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2.
Waste Manag ; 57: 226-234, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26783101

RESUMO

The possibilities and limits of pyrolysis as a means of recycling plastic rich fractions derived from discarded phones have been studied. Two plastic rich samples (⩾80wt% plastics) derived from landline and mobile phones provided by a Spanish recycling company, have been pyrolysed under N2 in a 3.5dm3 reactor at 500°C for 30min. The landline and mobile phones yielded 58 and 54.5wt% liquids, 16.7 and 12.6wt% gases and 28.3 and 32.4wt% solids respectively. The liquids were a complex mixture of organic products containing valuable chemicals (toluene, styrene, ethyl-benzene, etc.) and with high HHVs (34-38MJkg-1). The solids were composed of metals (mainly Cu, Zn, and Al) and char (≈50wt%). The gases consisted mainly of hydrocarbons and some CO, CO2 and H2. The halogens (Cl, Br) of the original samples were mainly distributed between the gases and solids. The metals and char can be easily separated and the formers may be recycled, but the uses of the char will be restricted due to its Cl/Br content. The gases may provide the energy requirements of the processing plant, but HBr and HCl must be firstly eliminated. The liquids could have a potential use as energy or chemicals source, but the practical implementation of these applications will be no exempt of great problems that may become insurmountable (difficulty of economically recovering pure chemicals, contamination by volatile metals, etc.).


Assuntos
Telefone Celular , Resíduo Eletrônico , Plásticos , Reciclagem/métodos , Bromo , Cloro , Gases , Mercúrio
3.
Waste Manag ; 33(1): 52-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23098814

RESUMO

In this paper rejected streams coming from a waste packaging material recovery facility have been characterized and separated into families of products of similar nature in order to determine the influence of different types of ingredients in the products obtained in the pyrolysis process. The pyrolysis experiments have been carried out in a non-stirred batch 3.5 dm(3) reactor, swept with 1 L min(-1) N(2), at 500°C for 30 min. Pyrolysis liquids are composed of an organic phase and an aqueous phase. The aqueous phase is greater as higher is the cellulosic material content in the sample. The organic phase contains valuable chemicals as styrene, ethylbenzene and toluene, and has high heating value (HHV) (33-40 MJ kg(-1)). Therefore they could be used as alternative fuels for heat and power generation and as a source of valuable chemicals. Pyrolysis gases are mainly composed of hydrocarbons but contain high amounts of CO and CO(2); their HHV is in the range of 18-46 MJ kg(-1). The amount of COCO(2) increases, and consequently HHV decreases as higher is the cellulosic content of the waste. Pyrolysis solids are mainly composed of inorganics and char formed in the process. The cellulosic materials lower the quality of the pyrolysis liquids and gases, and increase the production of char.


Assuntos
Temperatura Alta , Embalagem de Produtos , Reciclagem , Catálise , Gases/análise , Alcatrões/análise
7.
Waste Manag ; 32(5): 826-32, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21795037

RESUMO

Pyrolysis may be an alternative for the reclamation of rejected streams of waste from sorting plants where packing and packaging plastic waste is separated and classified. These rejected streams consist of many different materials (e.g., polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), aluminum, tetra-brik, and film) for which an attempt at complete separation is not technically possible or economically viable, and they are typically sent to landfills or incinerators. For this study, a simulated plastic mixture and a real waste sample from a sorting plant were pyrolyzed using a non-stirred semi-batch reactor. Red mud, a byproduct of the aluminum industry, was used as a catalyst. Despite the fact that the samples had a similar volume of material, there were noteworthy differences in the pyrolysis yields. The real waste sample resulted, after pyrolysis, in higher gas and solid yields and consequently produced less liquid. There were also significant differences noted in the compositions of the compared pyrolysis products.


Assuntos
Plásticos , Embalagem de Produtos , Eliminação de Resíduos/métodos , Gerenciamento de Resíduos/métodos , Gases , Temperatura Alta , Plásticos/química , Polietilenotereftalatos/química , Polietilenos/química , Polipropilenos/química , Poliestirenos/química , Cloreto de Polivinila/química
8.
Artigo em Inglês | MEDLINE | ID: mdl-21995183

RESUMO

Drug-induced aseptic meningitis (DIAM) is a diagnostic challenge. The major causative agents are nonsteroidal anti-inflammatory drugs (particularly ibuprofen), antibiotics, intravenous immunoglobulin, and OKT3 monoclonal antibodies. DIAM is more frequently observed in patients with autoimmune diseases. A 36-year-old woman was attended in our department 3 months after being diagnosed with aseptic meningoencephalitis. She had had 2 episodes in 9 months. Neurological symptoms were associated with ibuprofen. A challenge with acetylsalicylic acid was negative, whereas a drug challenge with ibuprofen was positive. Thirty minutes after ingesting 50 mg of ibuprofen, she experienced general malaise and progressively developed chills, fever (39.5 degrees C), headache, and nuchal rigidity. Lumbar puncture showed normal glucose and high protein levels. Neutrophilic pleocytosis was observed at the first admission; lymphocytosis was predominant in the second and third episodes. DIAM is a rare and severe hypersensitivity reaction. Drug challenge enabled us to make an accurate diagnosis.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Ibuprofeno/efeitos adversos , Meningite Asséptica/induzido quimicamente , Meningoencefalite/induzido quimicamente , Adulto , Feminino , Humanos , Meningite Asséptica/fisiopatologia , Meningoencefalite/fisiopatologia
9.
Waste Manag ; 31(9-10): 1973-83, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21689920

RESUMO

In this work, the results obtained in catalytic pyrolysis of three plastic waste streams which are the rejects of an industrial packing wastes sorting plant are presented. The samples have been pyrolysed in a 3.5 dm(3) reactor under semi-batch conditions at 440 °C for 30 min in nitrogen atmosphere. Commercial ZSM-5 zeolite has been used as catalyst in liquid phase contact. In every case, high HHV gases and liquids which can be useful as fuels or source of chemicals are obtained. A solid fraction composed of the inorganic material contained in the raw materials and some char formed in the pyrolysis process is also obtained. The zeolite has shown to be very effective to produce liquids with great aromatics content and C3-C4 fraction rich gases, even though the raw material was mainly composed of polyolefins. The characteristics of the pyrolysis products as well as the effect of the catalyst vary depending on the composition of the raw material. When paper rich samples are pyrolysed, ZSM-5 zeolite increases water production and reduces CO and CO(2) generation. If stepwise pyrolysis is applied to such sample, the aqueous liquid phase can be separated from the organic liquid fraction in a first low temperature step.


Assuntos
Temperatura Alta , Plásticos/química , Gerenciamento de Resíduos/métodos , Catálise , Cloro/química , Gases/análise , Termogravimetria , Resíduos/análise , Água
10.
Waste Manag ; 31(8): 1852-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21530221

RESUMO

In this work, a study of the regeneration and reuse of ZSM-5 zeolite in the pyrolysis of a plastic mixture has been carried out in a semi-batch reactor at 440°C. The results have been compared with those obtained with fresh-catalyst and in non-catalytic experiments with the same conditions. The use of fresh catalyst produces a significant change in both the pyrolysis yields and the properties of the liquids and gases obtained. Gases more rich in C3-C4 and H(2) are produced, as well as lower quantities of aromatic liquids if compared with those obtained in thermal decomposition. The authors have proved that after one pyrolysis experiment the zeolite loses quite a lot of its activity, which is reflected in both the yields and the products quality; however, this deactivation was found to be reversible since after regeneration heating at 550°C in oxygen atmosphere, this catalyst recovered its initial activity, generating similar products and in equivalent proportions as those obtained with fresh catalyst.


Assuntos
Plásticos/química , Gerenciamento de Resíduos/métodos , Zeolitas/química , Catálise , Reciclagem/métodos
11.
Waste Manag ; 30(4): 620-7, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19926462

RESUMO

The objective of this work is the study of pyrolysis as a feedstock recycling process, for valorizing the rejected streams that come from industrial plants, where packing and packaging wastes are classified and separated for their subsequent mechanical recycling. Four real samples collected from an industrial plant at four different times of the year, have been pyrolysed under nitrogen in a 3.5dm(3) autoclave at 500 degrees C for 30min. Pyrolysis liquids are a complex mixture of organic compounds containing valuable chemicals as styrene, ethyl-benzene, toluene, etc. Pyrolysis solids are composed of the inorganic material contained in the raw materials, as well as of some char formed in the pyrolysis process, and pyrolysis gases are mainly composed of hydrocarbons together with some CO and CO(2), and have very high gross calorific values (GCV). It has been proved by the authors that the composition of the raw material (paper, film, and metals contents) plays a significant role in the characteristics of pyrolysis products. High paper content yields water in the pyrolysis liquids, and CO and CO(2) in the gases, high PE film content gives rise to high viscosity liquids, and high metals content yields more aromatics in the liquid products, which may be attributed to the metals catalytic effect.


Assuntos
Fontes Geradoras de Energia , Temperatura Alta , Incineração , Resíduos Industriais , Plásticos/química , Dióxido de Carbono/análise , Monóxido de Carbono/análise , Catálise , Cidades , Conservação dos Recursos Naturais , Gases/análise , Resíduos Industriais/análise , Metais/análise , Metais/química , Papel
12.
J Investig Allergol Clin Immunol ; 19 Suppl 2: 56-60, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19530420

RESUMO

BACKGROUND: There are infrequent or unspecific diseases that occupy an important part of time in the job of the allergists. OBJECTIVE: We sought to evaluate the frequency and to determine the characteristics of uncommon or unspecific diseases seen by allergists in Spain, and to compare these data with findings obtained in a similar study undertaken in 1992. MATERIAL AND METHODS: An observational, prospective and cross-sectional study named "Alergológica 2005" was carried out in Spain. A part of this study analyzed the demographic, healthcare and clinical aspects of infrequent or unspecific diseases categorized as "Other allergic diseases" (OAD) or "Other non-allergic diseases" (ONAD). RESULTS: The survey comprised 4991 patients. In OAD, 45 patients were included. In ONAD, 290 patients were included. Significant diagnoses were gastroallergic anisakiasis (10 patients), idiopathic anaphylaxis (7 patients), and hypersensitivity pneumonitis (2 patients). In the ONAD group, non allergic respiratory diseases were the most frequent diagnosis. Mean time spent to reach a diagnosis was 14.2 days. However, the median of this time was only 1 day. Main diagnostic methods employed were a clinical history/physical examination in 86% of patients and skin tests in 73.7%. CONCLUSION: Several unspecific diseases affected more than 60% of patients in the two groups together. Findings show the current knowledge of allergic disorders due to Anisakis simplex. Diagnoses of hypersensitivity pneumonitis seem to be as frequent as previously published. Idiopathic anaphylaxis seems to be less frequent. The wide-range of times needed to reach a diagnosis was in agreement with the mixture of diseases included in both groups.


Assuntos
Hipersensibilidade/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Hipersensibilidade/diagnóstico , Hipersensibilidade/terapia , Lactente , Masculino , Pessoa de Meia-Idade , Prevalência , Qualidade de Vida , Espanha/epidemiologia
15.
Allergol Immunopathol (Madr) ; 33(5): 288-90, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16287550

RESUMO

BACKGROUND: Few previous reports of carrot-induced asthma have been confirmed by objective tests. Hypersensitivity to carrot is frequently associated with allergy to Apiaceae spices and sensitization to birch and mugwort pollens. CLINICAL CASE: A 40-year-old cook woman was seen with sneezing, rhinorrhea, contact urticaria and wheezing within few minutes of handling or cutting raw carrots. She needed to leave out of the kitchen while the other cooks cut raw carrots. METHODS AND RESULTS: Skin tests were positive to carrot, celery, aniseed and fennel. Rubbing test with fresh carrot was positive. Specific IgE to carrot was 4.44 kU/L. Determinations of specific IgE to mugwort, grass and birch pollens were negative. Inhalative provocation test, performed as a handling test, was positive. The IgE-immunoblotting showed two bands in carrot extract: a band with apparent molecular weight of 30 kd and other band of 18 kd. This band of 18 kd was Dau c 1. The band of 30 kd could correspond a phenylcoumaran benzylic ether reductase. Dau c 1 did not appear to be the unique allergen in this case. Additional allergens may induce the sensitization. Primary sensitization due to airborne allergens of foods and the lack of pollen allergy in this patient are notorious events.


Assuntos
Asma/etiologia , Daucus carota/efeitos adversos , Manipulação de Alimentos , Doenças Profissionais/etiologia , Adulto , Apium/efeitos adversos , Tosse/etiologia , Feminino , Humanos , Prurido/etiologia , Testes Cutâneos , Urticária/etiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-15301309

RESUMO

Hypersensitivity pneumonitis or extrinsic allergic alveolitis can be defined as a lung disease caused by a wide group of antigens that reach the lung by inhalation of organic and/or inorganic dust of various sources. The dust of the stored maize corn has been reported as cause of respiratory symptoms. During the storage process, maize corn dust can be contaminated by moulds and thermophilic actinomycetes, which have not been described until now as the causing antigens of these symptoms. We present a case of occupational hypersensitivity pneumonitis in an agricultural worker who cultured and stored maize corn. Clinical findings, precipitating antibodies, and evolution after having removed him from his work, confirmed the diagnosis. In our case, Aspergillus species contaminating the maize corn dust are probably the antigens that caused the disease.


Assuntos
Doenças dos Trabalhadores Agrícolas/microbiologia , Alveolite Alérgica Extrínseca/microbiologia , Aspergilose/imunologia , Aspergillus/imunologia , Zea mays/microbiologia , Doenças dos Trabalhadores Agrícolas/imunologia , Agricultura , Alveolite Alérgica Extrínseca/imunologia , Aspergilose/microbiologia , Poeira/imunologia , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Pessoa de Meia-Idade , Zea mays/imunologia
17.
Allergol Immunopathol (Madr) ; 32(2): 86-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15087096

RESUMO

Immune abnormalities have been found in many patients receiving anti-epileptic drugs. However, the effects of carbamazepine are still conflicting. We report the case of a 31-year-old woman who began carbamazepine treatment because of idiopathic epilepsy of adulthood. After three years of treatment she developed arthralgias and malaise. Complete immunologic evaluation showed a total absence of immunoglobulin M with decreased levels of immunoglobulin A, positive antinuclear antibodies and monoclonal paraproteinemia type IgG-kappa. The possibility of B cell lymphoma or myeloma was ruled out. Skin testing was negative. Bone marrow examination was normal. After carbamazepine discontinuation, levels of IgA and IgM increased until reaching normal values over 3 years. The monoclonal gammopathy of undetermined significance also disappeared over this period. During this period of immunodeficiency, the patient did not complain of any infectious complications.


Assuntos
Agamaglobulinemia/induzido quimicamente , Anticonvulsivantes/efeitos adversos , Carbamazepina/efeitos adversos , Deficiência de IgA/induzido quimicamente , Imunoglobulina M/deficiência , Síndromes de Imunodeficiência/induzido quimicamente , Gamopatia Monoclonal de Significância Indeterminada/induzido quimicamente , Adulto , Medula Óssea/patologia , Diagnóstico Diferencial , Epilepsia/complicações , Epilepsia/tratamento farmacológico , Feminino , Humanos , Cadeias kappa de Imunoglobulina/sangue , Linfoma de Células B/diagnóstico , Gamopatia Monoclonal de Significância Indeterminada/diagnóstico , Mieloma Múltiplo/diagnóstico
19.
Artigo em Inglês | MEDLINE | ID: mdl-15736722

RESUMO

Inhalation of dust from different enzymes can be the cause of occupational asthma in exposed workers. Enzymes from different sources are being increasingly used in food. Few cases of food allergy to alpha-amylase induced by eating bread have been reported. Those cases were reported in bakery-related patients and in a pharmaceutical-industry worker. A 25-year-old farmer suffered sneezing, rhinorrhea, oropharyngeal itching, hoarseness, cough, and non-wheezy dyspnea after eating white bread. Skin prick tests (SPT) with common aeroallergens and food allergens revealed only sensitization to Olea europaea pollen. SPT response was positive to Aspergillus oryzae alpha-amylase. Specific IgE against alpha-amylase was positive. A double-blind placebo-controlled challenge with 5 mg of uncooked -amylase induced sneezing, cough, oral angioedema within 10 minutes. The provocation test with 50 g of white bread gave similar findings. This case indicates that alpha-amylase contained in bread may provoke IgE-mediated food allergy. It is worth noting that in this case, the only source of alpha-amylases sensitization was bread.


Assuntos
Angioedema/etiologia , Pão/efeitos adversos , Hipersensibilidade Alimentar/etiologia , alfa-Amilases/imunologia , Adulto , Humanos , Masculino , Testes Cutâneos
20.
Allergol Immunopathol (Madr) ; 31(6): 342-4, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14670290

RESUMO

Carboplatin (CP) hypersensitivity reactions have been reported in nearly 12 % of patients treated with this drug. The pathophysiologic mechanisms of these reactions have not been entirely elucidated. Various hypotheses are under discussion. CP hypersensitivity reactions could be IgE-mediated, caused by low-molecular platinum compounds acting as haptens. Platinum salts are also able to release histamine from basophils and mast cells, and some events seem to be non-immune-mediated direct histamine release. We report a case of CP tolerance induction in a 65-year-old man. During the third course of CP he experienced an anaphylactic reaction. Skin testing was negative. Suspecting the possibility of an anaphylactoid reaction due to histamine release, we developed a protocol to induce tolerance. Pre-medication with corticosteroid and antihistaminic was performed before intravenous CP infusion. The bag with CP was first infused 60 ml/h for 30 minutes; the infusion was well tolerated and infusion was continued at 100 ml/h for the next 60 minutes and thereafter at 120 ml/h until the bag was finished. Following this "desensitization", monthly courses of CP using the same protocol have been well tolerated.


Assuntos
Anafilaxia/induzido quimicamente , Antineoplásicos Alquilantes/efeitos adversos , Carboplatina/efeitos adversos , Clorfeniramina/uso terapêutico , Antagonistas dos Receptores Histamínicos H1/uso terapêutico , Hidrocortisona/uso terapêutico , Imunossupressores/uso terapêutico , Idoso , Anafilaxia/terapia , Antineoplásicos Alquilantes/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carboplatina/administração & dosagem , Carcinoma/tratamento farmacológico , Clorfeniramina/administração & dosagem , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Liberação de Histamina/efeitos dos fármacos , Humanos , Hidrocortisona/administração & dosagem , Imunossupressores/administração & dosagem , Infusões Intravenosas , Masculino , Metotrexato/administração & dosagem , Cuidados Paliativos , Pré-Medicação , Testes Cutâneos , Neoplasias Urológicas/tratamento farmacológico , Vimblastina/administração & dosagem
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