Abstract
Adsorption can be applied for solution containing low concentration of heavy metals in which helps to investigate the influence of chemical modifications and carbonization of the adsorptive capacities of sawdust foe zinc copper and nickel. This metals help to evaluate ranged between 0.130% and 0.393% while volatile matter range between 0.120% in nickel for unmodified and 0.40% in chemically modified. Results also show highest value of volatile matter (0.401%) in modified while lowest value of (0.120%) was recorded in unmodified by nickel as a catalyst. Highest value of ash content (21.05%) was observed or recorded in chemically modified samples while cowest or least in an modify samples Result of fixed carbon show general increase in carbonized than unmodified and modified. These result show that nickel, copper and zinc have good adsorption capacity for unmodified, chemically modified and carbonized form of sawdust.
CHAPTER ONE
INTRODUCTION
1.1 The industrial revolution in the past five decades have been remarkable due to an thropogenic activities resulting from increasing population, industrialization and urbanization leading to environmental pollution (Adejo efal, 2014).
A greater percentage of the pollutants that food its way into the environment are the heavy metals whose sources could be natural or anthropogenic. Natural sources includes, volcanic eruptions, forests fire, deep sea, vent and greyer, which anthropogenic sources include mining and smelting, painting and coating etc. (Abdillahi, 2013) metals exhibits health uses like the problems in the synthesis of hemoglobin effect on the kidney, gastro intestinal track, reproductive system and acute or chronic damage to the nervous system (Berman, 2016).
Agricultural waste have been recognized as cheap material for the removal of toxic metals (Azza et al, 2014). Activated carbin can be produced using two different process from a variety of carbonaceous source material.
It can be produced using ether physical or chemical activation. It is used in heater purification, food industry, oil and gas production chemical industry medicine etc. (Eyiyceme, 2018).
The adsorption capacity of agricultural by products have been shown to be dependent on various factors such as ph, temperature, adsorbent type, Adsorbentr concentration and other physiologic chemical properties (Agada, et al 2015). Heavy metals cannot be destroyed through biological degradation as in the case with most organic pollutants, therefore, it is important to enhance the adsorption capacities of agricultural wasted through modifications (Igwe, 2017). Sawdust is widely produced through sawing of woods in various locations. Most of this are discarded as waste, the use of these materials for adsorption purposes will also enhanced environmental dealiness.
STATEMENT OF PROBLEM
Metals exhibits health issues like in the problems in the synthesis of hemoglobin, effects on the kidney, gastro intestinal frack, reproductive system and acute or chromic damage to the nervous system (Berman, 2016). The heavy metals hazardous to human includes copper, zinc, etc. Such metals are found naturally in the food in trace amount which pose few problem which concentrated in a particular area however, they presents a second damage when in high concentrations (Barker 2015)
1.2 NEED FOR THE REMOVAL OF HEAVY METALS
continues discharge of industrial domestic and agricultural waste in rivers and lakes cause deposit of pollutants in sediment such pollutants includes heavy metals which endanger public health after being incorporated in food chain. Excessive amount of some heavy metals can be toxic through direct action of the metals or through their inorganic salts or via organic compound from which the metal can become easily detached or introduce into the cell (c faisal, 2013).
1.3 AIM OF THE STUDY
The aim of the project is to investigate the influence of chemical modification and carbonization of on the adsorptive capacities of sawdust obtained from different woody materials for zonic, copper and nucleic from aqueous solutions.
Conventional methods for removal of heavy metals from solution includes theme are numerous methods of exist to remove detrimental metal ions from aqueous solution they are as follows, chemical precipitation adsorption ion-exchange, electro chemical treatments reverse osmosis etc.
The use of these conventional methods however has been abandoned mostly due to certain disadvantages these inudes,
Incomplete metal ions removals.
High reagent and energy requirement
Generation of toxic sludge or other waste product.
The use of biomass for heavy metal remediation has advantage over conventional methods. These includes,
Adsorption can be applied for solutions containing low concentration of heavy metal ion.
ii) activated combine has been the most used adsorbent for adsorbing various substances.
CHAPTER TWO
2.0 LITERATURE REVIEW
2.1 BIOSORPTION
Title date, research in the area of biosorption suggests that, it is an ideal alternative for decontamination of metal containing effluents. Biosorbent are alternative since naturally occurring biomass and adsorbents or spent biomass can be effectively used.
Biosorption is defined as ability of biological materials to accumulate heavy metals from waste water through metabolically mediated (by the use of ATP) or spontaneous physico chemical path ways of uptake (not at the cost of ATP) or as property of certain types of inactive, non-living microbial biomass which bond and concentrate heavy metals from even very dilute aqueous solution(Baker, 2015).
2.1.1 ADVANTAGES OF BIOSORPTION
The following one the advantages of biosorption over conventional metal removal methods.
Cheaper production of biomass (bacteria or fungi) the cost of the biosorbent is low since they often made 4from abundant waste materials.
Use of biomass for removal of heavy metals the metal sorbing performance of different types of biomass can be more or less selective on different metals and this depends on various factors such as type of biomass, mixture in the solution, type of biomass preparation and physio chemical treatment.
Multiple heavy metals uptake at a time.
Treatment of large volume of waste water.
No need for chemical additions as highly selective for uptake and removal of specific metals.
Functional over guide range of conditions including temperature, pH, pressure of other metal ions etc.
Competitive performance: biosorption is capable of a performance comparable to the most similar techniques ion exchange treatment (horse fall eta/2012)
Reduced volume of waste or toxic materials production.
2.1.2 DISADVANTAGES OF BIOSORPTION
Saturation of active sites of metal binding higands.
Reversible sorption of metals on biomass.
2.2 CHEMICAL MODIFICATION OF ADSORBENTS
2.2.1 CARBONIZATION OF ADSORBENTS
Recently activated carbon has been used widely and its application is gruming rapidly, so activated carbon is used in water purification, food industry, oil and gas production, chemical industry, medicine etc. with the development of nuclear technologies activated carbon became as well as a major adsorbent for radio active gases and nuclear power plants waste water treatment. Resources base of activated carbon is quite vaned from crop waste to ignite coal, slightly caking for its production. The main disadvantage of activated poor mechanical strength.
Recently, this problem is particularly acute because of reducing areas of peat bogs and bioch forests. Thus, the searching for new sources of raw materials for activated carbons is of big relevance now a days. One of the technological processes of activated carbon production is the carbonation processes. This is insufficiently studied, although output of carbonized coal porous structure of activated carbon are substantially determined by the regimes of carbonization.
2.3 SAWDUST
Sawdust is a major waste produce by the wood industry. Adding value to saw dust through composition if one of the surest means by which environmental pollution could be minimized.
2.4 G.MELINA ARBOREA (family verbenaceae) is a fast growing tree frequently planted in plantations to produce wood for light construction, crafts, decorative veneers,pulp; fuel and charcoal. The species is also plante in taungya system with short-rotation crops and as a shade tree for coffee and cacao.
It is commonly called gmelina in Bang la desh, mellina g ambar in india, germelina in Indonesia, yemane in philipines and sole in Thailand, and it has many regional names (Brandis 2016, f/fRED 2016)
USES
Word: the wood is yellowish or grayish-white, even grained and very useful for planking, paneling, carriages, furniture and carpentry of all kinds (Khan and Alan 2018)
2.5 MANGO (MANGIFERA INDICA)
Mangos belong to the genus mangifera of the family Anacardiaceane. The genus mangifera contains several species that bear edible fruits, most of the fruit tress that are commonly known as mongos belong to the species mangiferaindica. The other edible mangifera species generally have lower quality fruit and are commonly referred to as wild mangos. Mango has become naturalized and adapted throughout the tropics and subtropics. Much of the spread and naturalization has occurred in conjunction with the spread of human populations and as such the mango plays an important part in the diet and cuisine of many diverse cultures.
Mango is a common garden tree through out tropics. The fruit is also eaten green, processed into pickels, pulps, jams and chutneys and is frozen or dried. The fruit is also an important source of sustenance for birds, bats insects and mammals.
MAIN USES OF MANGO
Fruits, flavoring, medicinal and timber.
Timber: mango timber when properly seasoned has been used in furniture, for carving, as well and floor panching and utensil manufacture. The timber is gray-brown often with a pink tinge. It is coarse-textured hard wood, that is easy to work and finished well. The timber breaks down rapidly if exposed to the elements with out preservation treatment.
2.6 HEAVY METALS
Heavy metals include metals such as lead, cadmium chromium, Arsenic, mercury, iron, zinc, copper, Nickel etc. and metal compounds that negatively affect peoples health. Heavy metal is usually defined as metals having density more than 5g/cm3. They are classified as essential and non essential metals. The metals which are needed for normal cellular growth are essential metals e.g Zinc, Nickel, Copper etc. such metals are required in low concentrations (nm) but at higher concentrations to all heavy metals have detrimental effects to organisms if the metals have no known biological function, they are non-ess entail (sabashamum etal 2018) e.g lead, cadmium, mercury, such metals are toxic at any concentration.
2.6.1 NICKEL (N1)
Chemical element, ferromagnetic metal of group 10 of the periodic table markedly resistant to oxidation and corrosion. Nickel has atomic number of 28 atomic weight of 58.69, boiling point 2, 732oc, melting point of 1,453oc and oxidation stated, o,+1+2,+3.
PROPERTIES, OCCURRENCE AND USES
Silvery white, tough and harder than iron, nickel is widely familiar because of its use in coinage but is more important either a s the pure chemical elements.