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Undergraduate Chemistry Full Dissertation Sample

Published by at December 12th, 2022 , Revised On January 18, 2024

Reduction of Ozone Depleting Emissions in Rocket Fuel


Rocket launches can impact the atmosphere in manners that are immediate, episodic, and even long-term. Research shows that the stratosphere is immediately affected after the launch of a rocket vehicle.

The impact spreads on the trajectory of the vehicle along its flight path. It is evident that emissions from certain types of launch vehicles like solid rocket motors (SRM) significantly agitate the atmosphere along the launch trajectory.

The current report details how ozone concentration is temporarily reduced by producing an aerosol plume and its consequent
combustion products, including chlorinated compounds, alumina, NOx, and other reactive radicals.

The report shows that there is great potential for rocket fuel to impact the global and local stratospheric ozone due to chlorine increase. The report focuses on current research that has contributed to the literature on ozone depletion from rocket fuel.

The report also presents a proposal to further investigate depletion based on the introduction of alternative rocket fuel.

Background and History

The fascination for space exploration by man has been ongoing since the 1940s, with German scientists testing the V-2 rocket successfully in 1942.

Since then, both the then Soviet Union (current-day Russia) and the United States of America have conducted space programs beginning in the late 1950s using various launch vehicles. In itself, rocket launches used for space exploration are gaining in popularity due to advancements in technology.

A greater number of rocket launches are being demanded space exploration, national security, reduction in launch costs, and the emergence of private markets for tourism, solar energy, and manufacturing. Historically, strategic missiles had used various liquid-propellant engines, starting with the German V-2 rocket.

However, there was an increased need for instant readiness of strategic missiles required for a different type of fuel to be used, eventually leading to various solid fuels.

Rocket launches affect the natural environment, specifically their impact on changing the composition of the atmosphere during its flight path. According to Ross, Toohey, Rawlins, Richard, Kelly,…Sheldon (2000), about forty percent of the total ozone present is destroyed from rocket plumes.

Early research conducted by Potter (1977), Potter (1978), Prather (1990), and Bennett and Hinshaw (1992) conclude that solid-fuel rocket motors used in large space launch vehicles release gases and particles that may considerably impact the stratospheric ozone densities that are along with the play of the vehicle.

Both liquid and solid rocket fuels deplete the ozone in different ways. The ozone depletion method in the stratosphere by solid rocket exhaust products is caused by it containing large amounts of chlorine substances.

Effects of Solid Rocket Fuel

According to Ross, Danilin, Weisentein, and Ko (2004), solid rocket motors are responsible for about one-third of the stratosphere fuels in the atmosphere from rockets, while liquid propellants account for two-thirds. Terry, Sippel, Pfeil, Gunduz, and Son (2016) reported that solid rocket fuel is made up of aluminum, ammonium perchlorate, and a polymer matrix.

The combustion of this solid fuel results in the chlorine in the exhaust that is derived from ammonium perchlorate. The main volatile compound created from the combustion of solid rocket motor from its plumes is hydrochloric acid (HCl).

The major presence of chlorine in rocket plumes is attributed to HCl, which is derived from afterburning, which allows for the conversion of HCl to pure chlorine molecules. Ross et al. (2004) describe afterburning as an occurrence from rocket engines burning propellants with an excess of fuel compared to the oxidizer.

The previous research notes that conversion between the two takes place from the high concentration of oxygen (O) and hydrogen (H) molecules (M. N. Ross et al., 2004). Outlined in the research is a possible reaction for the conversion:

𝑂𝐻−+ 𝐻𝐶𝑙(𝑔)→𝐻2𝑂(𝑙)+𝐶𝑙−

Equation 1-1: Conversion Reaction in Afterburning (Source: Ross et al., 2004)

Research conducted by Bloss, Nickolaisen, Salawitch, Friedl, and Sander (2001) found that the catalytic ozone destruction cycle involves ClO self-reaction that is considered the dominant gas-phase ozone layer destruction process that mostly takes place in the stratosphere. Bloss et al. (2001) outline the following mechanism as the main cause of ozone destruction:

𝐶𝑙𝑂+𝐶𝑙𝑂+𝑀 → 𝐶𝑙2𝑂2+𝑀       (1)
𝐶𝑙2𝑂2+ℎ𝑣 →𝐶𝑙𝑂𝑂+𝐶𝑙             (2)
𝐶𝑙𝑂𝑂+𝑀 →𝐶𝑙+𝑂2+𝑀              (3)
2 ×𝐶𝑙+ 𝑂3→𝐶𝑙𝑂+ 𝑂2              (4)


Equation 1-2: Gas-Phase Ozone Destruction Process (Bloss et al. 2001)

This and other chlorine mechanisms show that Cl2 combines with ozone once exposed to light from the hypochlorite (ClO) molecule and diatomic oxygen (O2). Resulting in the impact of oxygen available to inhale.

Then a ClO combines with another ClO in the presence of a third body (M) described by Bloss et al. (2001) as a solid surface that allows the entire reaction to occur. Lohn, Wong, Spencer, Meads, and Molina (1996) found that the reason this entire reaction is so harmful to the ozone is that chlorine can recycle and destroy another ozone molecule over and over again in a continuous cycle.

Researchers have found that on average, over five to ten molecules in the ozone are expended by every chlorine atom that is deposited from the rocket fuel (Bloss et al., 2001; Lohn et al., 1996; Martin Ross, Darin Toohey, Manfred Peinemann, & Patrick Ross, 2009; M. Ross et al., 1997; Toohey, 2003).

Ross et al. (1997) found that chlorine is confirmed to be the greatest contributor to ozone loss from rocket fuels based on the data collected from rocket launches. This results from the need for sunlight to activate the Cl to begin the destruction of the ozone cycle by these molecules.

Effects of Liquid Rocket Fuel

Aside from solid rocket fuels, liquid rocket fuels are also used in rocket launches. Liquid rocket fuel is considered to be better in use as the rocket thrust can be adjusted while in mid-flight compared to solid rocket fuel that burns at a fixed rate without any way to alter it.

Many in the scientific community believe that combustion from liquid rocket fuel causes some destruction of the ozone by its nitrogen mechanism.

Ross et al. (2004) expressed that nitric oxide (NO) is a known mechanism that allows the destruction of the ozone and is once present from the combustion of liquid rocket fuels, which has mostly been eliminated. Later, Ross and Sheaffer (2014) reported that the NO mechanism is not as ozone-depleting as solid rocket fuel.

The destruction of the ozone was short and only occurred immediately after launch, reducing the time for ozone destruction. The NO mechanism is known to have a slower catalytic cycle than compared to ClO mechanism leading many to conclude that liquid rocket engines are less harmful to the stratospheric ozone than their solid counterparts (Ross M. N. et al., 2000; M. N. Ross et al., 2004; Terry et al., 2016).

The Modern Paradigm

Currently, rockets have a negligible impact on the destruction of the ozone layer on a global scale compared to other causes. However, there is renewed interest on a global scale for rocket launches, which may have a larger impact on the ozone in the future.

Therefore, it becomes imperative to consider changes in fuel sources to decrease the effects of rocket fuel. Lohn et al. (1996) noted that advancements had been made to make liquid nitrogen fuel non-nitrogen-based to decrease NO’s impact on ozone loss. Zittel (1994) suggested using chlorine-free rocket fuel to eliminate the impact of chlorine radicals on destroying the ozone.

Limited research is available to predict the extent of this destruction, but studies have been conducted to understand its significance with limited data. Smith, Edwards, and Pilson (1999) argued rocket launches have the potential to impact the atmosphere in an episodic manner (immediate impact) and a cumulative manner (long-term impact).

One of the immediate effects found on the stratosphere is after launching with the destruction of the ozone caused along or near the vehicle’s flight trajectory. Certain types of launch vehicles are seen to significantly disturb the atmosphere along the trajectory with an estimated range of 10km or less from the vehicle’s passage (Smith et al., 1999).

During this time, the ozone concentration is momentarily reduced, allowing for aerosol plumes to be produced along with combustion products like chlorinated compound, alumina, NOx, and reactive radicals; these are known to change the actual chemistry along the path trajectory (Smith et al., 1999).

There is also a known local effect on the stratosphere by rocket launches that extensively reduce the ozone for up to two hours through the expanding exhaust plumes after the rocket’s launch (Smith et al., 1999).

Within the expanding rocket plume, an ozone hole is formed and increases in size two hours after launch. However, researchers have found that the ozone concentrations recover to their original levels pre-launch as time passes with the ozone back-filling into the Hole through diffusive processes during this time.

This phenomenon depends on factors like the quantity of released and the size of the launch vehicle. It has been recorded, though, that the time for the Hole to refill to its normal ozone levels was 3000 seconds at 15-20km and 6000 seconds at 40km. These numerical are based on the measurements concluded by Ross et al. (1997) and the modelling found in studies of Lohn et al. (1999).

For some time now, researchers believed that a relatively inactive form of Cl, hydrogen chloride (HCl), was the only solid rocket motor (SRM) chlorine emissions species.

Further research into the radicals with more weighted calculations and laboratory experiments such as () have concluded that chlorine is also as Cl2 or Cl radicals. It may be considered minor for some.

Still, it is significant in that while HCl mainly adds to the worldwide chlorine burden causing global ozone depletion, the extremely active forms of chlorine participate in the destruction of ozone at an immediate and local level. Researchers have developed model simulations of excessive ozone losses within the first few hours of a rocket launch, documented through the launch data of vehicles like Space Shuttle, Titan III, and Titan IV (Lohn et al., 1996; M. Ross et al., 1997).

Moreover, to the effects mentioned earlier on local ozone, the emissions from rockets are thought to have long-term and global effects on the stratospheric ozone. Many researchers believe that the potential long-term and global ramifications are attributed to the long lifespans characteristic of alumina particulate and HCl in the stratosphere.

Ko (1999) does argue that rocket motor emissions only represent a small fraction of the entire manmade impact on the chemistry of the stratosphere. Studies like Jackman et al. (1998) had carried out detailed modelling calculations of ozone depletion in the stratosphere using the launch rate of nine ‘Space Shuttle’ launches.

While Molina (1999) tested three from the Titan IV launches annually through the use of reaction probability measurements of ClONO2 with HCl on alumina surfaces. Both studies’ results indicate that the annual global average of total ozone’s impact decreased by 0.025% in 1997.

Based on these results, one-third of the decrease came about from solid rocket motor emitted alumina while the remaining portion resulted from solid rock motor emitted HCl. The results produced by Jackman et al. (1998) and Molina (1999) were substantiated independently from the research of Lohn et al. (1999) and Ko et al. (1999).

Smith et al. (1999) find that some of the potential long-term effects from using solid rocket motors include a worldwide reduction in the stratospheric ozone, increasing Cl load in the stratosphere, and an increase in the specific particulate burden.

Based on the modelling presented by Jackman et al. (1998), Ko et al. (1999), Lohn et al. (1999), and Molina (1999), it is evident that there are global ramifications from SRM fuels, but they are minor but existent and long-term.

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Major Issues Explored

A majority of studies examining the impact of rocket fuel on the ozone often use either in-situ measurements or laboratory studies to conduct their research. Research conducted by Ross et al. (1997) is an example of an in-situ study.

A majority of in-situ measurements suggest that solid rocket motor launches create ozone loss immediately after launch. When comparing the available in–situ data to that of modelling attempts, it is evident that models produce results that show a slight underestimation of the area’s size and duration in which ozone is removed by both large and medium launch vehicles.

Even though such a loss occurs, the ozone reduction only exists over a few kilometres of area and was later on found to be much smaller than expected. The local ozone reductions had decreased to a value near zero over the course of a few days, in which the effects to the concerned region also reduced and became smaller than a TOMS satellite can detect and log.

Laboratory studies conducted by Disselkemp (1999) focused on the uptake and deposition of NO and NO2 on the surface of Al2O3, due to the adverse effects of both compounds on the environment, out of which, one effect is increased catalytic destruction of the ozone by halogen species and derivatives.

Consider that the nitrogenous oxides’ concentration is 10 parts per billion volume then 640 particles/cm3 (2.5 x 10 10 molecules/ cm3) of Al2O3 is required to remove all particles of the nitrogenous oxide. However, the volume of aluminium oxide in the exhaust gases is far too low to cause a significant amount of damage to the ozone compared to the damaging effects of halogen species, specifically chlorine gas.

Another ramification of this type of chemical activity was to consider the uptake of halogens on aluminium oxide’s surface. Here, Disselkemp (1999) proposed that the absorbing of halogens by the aluminium oxide particles to evolve nitrogen oxides can increase the ozone concentration.

It can be done as the concentration of halogen species is greatly reduced and hence, a decrease in the catalytic destruction of the ozone is also observed, however, no additional data is available to support this idea. As a result, further study is required to understand and characterize halogen species’ chemistry.

Molina (1999) added to the plethora of research using laboratory studies by analysing the reaction probability (γ) of ClONO2 with HCl on an alumina surface. Molina (1999) concluded that the probability of the two’s reaction was a value that was γ=0.02 under conditions similar to that of the lower stratosphere.

This reaction was categorized as a near-zero reaction in HCl due to the dependency of the reaction on absorbed water layers and not on the nature of the refracting oxide surface itself. Detailed studies showed that a noteworthy fraction of the injected alumina surface area is catalytically active and remains un-affected in the stratosphere by sulfuric acid vapours.

It took about eight months for the alumina surface sample to get covered by sulfuric acid in a single layer with an accommodation coefficient of 0.1. Finally, coalescence with sulfuric acid vapours in the stratosphere is insignificant for alumina particles with a diameter larger than 1μm before being removed from the stratosphere.

For alumina particle distributions less the 0.13μm, the mass-weighted atmospheric lifetime is approximately 0.3 years as such particles’ reactivity is extremely small, regardless of sedimentation and collision removal status. Ko et al. (1999) replicated and produced the same results from their research’s 3-D model.

Critical Analysis

Methodologies used in analyzing ozone depletion impact further research needs and policies to minimize stratospheric ozone depletion from rocket launches. As discussed in the previous section, depletion of local stratosphere ozone within the launch vehicle’s plume is measured using in-situ measurements and other field techniques that can only be used in a small window of opportunity.

When examining the phenomenon on a worldwide scale, depletion of the ozone from rockets is calculated primarily through theoretical models. However, these models are known to produce detection limits below what current measurement techniques have confirmed.

With the available data it is concluded that if the frequency of rocket launches using solid rocket motors/propellants increase from a global increase in government and private rocket launches, there will be a significant increase to the extent of the depletion of the ozone.

Due to the potential implications of using SRM rockets, it has become imperative to introduce and experiment with limiting pollution from substances like HCl in rocket launches to significantly minimize or eliminate launch site contamination leading to ozone depletion.

There are many published literature available that analyzes and discusses the impact made on the ozone through ozone reactive compounds seeped into the stratosphere by SRMs such as studies conducted by Brady et al. (1994), Denison et al. (1994), Jackman et al. (1998) Ko et al. (1999), Prather et al. (1994), Ross et al. (1998), Takenaka and Yamagokoro (2004), Terry et al. (2016), Voigt et al. (2013), Zittel et al. (1994).

Based on these studies’ results, Cl and oxides of Cl are present within the exhaust of SRM. These studies also concur that there are two other classes of compounds generally present in exhaust from a rocket known to cause ozone destruction – nitrogen oxides and hydrogen oxides.

Both of these are generally present in the exhaust of every launch vehicle regardless of its size. Takenaka and Yamagokoro (2004) also found that species of alumina and soot from the kerosene fuel in rocket exhaust enable heterogeneous reactions between chlorine compounds and ozone.

To do so, it is common for experiments that computer models of implications of rocket exhaust on the atmosphere are conducted and then validated through laboratory experiments. A majority of the data in terms of chemical (chlorine and alumina) deposits into the stratosphere are provided through the research of Bauer and Zondervan associated with The Aerospace Corporation (as cited in Brady et al., 1994).

The method used for this was the total mass of exhaust being calculated through the corporation’s simulation code. Then the amount of chlorine and alumina are calculated from their known percentages from the exhaust. The data is presented in tons as illustrated below.

Table 4-1: Chlorine present in Stratosphere, tons/launch (Source; Smith et al., 1999)

Altitudes (km) Total Amount in Stratosphere
Vehicle 15-25 25-45 45-60
Ariane 5 57
Shuttle 40 39 0 79
Titan         IV


23 30 2 55
Titan IV 20 27 2 48
H2 3 7 1 11
Delta II 2 5 1 8
MX 2 3 1 6
Atlas IIAS 2 2 0 3
H1 1 2 0 3
MMIII 1 1 0 2

The particles of alumina and chlorine can destroy the ozone directly as corroborated by the results in Brady et al. (1997) as these particles also contain iron and chlorine from the exhaust which is known to be more reactive.

It is evident from the data accumulated in tables 2-1 and 2-2 that individual space launches release a small portion of the total potential ozone reactive species loading in the stratosphere.

Nonetheless, the accumulative effect of the rocket launches globally mare be even more significant as asserted by Lohn et al. (1999), Takenaka and Yamagokoro (2004) and later Voigt et al. (2013).

When analyzing the various literature available, the study of Molina et al. (1999) stands out as it conducted laboratory experiments on chemical processes involving the effects of particles emitted from SRMs into the stratospheric ozone.

The study emphasizes the proficiency of the catalytic chlorine activation process known to take place on the Al2O3 particle surface. The proposed reaction from previous work in Molina et al. (1996) presented the catalyzed reaction using α–alumina surfaces.

𝐶𝑙𝑂𝑁𝑂2+𝐻𝐶𝑙 → 𝐶𝑙2 + 𝐻𝑁𝑂3(𝑙)

Equation 4-1: Catalytic Chlorine Activation Process (Molina et al., 1999)

According to Smith et al. (1999) the reaction represents the most important process that results in the transformation of reserved Cl species to free Cl atoms in the stratosphere. Studies such as Ko et al. (1999) has shown that these atoms efficiently deplete the ozone through its catalytic cycles.

Based on the laboratory experiments Molina (1999) conducted, the hypothesis was that water was absorbed on the surface of the alumina particles, allowing the reaction of activation Cl as it was made available a portion of high-affinity hydrochloric acid molecules.

The study infers that solid rocket motors emitted alumina particles that were catalytically active in the stratosphere as they were covered in absorbed water. The experiments also found that the particles recovered their surface OH groups by reacting with water vapour in the form of OH and HO2 radicals.

Building on the research it was essential to understand the immediate effect of exhaust plumes in the atmosphere. However, Smith et al. (1999) reports that there is a complete lack of data on the makeup of exhaust plumes during the first several hours immediately after launch, making it difficult to develop models on the depletion of the ozone.

Eventually, the first ozone measurement on solid rocket motors plume was reported by Pergamet et al. (1997). According to Pergamet et al. (1997), a 40 per cent reduction during a single plume passed the altitude of 18 km.

The study did suggest that it observed a loss caused by the presence of an ozone destructive exhaust component. Unfortunately, the measurement of uncertain reliability was not repeated in the in-situ investigations. It was left unclear if the predictions of substantial ozone loss in solid rocket motors plume were valid.

McDonald et al. (1995) built on the works of Molina (1999) and Pergamet et al. (1997) to show the impact of ozone destruction due to the various principle classes of ozone destroyers. Based on the data illustrated in the table below, the portion of the ramifications identified associated with rocket launches was less than 0.034 per cent.

Table 4-3- Chemical Compounds in exhaust causing ozone Destruction (McDonald, 19991)

Contribution to Ozone CW (Ozone

destruction to ozone.

Attributable     to     all
Nitrogen Oxides 32 0.0005
Hydrogen/Hydroxyl 26 0.0012
Oxygen 23 <0.00005
Chlorine 19 0.032

The data also illustrates that Cl has the most impact from rocket emission worldwide using McDonald et al. (1995) outcomes. Vehicles like the Zenit-3SL are known not to release Cl and its compounds, and therefore it was concluded by FEAFSLP (1999) that the Sea Launch Programme would not have a significant impact on the worldwide ozone.

It should be noted that the in-situ methods from McDonald et al. (1995) were replicated by Tishin et al (1995) to analyze Russian made rocket vehicles which also led to the same conclusion presented by McDonald et al. (1995).

Other studies like Brady and Martin (1995) and Brady et al. (1997) had estimated the potential ozone hole in terms of size and duration from the launching of vehicles V 551/552 and Delta Iv M+. In-situ for these studies including Brady et al. (1994) was to compare the local stratosphere impacts from vehicle launch. Their data is illustrated in the table below.

Table 4-4: Comparison of Lift Vehicles with Solid Rocket Motors (Brady et al., 1994; Brady and Martin 1995, Brady et al., 1997)

Vehicle Cl     Release      Rate


Diameter    or    Hole


Duration    of    Hole


Space Shuttle 4.3 5 97
Titan IV 2.0 4 25
Atlas V 551/552 0.65 2 3.6
Delta IV M+ 0.36 3 1.3
Delta        IV        M+


0.42 2 1.0
Atlas II AS 0.10 0.8 0.1
Delta II 0.30 1 0.9

Based on each of these studies’ values, the lift vehicle that is considered proposed needs to have an estimated ozone hole that lasts for just a few minutes and has a limited size in terms of its ozone hole. In all three studies, it is concluded that Space Shuttle has the most Cl release rate compared to other launch vehicles and has a greater hole diameter and distance.


Many previous studies into the improvement of rocket fuel have looked at ways to eliminate Cl, HCL, AL2O3, and CO2 production. By proposing alternative fuels, ozone depletion is greater if reduced to a significant or completely.

But there is also a chance that the same effects can come about, but through bio-mass to make bio-fuel for rockets. Researchers at Georgie Institute of Technology and Joint BioEnergy Institute were able to genetically engineer a specific version of E. Coli capable of producing pinene (Sarria, Wong, Martín, Keasling, & Peralta-Yahya, 2014). Keeping to this theme of bio-mass the following is proposed.


Biomass is a comparatively inexpensive material even to plastic as it is derived from living or decomposed organisms. Biomass can be converted into biofuel which is achieved through various methods.

Historically speaking, humans have cultivated and harnessed biomass energy since Neanderthals discovered wood can make fire. Today’s economy demands a clean, original, sustainable, and renewable resource that minimizes damage to health and the surrounding ecosystem.

Thus, many countries are shifting to a more renewable energy-based economy as it has potential for long term sustainable fuel that can meet the demands of a growing economy without depleting natural resources.

Hydrocarbons are advantageous since they can be used as fuels, lubricants, and solvents without the impact of environmental risks such as ozone depletion, air pollution, and global warming.

The purpose is the production of hydrocarbons which can be further exploited depending on needs. Catalytic depolymerization of plastics and biomass is a method that has been widely used for extracting hydrocarbons which can be used as industrial feedstock. Currently, wastes are being used to produce many other resources, such as renewable and clean fuel.

Extracting hydrocarbons from waste products is beneficial economically as it is cheaper to find the startup material to begin the process. Furthermore, from the extraction process, there will be an accumulation of smaller molecules that can be used to produce new petrochemical and furthermore plastics.

Thermal Depolymerization (TDP) using catalytic-fast pyrolysis is used to reduce complex organic materials, specifically for this study; plastics and biomass. The process is known to produce products such as aromatic compounds and hydrocarbons.

The energy from the pressure and heat of the process decomposes long chains of hydrogen, oxygen and carbon into shorter chains of hydrocarbons currently known to have a maximum length of an estimated eighteen carbons. Therefore, there is great potential to further the extraction process to produce petrochemicals

Current Literature

Catalytic Pyrolysis is known to be an emerging technology for converting biomass like lignocellulosic into liquid products such as benzene, xylene, and toluene which are known to be imperative feedstock for various industries as well as high octane liquid fuel.

The specific process of catalytic fast pyrolysis involves using fast heating biomass feedstock in the presence of a zeolite catalyst in a temperature between 400°C to 700°C. This process has been extensively used to produce aromatic from glucose through the process of catalytic fast pyrolysis (Li et al., 2013).

Since Catalytic pyrolysis is a developing technology being used to study biomass conversion technologies to hydrocarbon fuels. It is essential to incorporate the barriers and target research toward reducing the conversion costs of using such a technology.

Many studies have analyzed process designs and preliminary economic estimates for the several pathways found in the process reaction.

Upon further analysis from a study (Biddy et al., 2013), woody biomass using ex-situ catalytic fast pyrolysis was upgraded to using hydrocarbon blendstocks of gasoline-, diesel-, and jet- range hydrocarbons. Taken into consideration is a process block that may be used to research as it has been beneficial to many researchers before.

heat generated

Figure 5-1: Process Block Diagram (Source, Biddy et al., 2013)

This process diagram is an outline that can be improved in terms of the development of catalysts with improved yields, stability, lifetimes, maximizing overall conversion to the desired hydrocarbon product, and developing biofuels that can contribute to the current economy. The model is based on the circulating fluidized bed that consists of a pyrolysis reactor, cyclones, and combustor (Biddy et al., 2013).

There are various advantages of using catalytic fast pyrolysis to convert biomass to gasoline range aromatics as it can directly convert solid biomass into liquid fuel. Other routes of that are known to convert solid biomass to liquid fuel in multiple steps at longer residence times, resulting in the drastic increase of cost of biomass processing (Carlson, 2010).

Proposed Study

To produce the end products of biofuel, Catalytic Pyrolysis will be used on biomass, plastics, and then in combination (biomass + plastics). Initial testing will be performed followed by investigations which are as follows:
1) Analyse the operation of Catalytic Pyrolysis using various techniques.
2) Identify a biomass
3) Identify a plastic
4) Identify catalyst being used
5) Then process beings with catalytic pyrolysis of chosen biomass, then plastic, and a combination of plastics + biomass
6) Identification of products from each of the pyrolysis
7) Observe the feasibility and success of the process
8) Identify issues, problems in experimentation and areas in which improvement can be made.
9) Identification of parameters:

i. Conversion efficiency of biomass into products
ii. Affect on & Activity of catalyst
iii. Production Yield
iv. Formation & Yield of coke in process

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Recourse Summary

Contribution to Ozone CW (Ozone

destruction to ozone.

Attributable to all
Nitrogen Oxides 32 0.0005
Hydrogen/Hydroxyl 26 0.0012
Oxygen 23 <0.00005
Chlorine 19 0.032

Impact Statement

Impact Summary

The research on improving rocket fuel for limiting its adverse impact on the ozone large is a potential issue that affects people from academia to corporations to private citizens worldwide. By further researching the issue with better technology and vigour the research will first and foremost benefit the space launch industry in both the private and public sectors.

Public sector space launch organizations are already examining the adverse impacts that launch emissions have on the ozone stratosphere. Further research into the field as proposed will allow for applicable solutions, especially for solid rocket motors, limiting its ability to emit Cl and other harmful substances from its launches.

The entire research is based on ensuring that the academic findings are available for public sector launches to cut costs of governments funding space programmes.

The private sector is also another imperative sector that needs to be targeted for the proposed research. Recent endeavours by private companies, especially that of Space X, are essential for-profit companies to understand the environmental ramifications of launches.

Therefore, the aim of the proposed research makes it necessary to provide the research to private companies for consideration. Both the public and private sectors need to regulate rocket vehicle launches to ensure that there are no adverse effects on the environment.

Academic Beneficiaries

The proposed research is also of benefit to other academics researching or looking to research the impact of rocket fuels on ozone depletion. The subject is of great interest especially due to the known effects of climate change and immediate effects seen significant holes were developed in the ozone due to anthropogenic activities.

Academics understand that it is highly likely that rocket launches in the future will be a potential danger to the ozone from the increasing interest by private and public sectors.

This is imperative for the academic community to propose solutions before the frequency of rocket launches exceed. Hence, the proposed research is a stepping stone for understanding the impact of rocket fuel on ozone depletion.


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Frequently Asked Questions

Solid Rocket Fuel has minimal direct impact on the ozone layer since it doesn’t contain chlorine or bromine, which are the primary ozone-depleting substances.

Liquid rocket fuel does not directly damage the ozone layer. However, certain byproducts from its combustion, such as nitrogen oxides, can contribute to ozone depletion when released into the upper atmosphere.

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