Adsorption Onto Pecan Shell Biochar for Removal of N-Nitrosodimethylamine from Water

Sicilee Macklin

Abstract

Adsorption onto Pecan
Shell Biochar for Removal of N-Nitrosodimethylamine from Water

The constant threat of water contamination promotes development of
new methods and materials to effectively clean water before
consumption. As a known carcinogen to animals with deteriorative
effects to lungs and liver in humans, N-Nitrosodimethylamine (NDMA)
has recently gained attention in the scientific community. Harmful
consequences can result for living beings from exposure at low
concentrations of NDMA, down to the parts per trillion level.
Therefore, it is of increasing importance to remove NDMA from the
water supply.

Activated carbon
is commonly used to adsorb a myriad of compounds from water. In New
Mexico, pecan shells are found in abundance owing to the influence of
the pecan industry and are commonly thought of as a waste material.
In this project, local pecan shells are pyrolyzed, some further
activated to increase surface area, before testing their adsorptivity
of NDMA. The current focus of this project is to utilize
scintillation counting, a method used to measure the radioactivity of
materials. Carbon-14-labeled NDMA is adsorbed onto the pecan shell
char and the radioactivity of these samples determined via
scintillation counting. The measure of radioactivity then indicates
how much NDMA was adsorbed onto the pecan shell char. Various types
of char pyrolyzed at different temperatures will be compared, along
with a coconut shell carbon standard, to determine the best option
for NDMA adsorption.