Extraction Characterization and Dye Adsorption Ability of Chitin From Crab Shell Watste - Free Essay Example

Sample details Pages: 5 Words: 1594 Downloads: 2 Date added: 2019/03/18 Category Analytics Essay Level High school Tags: Characterization Essay Did you like this example? ABSTRACT Chitin is the second most abundant natural polysaccharide after cellulose and is present in the crustacean exoskeleton like crab, shrimp, insects and fungi. It is the main structural component of the exoskeletons of the animals like insects and crustaceans. Crab, shrimp, squilla and fish scale waste is ideal raw material for chitin production. Don’t waste time! Our writers will create an original "Extraction Characterization and Dye Adsorption Ability of Chitin From Crab Shell Watste" essay for you Create order The present work is aimed at extraction of chitin from crab shells. The methodology include acid hydrolysis, demineralization followed by deproteinization step. The chitin produced is analysed by FTIR based on the interpretation of the spectrogram of the two samples of chitin synthesized in the present work, it can be said that all functional groups expected are seen. The applications of the chitin are numerous but the study is focused on dye adsorption ability. INTRODUCTION The shell fish industry which is prominent in all costal countries generates about 60,000 to 80,000 tons of waste (Muzzarelli et al,1986). Even though the wastes are biodegradable, the dumping off large quantities makes degradation process slow resulting in accumulation of waste overtime which is a major environmental concern. A quick and effective solution to this is recycling of shell wastes and extraction of commercially viable substances like chitin from them. Chitin on its own has various applications. Chtin is a natural polysaccharide of major importance. This biopolymer is synthesized by enormous number of living organisms and it belongs to the most abundant natural polymers, after cellulose (Rinaudo et al,2006). Expelling of dyestuff into water resource system causes major threat to the environment. Adsorption is the cost effective and potential method to remove the dyes from the effluents. Effluents from various industries contain harmful coloring agents, which have to be removed to maintain the quality of the environment. Paper, fabric, leather and dyestuff production are some of the industries that release harmful effluents (Lin S, Lin Cet al,1993).The aim of the present study was to investigate the chitin adsorption capability on major industrial dye, Methylene Blue. MATERIALS AND METHOD Sample preparation- Crabs were collected from Dapodi fish market, Pune. Crabs inedible parts including head, body shells and tails were removed from the whole body for extraction of chitin. The crab shell were washed and air dried and used for extraction. Extraction of chitin- Crab shell waste Crab shell powder Demineralization Deproteination Extracted Chitin Figure 1.Flow chart of basic steps of Extraction of Chitin. Process I- 10 grams of sun dried crab shell waste was demineralized by adding 1.5 N HCl at room temperature for 1 hour. Acid was discarded and the shells were washed with distilled water until the pH is neutral. The shells were then de-proteinized with 0.5% NaOH at 100 °C for 30 minutes. Protein solution was removed and washed thoroughly with distilled water and the pH was checked. The de-proteinization process was again repeated, for that 3% NaOH was added to the sample at 100 °C for 30 minutes. After draining the residual proteins along with the effluents, the sample once again washed and the pH was observed till it was approximately near to neutral. Hence the chitin slurry was obtained. The excess water was removed. The alkali was drained off and washed thoroughly with distilled water until the pH is less than 7.5 and then dried at ambient temperature (30 ? ± 2? °C) Process II- 10 grams of crab shell waste were refluxed in 100ml of sodium hypochlorite (NaCLO)solution at 100oc for 10 minutes. The NaCLO solution was decanted and the powder was washed with distilled water. The above step was repeated once more. The sample was again refluxed in 50ml of 1M HCL at 75oC for 15 minutes. The solution was decanted and washed with distilled till it becomes neutral. The sample was then refluxed in 50ml of 1M NaoH(sodium hydroxide)solution at 100oC for 2 minutes to remove any protein residues. The solution was decanted and remaining sample was washed with distilled water till it becomes neutral. They were filtered off and placed in an oven at 60oC for a week. Characterization of Chitin Solubility Test Chitin dissolves completely in 1% Acetic Acid. For the estimation of chitin produced the sample was taken out of the storage and weighed . Then the sample was put inside a clean beaker and 10 to 20 ml of 1% acetic acid was added to it. The solution was kept in shaker for 30 to 40 minutes. Then the sample was taken out and weighed, carefully( Abhrajyoti Tarafdar et al,2013) FT-IR Spectroscopy: The samples were analysed by FT-IR spectroscopy in Istrumentation Centre Solapur university and the graph depicts wave number versus percent transmission. (Pandharipande S et al,2016) Dye adsorption by Chitin:Stock solution of the dye was prepared by taking 10mg of methylene blue powder and adding it to 1000ml of distilled water( Paula Szymczyk et al,2015).The pH of the dye solutions was adjusted using 1 N NaOH or 1 HCl.About 1g of extracted Chitin(adsorbent) was added to 100mL of dye solutions(adsorbate). A control was also maintained without addition of chitin. At specific time intervals, aliquots of 2-3 ml suspension were filtered and used to evaluate the adsorption of dye.The absorbance spectrum of the supernatant was subsequently measured using UV-Vis spectrophotometer. Concentration of dye adsorption was calculated by the absorbance value at 668nm. Percentage of dye adsorption was estimated by the following formula: % adsorption = 100 — [(CO â‚ ¬Ã¢â‚¬â„¢C)/ C0] Where: C0 is the initial concentration of dye solution and C is the concentration of dye solution after Adsorption( S. Dhananasekaran et al,2015). RESULTS AND DISCUSSION Extraction of chitin from crab requires harsh chemical treatments. The crab shells even though contains majority of chitin, also has proteins and minerals. Proteins are removed by deproteinization and carbon and other salts are removed by demineralization( Badawy et al,2011). Process I â€Å" Solubility test for sample 1 Initial weight of chitin was measured to be 0.40 gram. Final weight of chitin after reaction with 1% acetic acid was measured to be 0.22 grams and hence the total dissolved weight of chitin was calculated to be 0.18 grams. Proecss II Solubility test for sample 2 Initial weight of chitin produced was measured to be 0.40 grams .Final weight of shells after reaction with 1% acetic acid was measured to be 0.20 grams and hence the total dissolved weight of chitin was calculated to be 0.20 grams. Therefore, it was observed that chitin produced employing Process II was more readily soluble in 1% acetic acid solution then that produced through Process I. FTIR Analysis- The interpretation of FTIR analysis of the samples is done for the possible presence of functional groups and the details are given in Table 1(Dhananasekaran S et al,2016) Table 1 Sr.no Standard chitin wavelength in cm-1 Crab chitin wavelength in cm-1 Groups Sample-1 Sample-2 1. 3300-3250 3373 3278 N-H 2. 2891 2952 2920,2826 C-H 3. 1680-1660 1653 1647 C=O 4. 1560-1530 1560 1568 Amide 5. 1072 1017 1024,1094 C-0-C 6. 952 952 901 Amide III 7. 750-650 667,625 685,617 N-H The FT-IR spectra of chitin isolate from crab shell are given in Figure 2 and 3 Theoreitically,? ±-chitin is characterized by three characteristic amide bands appearing at 1650,1620, and 1550 cm-1.In this study we observed FTIR bands at 1653 cm-1 and 1560 cm-1 for chitin sample 1 in figure 2.Here peak at 1653 cm-1 corresponds to symmetrical deformation to vibration of amide I band stretching C=O and 1560 cm-1 Coressponds to N-H deformation of amide II(Muhammed, R., et al,2010) FIG 2: FT-IR spectra of chitin (Sample 1) FIG 3: FT-IR spectra of chitin(Sample2) In sample 2,Figure 3 the peaks are observed at 1647 cm-1 and 1568 cm-1 which corresponds to symmetrical deformation to vibration of amide I band stretching C=O and N-H deformation of amide II respectively. From interpretation of FT IR it can be said that all functional groups which are during synthesis have been identified in the form of peaks that include amide,carbonyl and hydroxyl groups.This indicates the successive formation of chitin biopolymer(Muhammed, R., et al) Dye adsorption by Extracted Chitin Graph 1:Effect of pH on removal of dye Graph 2:Effect of contact time on removal of dye Graph 1 shows the relationship between pH values and percentage removal of dye .The readings were taken having varying pH between 4-9 and between intervals of 30 minutes. A result shows that the effectiveness of dye adsorption onto chitin was decreasing along with the increasing pH value. Here, the effect of dye adsorption is found maximum at pH7 i.e the neutral. The dye removal percentage with contact time between dye and extracted chitin is shown in Graph 2. The range of observed contact time was 30 -180 minutes with the increment of 30 minutes. It is observed that with increase in incubation time the effectiveness of dye adsorption by chitin increases. The % removal was found to be maximum at 180 minutes at pH 7 such as after 3 hours compared to initial readings. The % removal was found to be 39% after 180 minutes. CONCLUSION Chitin is one of the most abundant biopolymers in nature and is a major component in the supporting tissues of organisms such as crustaceans, fungi, and insects. It has wide application in various fields. This study shows the production of chitin from crab shell. The FTIR and chemical characterization studies confirm the production of chitin. In this study removal of dyes by adsorption using crab shell(chitin) was investigated. This study monitored the ability of chitin for removing dyes from aqueous solutions. Interaction between the chitin and dye were found to be strongly dependent on pH of the solution. The maximum percentage of dyes reduction was obtained at an optimum contact time 180 minutes and optimum pH of 7.Crab shell chitin has been found to be comparatively better adsorbent because it can remove almost 39 % of dyes within 3 hours. Finally, the result of adsorption study, it is concluded that chitin can be used as a coagulant of dyes because of its higher adsorptive capac ity, cost effectiveness, environment friendly behavior and availability in nature.

Similarities Between The Odyssey and The Aeneid - 824 Words

The Odyssey and Aeneid Long ago, there were two powerful nations located in southern Europe. First there were the Greeks, this nation was known for the first practice of democracy. Other than democracy, during the Greeks era there was a man by the name Homer who wrote a story called The Odyssey about a great legendary hero named Odysseus. After the Greeks, then came the Romans who ruled Greece for centuries. The Romans during their time were known to have practiced and used many of the Greeks cultures and theories. There was a Roman named Virgil who wrote about the beginning of the Romans. He created a story called The Aeneid; this story was about a Trojan who escaped a losing war to find a new home and peace. Even though these two stories may be hard to understand, Homer and Virgil are making statements about their nation after the Trojan War, because Odysseus was a legendary Greek king and Aeneas of Troy was known to be a beginning of the Romans. Homer and Virgil had used character s from the Trojan War as heroes. Homer used Odysseus as the protagonist, while Virgil chose Aeneas as his main character. Both these two were similar because they both symbolize a great hero for their nation. Odysseus was known as a heroic Greek king who helped defeat the Troy. His wooden horse idea was the only reason the Greeks overcame the favored Trojans. Aeneas was a hero as well, but was known more by the Romans. After Troy fell, Aeneas was looking for a new home and peace. 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Laughter Workshop free essay sample

Laughter and jokes can be explained differently towards anyone. Some people may say that laughter isn’t just caused by jokes and that jokes are not important for laughter. In Tickling the Naked Ape: The Science of Laughter, by Jimmy Carr and Lucy Greeves they quoted, â€Å"Why do Human Beings tell jokes? To make each other laugh. † (37) There are many dimensions to laughing and joking that can also have effects on people that connect with the joke. The argument for laughter and why people tell jokes cannot be solved because there are different views of what is funny or not. Furthermore, laughter and joking can explain understanding and can create an impact when perceived correctly. Laughter has always been around even before humans could speak. Human and apes share similar characteristics, when someone tickles a human baby or baby chimp they expressed their emotions through laughter. Some may argue that laughing is not a hard concept to learn. We will write a custom essay sample on Laughter Workshop or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page In the article Researcher Roger Fouts claimed that one of his subjects, a chimpanzee name Washoe, once urinated down his neck while riding on his shoulders, then made the sign for funny(38). Although this statement may seem that apes may also understand humor but what apes differ from humans is human intellect towards jokes. The ape may found humor to that situation but a practical joke is different from a joke with concept that needs verbal communication and intellect. An ape cannot tell a joke that has riddles or a story to it but a human can. The article states that laughter is a release of tension (36). To some critics they may not agree with this theory. They may argue that laughing cant create an effect that will change a person physically. To some people it may not have an effect but the text talks about some physical benefits that laughter can create. The article states a recent study by Professor Robert Dunbar found laughter raised peoples pain thresholds. Another study claimed that people who laugh more have healthier immune systems. A third experiment appeared to show that the increase in heart rate produced by a good laugh had health benefits equivalent to fifteen minutes on an exercise bike (42). These studies may not have the answers for cures but laughing to help you think of something positive and get someones ind off pain or try and help the body become healthier is good medicine. Although, laughing can release some tension and create positive effects so can joking. If a person is down and not in a good mood a friend wants to try and do their best to turn that negative emotion into a positive one maybe by joking around. Critics may believe differently, some may think that if a person is depressed that they w ill not want to laugh and they will just stay in a negative state. Anthropologist Terrance Deancon stated that laughter is not just an expression of emotion. It is a pubic symptom of engaging in a kind of mental conflict resolution. (44) The article also goes on and talks about a laughter workshop that helps people with anxiety and depression. When first starting off at the meeting some people cannot get themselves to attend because of their symptoms, but gradually continue with the program. This program helps patients become more at ease and teaches them that joking can help release anxiety and help become positive. Patients can use what the laughter workshop has taught them and use it in the outside world. Joking is not just about making someone laugh but it can give encouragement to someone that is not used to it. In conclusion, although there are many ways laughter and joking around can be expressed. From sharing the same characteristics with an ape through tickling a baby ape and a human baby to see them laugh and understanding the effects that laughing and joking can have on someone. Some may not agree but these reasons answer the question why human beings tells jokes. Works Cited Carr, Jimmy and Greeves, Lucy. Tickling the Naked Ape: The Science of Laughter. Laughing Matters. Ed. Marvin Diogenes. New York: Pearson/Longman, 2009. p. 37-49. Print.

House Safety Training-Free-Samples for Students-Myassignmenthelp

Question: Discuss about the House Safety Training to Produce Desired Safety Outcomes. Answer: Aims and Objectives The paper aims to help the researcher to find out why in-house safety training fails to produce the desired level of safety outcome. The actions that are taken during the in-house training programmer are also analyzed in this paper. The objective of the paper is as follows: To investigate the reason for the failure of in-house safety training To assess the impact of in-house training programme on the desired level of safety outcome To classify the factors which are responsible for the success of in-house safety training programme. Literature Review According to Ju and Rowlinson (2014),the various occupational accidents disrupts the entire production process and generates a huge amount of accident cost. The in-house safety personnels are not provided with adequate training and thus they fail to handle the situation. There are several serious accidents which causes huge financial loss to the company. The in-house personnels who provide safety-training programmes are suspended in times of such accidents. The staffs face several difficulties in providing and managing safety at the workplace. These safe behaviors pose a serious challenge to the employees and thus immediate reinforcement is required to deal with such situations. Moreover, the in-house staff has to conform with the minimum standards which is prescribed by the safety regulation. In certain cases, the housekeeping and the work access issues are mentioned by the clients and the workers and this issues leads to serious problem in the organization. The in-house staffs are not pro-active to deal with the various issues and it leads to serious accidents. change in the organization. The lack of commitment and the lack of prioritization of the work leads to conflict among the workers and this creates further problem in the organization. There must be different set of legislations which are necessary to enhance the skills of the in-house personnels. The health and safety issues of the employees are the main concern of the in-house training staffs. The strategic occupational health activities must be handled by the in-house staffs very carefully. Copper et al.(2015), the ineffective leadership style of the in-house training staff hinders the effectiveness of the organization. This affects the safety behavior, attitudes and it helps to reduce the injury rate. These contributes to further productivity and thus it helps in reducing the production bottleneck. The operational and safety management of any company goes hand-in-hand and the in-house staff must try to control and provide remedies to reduce various accidents. The in-house staffs believe in safety and this is reflected by their work. Due to miscommunication and mismanagement between the employees and in-house staffs, the in-house staffs are not provided with proper training facilities and they cannot provide service at the time of emergency. Rationale The study is important in this present generation because various hazardous accidents and risk prone activities are occurring around the world. It is necessary to take acre of the employees when they are undergoing any risk prone job. Preventing accidents and ill health that are caused by various work related activities is the key responsibility of every employee. The in-house training staff must be provided with adequate training to ensure safety and healthy working environment in the organization. Proper training for handling the various tools and techniques is important for the in-house staff so as to ensure safety within the organization. Learning Outcomes These learning module will help the students to analyze the importance of in-house training programme in the organization. It will help them To find out and analyze the learning solutions which are designed to ensure how safety adds value to the organiastion. Why it is important to identify the gaps in the organization so as to ensure safety and security of the employees? What are the methods that are used by the in-house staff for the safety of the employees? To analyze the safety and the health training practices of the employers having disease control programs Study design The study will be carried out through the use of primary surveys and secondary data of certain organizations. The researcher will interview the in-house staffs of various organizations who are associated with health and safety programs through the use of primary surveys. The employees will be interviewed and they will be asked to fill up the questionnaire. Based upon that, the research study will be carried out. On the other hand, the secondary data published by various health and occupational centers will also be taken and analyzed. This will help the researcher to make a comparison of the future risk and uncertainties that may affect the organization in the long run. The researcher will choose exploratory research. In this type of data, the researcher will explore the secondary data and make an interpretation of the data to reach valid conclusion (McNeil et al. 2015). Method of investigation The data will be collected through questionnaires and interviews. The questionnaires will be prepared by the researcher and distributed to the in-house staffs of various companies. These in-house staff will fill their responses and the researcher will make a close analysis and comparison between the responses given by the in-house staffs of various companies. These questionnaires will be distributed to 4 in-house staffs of 5 different construction companies. The data collected from different companies will help the researcher to compare and critically analyze the data. It will help the researcher to reach a conclusion and thus find out adequate measures to provide proper training to the in-house staffs (Chance and Brooks 2015). Ethics It is important to follow an ethical approach in the study and ensure reliability and validity . The research will be based on ethical approach. It will be ensured that the participants are not forced to give up the information. The purpose and the reason for data gathering will be fully disclosed to the participants and they will also get the freedom to quit the survey process whenever they want. It must also be ensured that the work done will not be plagiarized and the data that has been gathered is not manipulated. This will help the researcher to fulfill the research objectives (Bryman and Bell 2015). Risk There are various risk which has to be faced by the in-house staffs of a construction company. The staffs are allocated in the construction of high buildings that poses a great risk in their life. They must be provided with proper safety equipments and life jackets so that they do not suffer any head injury during the construction process. The family members must also be well aware of the construction sites in which the employees are engaged so that it will be easier to communicate with them in times of emergency (Harris and McCaffer 2013). Resource Required There are various resources which are necessary for the in-house staffs of the construction company. They may require life jackets, helmets and tools to protect themselves from risk and dangers. The companies in which they are engaged will bear the cost. They will bear the travel cost and the insurance of the employees when they are engaged in critical infrastructure projects (Walker 2015). Programme diary Activities Week 1 Week 2 Week 3 Week 3 Week 4 Week 5 Week 6 Selection of the topic Literature review and study of existing theories Data collection- primary Data Analysis Preparing Draft report Final Submission References Bryman, A. and Bell, E., 2015. Business research methods. New York: Oxford University Press. Chance, D.M. and Brooks, R., 2015.Introduction to derivatives and risk management. Cengage Learning. Cooper, D., 2015. Effective safety leadership: Understanding types styles that improve safety performance.Professional Safety,60(2), p.49. Harris, F. and McCaffer, R., 2013.Modern construction management. John Wiley Sons. Ju, C. and Rowlinson, S., 2014. Institutional determinants of construction safety management strategies of contractors in Hong Kong.Construction Management and Economics,32(7-8), pp.725-736. McNeil, A.J., Frey, R. and Embrechts, P., 2015.Quantitative risk management: Concepts, techniques and tools. Princeton university press. Seim, R., Poulsen, S. and Broberg, O., 2014. New developments in occupational health and safety management in Danish companies. In11th International Symposium on Human Factors. Walker, A., 2015.Project management in construction. John Wiley Sons.