ABSTRACT
Plastic waste poses a critical environmental challenge for the world. The proliferation of waste plastic coffee pods exacerbates this issue. Traditional disposal methods such as incineration and landfills are environmentally unfriendly, necessitating the exploration of alternative management strategies. One promising avenue is the pyrolysis in-line reforming process, which converts plastic waste into hydrogen. However, traditional pyrolysis methods are costly due to inefficiencies and heat losses. To address this, for the first time, our study investigates the use of microwave to enhance the pyrolysis process. We explored microwave pyrolysis for polypropylene (PP), high-density polypropylene (HDPE), and waste coffee pods, with the latter primarily comprising polypropylene. Additionally, catalytic ex-situ pyrolysis of coffee pod pyrolysis over a nickel-based catalyst was investigated to convert the evolved gas into hydrogen. The single-stage microwave pyrolysis results revealed the highest gas yield at 500 °C for HDPE, and 41 % and 58 % (by mass) for waste coffee pods and polypropylene at 700 °C, respectively. Polypropylene exhibited the highest gaseous yield, suggesting its readiness for pyrolytic degradation. Waste coffee pods uniquely produced carbon dioxide and carbon monoxide gases because of the oxygen present in their structure. Catalytic reforming of evolved gas from waste coffee pods using a 5 % nickel loaded activated carbon catalyst, yielded 76 % (by volume) hydrogen at 900 °C. These observed results were supported by elemental balance analysis. These findings highlight that two-stage microwave and catalysis assisted pyrolysis could be a promising method for the efficient management of waste coffee pods, particularly for producing clean energy.
Subject(s)
Coffee , Hydrogen , Microwaves , Polyethylene , Polypropylenes , Pyrolysis , Polypropylenes/chemistry , Hydrogen/chemistry , Coffee/chemistry , Catalysis , Polyethylene/chemistry , Refuse Disposal/methodsABSTRACT
OBJECTIVES: To identify associations between mortality in cSLE patients and their characteristics: clinical and laboratory features, disease activity and damage scores, and treatment; to evaluate risk factors associated with mortality in cSLE; and to determine the most frequent causes of death in this group of patients. METHODS: We performed a multicenter retrospective cohort using data from 1,528 cSLE patients followed in 27 pediatric rheumatology tertiary centers in Brazil. Patients' medical records were reviewed according to a standardized protocol, in which information regarding demographic and clinical features, disease activity and damage scores, and treatment were collected and compared between deceased cSLE patients and survivors. Univariate and multivariate analyses by Cox regression model were used to calculate risk factors for mortality, whereas survival rates were analyzed by Kaplan-Meier plots. RESULTS: A total of 63/1,528 (4.1%) patients deceased, 53/63 were female (84.1%), median age at death was 11.9 (9.4-13.1) years and median time interval between cSLE diagnosis and death was 3.2 (0.5-5.3) years. Sepsis was the main cause of death in 27/63 (42.8%) patients, followed by opportunistic infections in 7/63 (11.1%), and alveolar hemorrhage in 6/63 (9.5%) patients. The regression models resulted in neuropsychiatric lupus (NP-SLE) (HR = 2.56, 95% CI = 1.48-4.42) and chronic kidney disease (CKD) (HR = 4.33, 95% CI = 2.33-4.72), as risk factors significantly associated with mortality. Overall patient survival after cSLE diagnosis at 5, 10, and 15 years were 97%, 95.4%, and 93.8%, respectively. CONCLUSIONS: This study confirmed that the recent mortality rate in cSLE in Brazil is low, but still of concern. NP-SLE and CKD were the main risk factors for mortality, indicating that the magnitude of these manifestations was significantly high.
Subject(s)
Lupus Erythematosus, Systemic , Renal Insufficiency, Chronic , Child , Humans , Female , Male , Lupus Erythematosus, Systemic/complications , Brazil/epidemiology , Retrospective Studies , Age of Onset , Risk Factors , Renal Insufficiency, Chronic/complicationsABSTRACT
OBJECTIVE: To evaluate symptomatic polyautoimmunity (PA) at childhood-onset systemic lupus erythematosus(cSLE) diagnosis, and its association with demographic data, disease activity, clinical manifestations and laboratorial abnormalities in a large Brazilian cSLE population. METHODS: A multicenter retrospective study was performed in 1463 cSLE(ACR criteria) patients from 27 Pediatric Rheumatology services. Symptomatic PA was defined according to the presence of more than one concomitant autoimmune disease(AD) and symptomatic multiple autoimmune syndrome(MAS) was defined as three or more AD. An investigator meeting was held to define the protocol. Demographic data, SLICC classification criteria and SLEDAI-2K were evaluated. RESULTS: At cSLE diagnosis symptomatic PA was observed in 144/1463(9.8%) and symptomatic MAS occurred in solely 10/1463(0.7%). In the former group the more frequently observed associated AD were Hashimoto thyroiditis nâ¯=â¯42/144(29%), antiphospholipid syndrome nâ¯=â¯42/144(29%), autoimmune hepatitis nâ¯=â¯26/144(18%) and type 1 diabetes mellitus nâ¯=â¯23/144(15.9%). Further comparisons between cSLE patients with and without PA showed a higher median age(pâ¯=â¯0.016) and lower mean SLICC criteria (pâ¯=â¯0.039) in those with PA. Additionally, these cSLE patients had less renal involvement(35% vs. 44%, pâ¯=â¯0.038) and red blood cell cast(6% vs. 12%, pâ¯=â¯0.042) and more antiphospholipid antibodies(29% vs. 15%, pâ¯<â¯0.0001). CONCLUSIONS: Approximately 10% of cSLE had symptomatic PA at diagnosis, particularly endocrine autoimmune disorders and antiphospholipid syndrome. Lupus was characterized by a mild disease onset and MAS was infrequently evidenced. Further studies are necessary to determine if this subgroup of cSLE patients have a distinct genetic background with a less severe disease and a better long-term outcome.