Thermodynamic study of the removal of heavy metal ions from heavy oils using tetramethyl ammonium hydroxide pentahydrate ionic liquid  

作　　者：Festus M.Adebiyi Reuben O.Yoade 

机构地区：[1]Dangote Oil Refinery Company Ltd.,1,Alfred Rewane Road,Falomo,Ikoyi,Lagos,Nigeria [2]Department of Chemistry,Obafemi Awolowo University,Ile-Ife,Nigeria

出　　处：《Petroleum Research》2022年第4期545-550,共6页石油研究（英文）

摘　　要：This study investigated efficiency of tetramethyl ammonium hydroxide pentahydrate(TMAH)in removal of heavy metal ions from heavy oils obtained from Nigerian oil sands by Soxhlet-extraction technique.Metals were removed from the heavy oils at variable temperatures using TMAH.Elemental analysis was done using Atomic absorption spectrophotometry(AAS).Percentage recovery was≥92.85%,confirming reliability of results.Total metal concentrations followed order:Ni>Pb>Mn>Cu>Cr>Cd.Analysis of variance results showed that F<F_(critical)(0.01<3.68),indicating acceptance of null hypothesis.Cluster analysis result indicated three major inter-elemental clustering groups,indicating chemical affinity and/or similar sources,while T-test result indicated significant differences.Metal removal efficiency decreased with increased temperature,indicating exothermic process.Thermodynamic parameter values were negative,confirming exothermic reactions.Also,negative△DS°values indicated decreased randomness at solid/liquid interface during the extraction.△DG°negative values indicated feasible and spontaneous extraction.Conclusively,the distribution of metals in the analyzed heavy oils followed similar trend,due to similarity in their geological activity,source rock type,maturation and depositional environment.Thermodynamics parameters values showed the extraction process was exothermic,feasible and spontaneous thus,proving metal extraction using TMAH to be efficient.

关 键 词：AAS Heavy oil Metal Thermodynamics parameters TMAH 

分 类 号：TE624[石油与天然气工程—油气加工工程]