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.