a study on fe adsorption using hierarchical 3 porous activated carbon synthesized from seafood wastecrab shells and agricultural wastedurian shell

VIETNAM NATIONAL UNIVERSITY — HO CHI MINH CITY INTERNATIONAL UNIVERSITY School of Chemical and Environmental Engineering BSc THESIS PROJECT PROPOSAL A study on Fe™ adsorption using

VIETNAM NATIONAL UNIVERSITY — HO CHI MINH CITY

INTERNATIONAL UNIVERSITY School of Chemical and Environmental Engineering

BSc THESIS PROJECT PROPOSAL

A study on Fe™ adsorption using hierarchical

porous activated carbon synthesized from

seafeed-wastecrab shells and agrieutturat

wastedurian shell

Student name: Pham Gia Hung ID: BTCEIU19015

Department: Chemical Engineering Advisor: Dr Phung Thanh Khoa

02/2024

PROJECT GENERAL INFORMATION

NAME OF STUDY

A study on Fe** adsorption using hierarchical porous activated carbon synthesized from seafood waste and agricultural waste

FIELD OF STUDY

Materials Science and Adsorption ADVISOR

Dr Phung Thanh Khoa HOST INSTITUTE

International University - Vietnam National University Ho Chi Minh City TIME

From 26/2/2024 to 31/7/2024 BUDGET ESTIMATION

10 million VND

Il PROJECT CONTENTS

1 AIM

e Produce activated carbon from crab shell and durian shell activated by KOH

® Investigate the adsorption of ferric ion solution at different conditions of pH, time, and initial concentration

e Characterize activated carbon

2, BACKGROUND

2.1 Introduction

Water is a solvent and a resource for all living things in the world Due to the fact that Vietnam is on the road to industrialization This will raise the amount of heavy metal concentration presented in water due to anthropogenic activities such as mining, smelting,

foundries, and other industries that are based on metal, as well as the leaching of metals

from various sources These activities could lead to a sharp increase in the content of

heavy metal in both terrestrial and aquatic environments [1][2] Gastrointestinal issues

such as nausea and stomach pain are the most typical side symptoms of Cu” ion poisoning Anemia illness has been connected to the low Pb** levels, while major central nervous systems problems are caused by excessive Pb”" levels [1]

Besides, aqueous environment could be easily contaminated by ferric ion caused by sludge from production activity and mining or soil conditions Normally, iron- contaminated water will still have a transparent color, but after being exposed to air for a

long time, the Ferrous ion will be oxidized into Ferric iron, creating a red-brown

precipitate that causes the water to be more turbid When using iron-contaminated water for daily activities such as bathing, cooking and drinking water for a long time, it will

increase the risk of skin diseases such as allergies, dermatitis, acne, etc Yellow teeth, digestive system diseases, blood diseases, even cancer Excess iron ion in the body will

also cause weight loss, fatigue and potentially damage the liver, heart, pancreas, etc Water contaminated with iron also slows down the absorption of nutrients and digest food, thereby leading to nausea, indigestion, and loss of appetite

There are plenty of methodologies to remove heavy metal from aquatic environments such as sulfide precipitation and hydroxide precipitation, coagulation, flocculation, and adsorption However, adsorption method is an inexpensive procedure as well as

restricting chemical and biological sludge Besides, adsorption method has the potential ability to recover the adsorbent after using Activated carbon can be produced from high-

carbon resources such seafood waste, wood, and industrial waste Consequently, the

properties of activated carbon are influenced by the methods used in production and activation [3]

Durian is mainly grown mostly in tropical rainforests countries in Southeast Asia,

such as India, Indonesia, and Sri Lanka Due to the fact that durian can be harvested

many times in a year, the demand of durians consumptions in these countries, specifically Indonesia, had reached 562,710 tones per year in 1998 This will lead to the evident that durian shells will become disposed products and bring health issues such as respiratory

disease to human beings if there is no treatments [4] In durian shells, the compositions

comprised mostly are lignin (7.69%), cellulose (30.92%) and hemicellulose (17.99%) [5] Therefore, one of the most suitable precursor for producing and synthesizing activated carbon used for heavy metal ions and dyes adsorption in aqueous environments is durian

[5]

Not only agricultural waste is recycled into activated carbon, but seafood waste is also being used Millions of tons of crab shell (CS), an unwanted byproduct of processing shellfish, were produced each year [6] Large amounts of CS are currently dumped as waste in the soil environment The breakdown of these leftovers could release a variety of

chemicals or bacteria that contaminate the soil and air Therefore, a feasible and possible

solution for this is to convert that waste into high value products instead of discharging it [7] By making activated carbon, not only CS waste can be processed, but valuable products can also be generated

2.2 Literature review

2.21 Heavy metals removal There are many methods to remove metal ions in aqueous solution including physical and chemical oxidation, coagulation and adsorption [8]

Chemical precipitation: is a method to generate metal’s precipitation by using sulfide precipitation and hydroxide precipitation After that, the precipitation will be

eliminated by sedimentation [9]

+6 + HySig tF Cian &

Fe Si #2 Haq)

4

M cq)

Another method is called coagulation and flocculation Coagulants, which are composed of large aggregates of insoluble particles and/or dissolved organic components, are used in the coagulation process Poly aluminum chloride (PACL), magnesium chloride (MgCl12), aluminum hydroxide oxides, and aluminum sulfate are examples of these coagulants Aluminum sulfate (alum), magnesium chloride, and poly aluminum chloride are also utilized as coagulants [9]

There is another method called biological method which used some microbiological activity or inorganic pollutants such as hydro sulfur to clean aqueous

environment from metal ions However, using activated carbon 1s a feasible method

due to its low cost, and easy to repair [9]

Adsorption is considered as the moder, effective, and economic method to

remove heavy metal in aqueous solution The high-quality treated effluent could be depended on the design of adsorbent and operation process There are many types of

adsorbents, such as Carbon nanotube (CNT), Biosorbents, and low-cost adsorbents included activated carbon [9]

The treatment of heavy metal wastewater’s method of flocculation and coagulation produces sludge with strong settling and dewatering properties However, this approach results in greater sludge volume generation and chemical usage Using chemical precipitation in heavy metals removal has been called as traditional methods for a long time due to its basic process and inexpensive cost However, chemical precipitation process still has its drawback When treating with high concentration heavy metals, it gives highly efficient yield, and it is not efficiently effective when metal ion concentration is low Adsorption on the other hand, is recognized as the method to remove metal ions at low concentrations Although there are plenty of

commercial adsorbents such as CNT, biosorbents, and Zeolite, low cost activated

carbons are still a feasible and suitable materials to conduct low concentration metal ion adsorption because activated carbon could be synthesized from agricultural and

seafood waste [9]

2.2.2 Activated carbon synthesized from bio waste

Activated carbon is a remarkable material with diverse applications in water

treatment, desalination, wastewater treatment and air treatment due to its unique

properties To achieve activated carbon, activated agents are necessary

Activating agents for activating carbon have plenty of types One of them is an alkaline activating agent Strong alkaline activating agents such as KOH and NaOH,

the middle alkaline activating agent are K,CO;, Na,CO, and weak alkaline activating agents are Na,SiO,,K,SiO;,K,B,0,, Among these activating agents,

KOH has the most effective for preparing activated carbon, and give the highest surface area due to the fact that potassium molecules are much bigger than that of sodium [10][1 1]

The reaction is followed by:

2KOH - K,O+H,O K,O+CO, ¬ K,CO,

4 KOH +C - K,CO,+K,O+2H,ADDIN ZOTEROz CSL x„y¿y 1 citationTD :PX10dsHm,propertie: Acidic activating agents are also being used during activating steps for

activated carbon Dehydration and elimination: Under H,PO,, hetero elements like oxygen and hydrogen are eliminated as water vapor If not, they are eliminated as carbon-containing organic volatiles without H;P O,, which increases carbon element consumption and decreases carbon yield Concurrently, the process of water vapor volatilization acts as a physical activator, encouraging the creation of more pores

HPO, can also prevent tar from forming, leaving high aromatization char behind [11] Moreover, KOH also showed a higher surface area than acid activating agents [10] Because KOH provides more surface area and is safer to use than using acids activating agents, KOH is chosen for conducting thesis

2.2.3 General adsorption

The phenomenon of increasing the solute concentration at the interface of two phases which can be liquid-liquid, solid-liquid, gas-solid, gas-liquid is called adsorption

Adsorptive: molecules before being adsorbed on the surface Adsorbate: molecules adsorbed on the surface

Adsorbent: solid where adsorption takes place

There are two types of adsorptions: chemisorption and physisorption

Physisorption Chemisorption

A reversible process A non-reversible process

Adsorbate and the surface of adsorbent _| Adsorbed molecules react chemically with

6

interact only by Van da Waal the surface

The adsorbed molecules are weakly The adsorbed molecules are strongly

bonded to the surface bonded to the surface

; Heat of adsorption has the same range Heat of adsorption are low

value of chemical reaction

Formation of multilayer on the surface Formation of monolayer on the surface

The tendency of solid surfaces is to pull components from the surrounding liquid and gas phases These constituents are confined in one or more layers on the solid's surface if the constituent compositions on the solid surface are different from those in the gas or liquid phase, serve as the basis for the individual phase process The adsorbent usually has to bind reversibly to the substances it is absorbing in order

to be reused Langmuir adsorption isotherm is shown below [12]:

bxC,

ma

q.,g„: equilibrlum adsorption capacity, maximum adsorption capacity

b: Langmuir constant C,,: Concentration of adsorbent when reachingadsorption equilibrium Adsorption can be considered as a series reaction, so the stage which has the slowest rate plays a vital and decisive role in determining the speed of the reaction The adsorption capacity depends on the inward and outward diffusion and will change with time until the adsorption capacity reaches its equilibrium

ICy- CJ XV

m

With q: adsorption capacity

ing

g

V : volume of adsorbent solution| L)

m: mass of adsorbent material| g]

C,,C,:initialconcentration A concentration at equilibrium of adsorbent solution

2.3 Hypothesis

I hypothesize that activated carbon from seafood waste and agricultural waste has a

7

difference in Fe?" adsorption capacity TP Pp

3 Materials and Methods

3.1 Materials and Instruments

3.1.1 Chemicals:

No Chemical Formula

1 Iron (III) nitrate nonahydrate Fe(NO,),.9H,O

2 Potassium Hydroxide KOH

3 Methylene Blue CigH CIN ,S

3.1.2 Instruments:

No Apparatus

1 Funnel

2 Beaker, Erlenmeyer

3 Filter paper, weighing boat

4 Porcelain mortar and pestle

5 Porcelain boat

6 Volumetric flask

7 Cylinder

11 Vacuum filtration system

12 Technical balances

13 Magnetic stirrer

14 pH meter

3.2 Methods

uiverze andsieve carbonize for 2hat „ activate by KOH for

DWIAWM ———————————` ` —\ r 7 AcIaeldÐ ————— _

: ) materials ) a ) Ferric ion

materials | ——/ / powder ; _ 4 Biochar [ \ \ carbon —\/ˆ|_ adsorption

3.2.1 Preparation of biochar from durian shells and crab shells After durian shells and crab shells were collected, they are then washed to

remove dirt on both samples Then durian shells and crab shells are dry under the sun

at the ambient temperature After drying, the samples are then pulverized and sieved through 125 ym and 212 pm Powder with the particle size of 125 pm and 212 um then is put into the porcelain boat and heat in the furnace under 600°C for 2 hours to obtain Biochar Remarkably, this process needs the help of nitrogen gas flowing continuously to prevent the material are burning to ash After carbonization, the

biochar from 2 different materials is collected

3.2.2 Preparation of activated carbon using KOH

Biochar is modified to activated carbon in a furnace at 750°C for 1.5 hours by milling and mixing KOH with the ratio respect 2 After 1.5 hours, turn off the furnace

and let the activated carbon cool

After modifying biochar, 1M HC] and distilled water are used to remove KOH residual from the biochar until pH=6-7 After washing, place the materials in the oven

at 80°C for 24 hours to dry completely, then activated carbons are obtained

3.2.3 Adsorption capacity and surface area_on Methylene Blue

After obtaining activated carbon, maximum adsorption capacity on MB should

be conducted First, MB standard curve should be built up by preparing an 10 ppm

MB stock solution, then dilute it to 2,4,6,8 ppm respectively After that, 300mg/L MB

should be prepared in order to examine the activated carbon adsorption A certain mass of MB is weighted, pour into Erlenmeyer flask which contain 300mg/L MB solution, conduct magnetic stirring for 2 hours to reach its equilibrium at room

temperature Then, the residual concentration of MB should be determined by UV-Vis

at 630 nm

Derive Langmuir isotherm adsorption formula to form the straight-line equation form:

The maxim:

With

0 Ö Oo

Uo Yo O

O Oy Ua

1 ill ini lcul formula:

m(đm"

Oi

3.2.4, Fe** adsorption

Similar to MB, a standard curve of Ferric ion solution should be prepared A 1000ppm stock solution of Fe(N O,|,.9H,O are prepared by weighing 1 g of Ferric Nitrate Nonahydrate in 1000 ml volumetric flask Then dilute the stock solution into

50, 100, 200, 300, 400, and 500 mg/L by water, and build standard curve by UV-Vis

at 300nm After that, a survey on factors that affect ferric ion adsorption has been

conducted, the effect of pH, time, initial concentration_of Ferric ion should be put in

care

4 Timeline

Num Content Months

Biochar and activated

carbon synthesized

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