INVESTIGATING THE EFFECTIVENESS OF
NON PSM TREATMENT IN XRO PROCESS
DURING GROUNDWATER REMEDIATION
- AKINTUNDE OLUWATIMEHIN
OCT-11-2022

AIMS AND OBJECTIVES
• To determine release rate of percarbonate in sleeves with/without PSM during XRO.
• To determine and compare ease of deployment and recharging of sleeves with/without
PSM during XRO.
• To determine the best method for deployment of XRO products in groundwater remediation.
2

BACKGROUND STORY
Groundwater contamination is
caused by human activities
ranging from;
• Man-made products
-gasoline , oil, organic salts,
fertilizers
• Untreated wastes;
-septic tanks, underground
storage tanks, leaky landfills
3

GROUND WATER
REMEDIATION
This involve treating groundwater
by;
• removal of pollutants
• converting them into harmless
chemical.
TYPES OF REMEDIATION
• In-situ (on-site)
• Out-situ (off-site)
In-situ treatment
Image credit: https://envirosouth.com/services/soil-groundwater-
remediation/
4

EXTENDED-RELEASE OXIDATION (XRO)
Ax-Nano method of remediation involves the XRO
• Strong oxidants
-percarbonate, persulfate, permanganate
• Controlled release
- released in small parts over extended period
WHY CONTROL RELEASE
• control the release of reactive compounds
(percarbonate)
• reduce non-selective consumption of oxidants
• maintain effective treatment for longer period
5

PERCARBONATE
Properties
• Odorless with white solid appearance
• Strong oxidizing properties
• Molar mass of 156.982 g/mol
• Solubility density of 150g/l
• Molecular formula Na2CO3·1.5 H2O2
Oxidizing Properties
It reacts with water to liberate H2O2
Na2CO3●1.5H2O2 (s) → Na2CO3 (aq) + 1.5H2O2 (aq)
Percarbonate
Image source: wikipedia 6

THE EXPERIMENT
What is this experiment about?
• To test the efficiency of Non-PSM treatment in groundwater remediation
Why do this?
• Product development
• To investigate alternatives
7

STAGE GATE OVERVIEW
Stage 0: Create a Value
Proposition​
Controlled Release Percarbonate in non-
PSM
Stage 1: Define the Scope​
XRO treatment in contaminated sites on
A&T FARM
Controlled release testing or percarbonate
in the AxNano Lab
Stage 2: Complete a
Minimum Viable Test​
Supercritical Water Oxidation (SCWO)​
Stage 3: Minimum Viable
Product​
RemRx® XRO (Non-PSM)
Stage 4: Product Launch​ RemRx® Controlled release Non-PSM
8

AX-NANO Laboratory
Experiment was done by setting up a
battery reactor in the lab.
Duration of experiment was three
weeks.
The following test was done;
• Controlled release
• Oxidation-reduction potential
• PH
• Conductivity
EXPERIMENTAL SET-UP
A & T Farm
For on-field data collection, experiments was
done in the A&T farm.
Test was done on contaminated well 10, 8, 6,
and 14.
Samples were collected over 4 weeks and
tested for
• Controlled release
• Oxidation-reduction potential
• PH
• Conductivity
• Deployment test
9

MAP OF A&T FARM
10

• WM10 will have no
treatment(control well)
• WM8 will have the PSM Plus
sleeves treatment
• WM6 will have only Non-
PSM treatment
• WM14 will have three
segmented NON-PSM
treatment
11

Well Dept
(ft)
GW
level(ft
)
PVC
diamet
er(ft)
pH ORP(m
v)
Conduc
tivity(
mS/cm
)
WM10 51 14 1.75 5.9 98.1 0.24
WM8 47 14 1.75 5.7 112.7 0.22
WM6 51 14 1.75 5.9 167.7 0.25
WM14 47 14 1.75 5.7 188.8 0.68
A&T FARM SITE BOUNDARIES
Initial examination was done on
all four wells to determine
• PH
• ORP
• Conductivity
12

MATERIALS
LAB EXPERIMENT
• Potassium permanganate (KMnO4)
• Solution containing sodium percarbonate
tablet
• Percarbonate powder
• Nitric acid (HNO3)
• 100 mL volumetric flask
• Small glass vials
• Stir plate and small stir bars
• Non-woven polypropylene fabric(sleeves)
• Zipper
• Nine 200mL beakers
• Solution containing sodium percarbonate
powder
• Weighing balance
• PH, ORP, conductivity meter
FIELD EXPERIMENT
• Plastic screen mesh
• Braided rope
• Non-woven polypropylene fabric (2-4
inches in diameter)
• Water level meter
• Weighing balance
• Tape Rule
• Percarbonate powder
• 4 sample collection container (150mL)
• Sample collection tube
• PH, ORP, conductivity meter
13

METHODS
• A stock solution of KMNO4 was created by dissolving 0.03g of
KMNO4 in 30ml of distilled water to get 6mM.
• A measured 1.34g, 1.33g, and 1.34g tablet of percarbonate
was dropped into three different 200mL beakers labelled A-C
respectively. DI water was added up to the mark. This
created a solution where H2O2 was gradually released from the
percarbonate tablets.
• Sleeves were cut into smaller units of three equal parts.
A measured 0.779g, 0.797g, and 0.778g amount of
percarbonate powder were put into each sleeves and tied with
a zipper. Each tied sleeves were then dropped into three
different 200mL beaker, and DI water was added to each
beaker up to the mark and labelled D-F respectively.
• Three separate 0.80g percarbonate powder was measured
and put into three separate 200mL beaker DI water was
added up to the mark and labelled G-I respectively.
Ax-Nano Lab Experiment
14

• A stock solution of nitric acid was also prepared by
adding 12 mL of concentrated nitric acid to DI water in
the 100 mL volumetric flask
• 4 mL nitric acid solution was added to glass vial labelled
A-I
• 0.2mL hydrogen peroxide-containing solution from each
sample labelled A-F was added to the same vials and
mixed.
• Using the stir plate, a small stir bar was added into each
vials and placed on the stirring plate.
• Aliquots of KMNO4 were added in 10uL
measurements until a faint pink color was achieved(
endpoint)
• Note : For this experiment, Two drops were required to
activate the reaction.
• ORP, pH, and conductivity of each
sample were measured using the pH and ORP meter.
• Experiments were repeatedly done at different
timepoints over 3 weeks.
15

On-Field Experiment
• Three separate 14ft of non-woven
polypropylene fabric (sleeves) were measured
and cut to size.
• 2.26kg percarbonate was weighed and poured
into sleeves. Sleeves were tied with zip ties
and were mounted into 5 separate PSM. (fig A)
• The 5 separate PSM were attached
together with braided ropes, such that the total
length was 14ft. (fig A)
• 2.12kg, and 2.18kg of percarbonate were also
weighed and put into the separate sleeves
(2.12kg goes into the long un-detached sleeves
fig. B) while 2.18kg were separated into three
detached sleeves fig. C). All sleeves were
tied with zip ties.
• Braided ropes were attached to all the end of
the sleeves and loops were made for easy pull-
up during investigation.
16

• Products in fig. A were deployed into WM8
• Products in fig. B were deployed in WM6
• Products in fig. C were deployed in WM14-
ropes were tied to each sleeves with one 3
ft shorter than the next. This is to make
sure the sleeves don't get stacked to each
other.
• Samples were taken every week for 4
weeks from each well into four 150mL
container, and labelled WM10, WM8,
WM6, and WM14 respectively.
• PH , ORP, and conductivity of each sample
was analyzed in the lab using the PH-ORP
meter.
• 4mL of nitric acid were added
to 1mL sample from each 150mL container.
• Each samples were placed on the stirring
plate and KMNO4 aliquot added until
endpoint was achieved.
17

RESULTS AND DISCUSSIONS
Control release table
AX-NANO LAB RESULTS
It can be inferred from the table and graph that
sample a-f undergoes a release rate over time.
Sample g-i were completely dissolved in DI water in
the first few hours and hence, the sharp decrese in
percentage release over time.
18

ph,cond, orp table
19

A & T FARM EXPERIMENTAL DATA
Control Release Table
Sample
Weight of
Percabonate(
g)
Volume of
GW
sample taken
(ml)
Expected
concentratio
n of H2O2(M)
at full release
Concentratio
n of H2O2 at
full
release(M)
Well 8 2260 150 143.9398764 0.000158194
Well 6 2120 150 135.0232469 0.000316388
Well 14 2180 150 138.8446596 0.0001582
20

21

22
CONCLUSIONS
• Experimental results from laboratory experiment shows that percarbonate deployed in non-woven
polypropylene fabric undergoes controlled release as shown by sample d, e and f (page 18).
• Percarbonate treatment in groundwater remediation causes a positive change in pH, ORP and
conductivity as shown on page 19 and 21.
• Non-plastic screen mesh treatment has the same effect as plastic screen mesh treatment during
groundwater remediation.
• Due to invented product design (braided ropes, no canisters, and invented loops) for the A & T
experiment, samples for WM8 and WM6 were deployed easily and removed with ease for sample
collection (becomes more lighter during pull-up).
• Product design method for WM14 (page 16, fig. C) is not advisable. Ropes get tangled-up during
sample collection, and it also waste time.

23
RECOMMENDATIONS
• Additional experiment needs to be carried out to determine the volume of
groundwater present on A&T FARM (if possible). This will help to get a clear insight
on release rate.
• Samples should be collected a day after insertion to get a clear insight on how fast
percarbonate is decimated.
• Braided ropes can be subjected to lab test to further ascertain its durability.