\documentclass[10pt,onecolumn]{IEEEtran}
\usepackage{multicol}
\usepackage{longtable}
\usepackage{balance}
\usepackage[english]{babel}
\usepackage{blindtext}

% If you want just one column, put this definition, and there is no need to edit your entire document
\def\multicols#1{}
\def\endmulticols{}
\title{Sample Title}
\author{A. U. Thor}
\begin{document}
\maketitle
\begin{abstract}
\blindtext
\end{abstract}
\begin{multicols}{2}
\blindtext

\blindtext
\end{multicols}

	\begin{longtable}{|c|c|}
		\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
		First item & Second item \\\hline
	\end{longtable}

\begin{multicols}{2}

\blindtext
\end{multicols}
\end{document}