The Study Of Treatment Of Heavy Metal Elements In Automobile Exhaust By Bentonite

The number of motor vehicles in China has rapidly increased over the past few decades.The rapid increase in the number of vehicles directly leads to a large number of vehicle exhaust emissions.Automobile exhaust is one of the main sources of air pollution today,so the research on the purification of automobile exhaust is very important for environmental protection and human health.Determination of heavy metal elements in bentonite by ICP-MS.The detection limits of each element ranged from 0.002519ng/mL to 0.3830ng/mL,and the linear correlation coefficient R~2 was 0.9993~1.000.X-ray diffraction(XRD),X-ray fluorescence spectrometer(XRF)and Fourier transform infrared spectrometer(FT-IR)were used to characterize the bentonite.It was proved that the main component of the bentonite used was montmorillonite.Bentonite was loaded on cordierite ceramic honeycomb carrier,and heavy metal elements in vehicle exhaust were adsorbed.The experimental results show that bentonite has good adsorption effect on various heavy metals in automobile exhaust.The adsorption rates of cordierite ceramic honeycomb carrier load bentonite No.8 for Cr,Mn,Co,Ni,Mo,Ag,Cd and Hg in automobile exhaust are 48.47%,82.80%,45.39%,62.34%,73.60%,70.20%,82.59%and 96.84%,respectively.Bentonite was modified with nitric acid,hydrochloric acid,and sulfuric acid.The content of heavy metal elements in bentonite original soil and different acid modified bentonite was determined by ICP-MS.The adsorption effect of various heavy metal elements in automobile exhaust by bentonite soil and acid modified bentonite was studied.The adsorption effect of bentonite after modified by sulfuric acid on Cr,Ni,Cu,Ag,Cd,Cs,Ba,Hg,Pb increased 18.38%,74.12%,12.23%,16.51%,96.30%,203.98%,14.65%,81.08%,3.373%,respectively.The adsorption effect of bentonite after modified by sulfuric acid on Cr,Cu,Ag,Cd,Ba,Hg increased6.572%,3.165%,206.4%,11.38%,10.47%,309.9%,respectively.The adsorption effect of bentonite after modified by hydrochloric acid on Cr,Ni,Cd,Cs,Hg increased 6.193%?36.75%?30.16%?13%?174.8%,respectively.