The Modification Of Huining Attapulgite Clays And Their Research Of Treatment Of Nickel In Wastewater

It is very expensive and ineffective to remove metalions from wastewaters using conventional methods when the initial concentration is low (<100 mg/1). The use of adsorption is becoming research hot spot in recent years due to its low cost and convenient. Attapulgite also named as palygorskite is crystal hydrated magnesium aluminum silicate with a unique layer-chain structure which gives attapulgite's virtues of high surface area , inert chemical property and excellent adsorptive property.So it has been applied in many fields.The paper research property of the adsorption of N(iII)onto attapulgite from static and dynamic adsorption experiment. Static adsorption experiment investigate time, initial concentration, initial pH, adsorbent quantity and temperature etc. factor adsorb Ni(II)influence of the result to attapulgite clay. From the aspect of adsorptive thermodynamics and kinetics,this paper also describes adsorption behaviors of Attapulgite on Ni (II). Dynamic adsorption experiment for Ni(II)concentration, flow rate , initial pH and attapulgite bed height on the influence of penetration curve is discussed. The experimental result indicates the following:(1) The adsorption of Ni(II)onto attapulgite has been completed before 10 minutes. Adsorption rate and absorption capacity Ni(II)onto attapulgite increase rapidly as time extended . On the contrary after 10 minite they growth slowly.It indicates that adsorption already reach balance. The capacity of adsorption of Ni (II) on attapulgite increase 10.25 mg/g to32.20 mg/g as growth of initial concentration.It make known that high concentrations Ni (II) more use the ability of adsorption of attapulgite. Adsorption rate and adsorption capacity of Ni(II)onto attapulgite increase as pH rised clearly,it should be in progress under the neutral or alkaline condition. Adsorption rate and adsorption capacity of Ni(II) adsorption onto attapulgite increase as temperature improved,but the influence is not obviously. so the adsorption of N(iII)onto attapulgite in Huining could conduct at room temperature.(2)The linear correlation coefficient of Langmuir and Freundlich is R12>0.99>R22 The adsorption of Ni(II)onto attapulgite can be better to conform to Langmuir. Ni(II) adsorption onto attapulgite accords with the second order equation. It shows that the adsorption is by adsorption rate measures to control chemicals.But the the date of activation energy of adsorption obviously show that adsorption is adhering to the nature of a physical.Therefore, the adsorption of Ni(II)onto attapulgite is not only by adsorption rate measures to control chemicals or physical,but it is by adsorption rate measures to control both chemicals and physical.(3) Attapulgite bed height original N(iII)concentration, feed flow rate ,and initial pH have a great influence on breakthrough time. Under the neutral or alkaline condition,.the filler height increasing resulted in a extension of breakthrough time.while the increase of the flow rate, and the initial concentration of Ni(II)led a sharp decrease of breakthrough time. The BDST mode can fully describe the relationship between attapulgite bed high and breakthrough time,moreover, model for only change N(iII) initial concentration predicted penetration time can get satisfactory results.