption procedure. The findings from the study show the optimum pH of the modified tea waste as 6 and for unmodified tea waste as 5.9. The optimum adsorbent dosage for modified tea waste as 0.7 grams and for the unmodified tea waste as 0.8 grams. The adsorption capacities of modified and unmodified tea waste were 14.144 and 12.706 respectively, the adsorption capacity for modified tea waste were comparatively greater than those of unmodified tea waste. For both modified and unmodified tea waste, the adsorption data fit the Langmuir isotherm model better than the Freundrich model, with correlation coefficients of 0.9477 and 0.9402, even though the adsorption kinetics matched pseudo-second-order kinetics (R=0.9999). The findings show that copper (ll) ions can be removed from household wastewater by using modified tea waste and unmodified tea waste.