Production of liquid hydrocarbons by thermo-acidic method from waste high-density polyethylene.

AIMS: The study explains the production of useful liquid hydrocarbons by thermo-acidic catalytic thermal degradation of waste high-density polyethylene. A comparative study of the liquid samples with or without catalysts. BACKGROUND: Energy demand is high in the world. Waste plastic conversion is nowadays a concern of interest research for scientists. HDPE (High-density polyethylene) is the most common plastic used in households. Different types of catalysts and techniques have been used in the alteration process of waste HDPE. This paper deals with the kandite group of catalyst kaolin and the montmorillonite group of catalyst sodium bentonite in acid-activated mutated form. OBJECTIVE: This paper aims to explore the prominent utilization of kaolin clay and sodium bentonite clay minerals as a catalyst for the alteration of waste HDPE into fuel resources and to develop a cost-effective recycling experimental set-up for plastic waste conversion. METHOD: Thermo-catalytic acid activation has been done for clay mutation. Hydrochloric acid-activated catalysts have been used in this study. FT-IR (Fourier Transform Infrared Spectroscopy) and GC-MS (Gas Chromatography and Mass Spectrometer) techniques have been used to explore the prominent compounds in the product samples. RESULT: Maximum energy per photon for RO (Parent Oil/Raw Oil) and AO(Acid treated thermo-catalytic oil) samples are respectively 58034.01×1024 Joules and 59271.40×1024 Joules concerning wave numbers 2921.42 and 2983.71 cm-1. Compounds of functional groups C-CH3, CH2, alkenes, and CH3 have been identified for RO and AO samples. Less gaseous hydrocarbons 31.79% (outcomes) or 29.66 % (production yield) and 150.06 % of increment in wax have been calculated after using acid-treated catalysts. Aliphatic compounds like alkanes and alkenes are present in the samples. CONCLUSION: A mixture of acid-treated kaolin and acid-treated sodium bentonite as the catalysts for degrading waste HDPE into liquid oil greatly reduces wax formation. Average outcomes and production of liquid hydrocarbons are good results with the acid-treated catalytic degradation of HDPE waste. One remarkable fact is that the yield percentage of liquid products is higher in acid-activated catalytic thermal degradation.

Acid-activated Sodium Bentonite and Kaolin Clay: Comparative Study by Physicochemical Properties.

AIMS AND OBJECTIVE: This paper aims to reveal the useful industrial aspects of kandite and montmorillonite group of clays using as a catalyst after acid activation. A comparative study of modified characteristics of clay samples has been explored based on industrial requirements. MATERIALS AND METHODS: In this study sodium bentonite and kaolin clay have been focused. The modified characteristics of clay samples are investigated by characterization methods of FT-IR, XRD, SEM/EDAX, TGA and DSC before and after treated with 4M of Hydrochloric acid. Clay samples were refluxed at 105ºC and calcined at 500ºC consecutively for 3 hours at room temperature. RESULTS: Maximum crystalline size 104.02 nm has been evaluated for acid-activated sodium bentonite. Alkyl halides compounds have a strong band position for all samples and have more extent on acid activation. The small numbers of manganese particles have been noticed in the acidactivated samples. 14% of decrement and 61.02% of increment of aluminates have been found respectively for acid-activated kaolin and acid-activated sodium bentonite. CONCLUSION: The novelty of this study is about sodium bentonite characterization and the results show the prominent behaviour with structural, elemental, morphological, and thermal analysis. Acid-activated kaolin sample has less effect in comparison with acid-activated sodium bentonite. As the removal of the hydroxyl group of compounds has been reported through FT-IR and XRD analysis also some other industries like ceramic and paper industries may have accepted these types of modified minerals for special production with a simple process.

Utility of N-acetylcysteine in ischemic hepatitis in cirrhotics with acute variceal bleed: a randomized controlled trial.

BACKGROUND AND AIMS: Ischemic hepatitis (IH) following acute variceal bleed (AVB) carries an ominous prognosis. N-Acetylcysteine (NAC), a potent anti-oxidant, may prevent IH by improving tissue oxygen delivery and improving hepatic hypoxia. METHODS: Consecutive cirrhotics with AVB were prospectively randomized to receive either standard of care (SOC) plus NAC intravenously for 72 h(at 150 mg/kg/h for 1 h followed by 12.5 mg/kg/h for 4 h, followed by 6.25 mg/kg for 67 h) (Group A, n = 107) or SOC alone (Group B, n = 107). RESULTS: Baseline characteristics were comparable. IH developed more frequently in Gr.B 25(23%) than A-15(14%); p = 0.08). Incidence of IH increased with severity of liver disease. Binary logistic regression analysis showed reduced incidence of IH in Gr.A than B [odds ratio (OR) 0.33, 0.11-0.93] patients after controlling for other significant factors. The incidence of acute kidney injury (AKI) was also reduced in Gr.A [OR 0.34, 0.15-0.75]. Development of IH was significantly associated with increased deaths due to liver failure at 6 weeks [subdistribution hazard ratio (SHR) 21.6, 7.4-62.8]. On multivariate competing risk analysis, significantly lower deaths due to liver failure (SHR 0.33, 0.11-0.97) were noted in Gr.A than B. CONCLUSIONS: One in five patients with acute variceal bleed develops ischemic hepatitis which is associated with worse outcomes. NAC therapy averts deaths due to liver failure by preventing IH and reduces AKI and is, therefore, recommended for cirrhotics with acute variceal bleed. TRIAL REGISTRATION: Clinicaltrials.gov no: NCT02015403.

Physico-chemical Characterization of Hydrochloric Acid-treated Kaolin Clay: An Industry Approach as a Potential Catalyst.

AIMS AND OBJECTIVE: This study explains the FT-IR, XRD, XRF, SEM/EDX, TGA, and DSC/DTA characterization of commercially available kaolin clay. The objective of this paper is to explore the prominent utilization of kandites clay and useful chemical aspects for the modification of kaolin clay minerals. MATERIALS AND METHODS: The untreated kaolin sample has been procured in this experimental work from AksharChem, Gujrat, India. The kaolin clay was treated with 4M hydrochloric acid. FT-IR, XRD, XRF, SEM/EDX, TGA, and DSC/DTA characterization methods have been used. RESULTS: Loss on ignition was found at 10.89%. The fingerprint region of the acid-treated sample has broad and more bending vibrations than untreated samples. The high weight percentage of Ti and CaCO3 were spotted in the scanning electron micrograph by both atomic % and weight %. The FT-IR revealed the functional group of Al-O, A1-OH, and Si-O. CONCLUSION: The morphology indicates that the presences of large particles are in the form of agglomerates. It was found that impurity like scandium vanished and manganese traced by the same atomic % 0.01 of zinc which had no presence after acid treatment. Thermogravimetric analysis indicates the sharp increments in heat flow in-between temperatures 0°C to 200°C and consequently increments in between 500°C to 550°C, a suitable range for the pyrolysis. Low amount of alumina and high amount of silica has been found out. TGA and DTA analysis satisfy the waste plastic valorization temperature ranges.

Incidence, Risk Factors, and Outcomes of Transition of Acute Kidney Injury to Chronic Kidney Disease in Cirrhosis: A Prospective Cohort Study.

Transition to chronic kidney disease (CKD) after an episode of acute kidney injury (AKI) is known in patients without cirrhosis. We studied the incidence and risk factors for development of CKD in patients with cirrhosis. Competing risk analysis was performed to identify risk factors for CKD development. Of 818 patients with cirrhosis (age, 50.4 ± 11.8 years; 84% males; Model for End-Stage Liver Disease [MELD], 19.9 ± 9.9), 36% had AKI at enrollment, 27% had previous AKI, and 61% developed new episodes of AKI during the follow-up period. CKD developed in 269 (33%) patients. Serum cystatin C (CysC; subdistribution hazard ratio [SHR], 1.58; 1.07-2.33), episodes of previous AKI (SHR, 1.26; 1.02-1.56), and AKI stage at enrollment (no AKI [SHR, 1] vs. stage 1 [SHR, 3.28; 1.30-8.25] vs. stage 2 [SHR, 4.33; 1.76-10.66] vs. stage 3 [SHR, 4.5; 1.59-12.73]) were identified as baseline risk factors for CKD development. On time-varying competing risk analysis, MELD (SHR, 1.01; 1.00-1.03), number of AKI episodes (SHR, 1.25; 1.15-1.37), and CysC (SHR, 1.38; 1.01-1.89) predicted CKD development. Development of CKD was associated with higher risk of death. Reduction in glomerular filtration rate (GFR) not meeting CKD criteria was observed in 66% of patients with cirrhosis, more so in those with previous AKI episodes and a high CysC level and MELD score. Renal histology, available in 55 patients, showed tubulointerstitial injury in 86%, cholemic nephrosis in 29%, and glomerular changes in 38%. Conclusion: Almost two-thirds of patients with cirrhosis develop episodes of AKI and reduction in GFR; one-third progress to CKD, resulting in adverse outcomes. Higher MELD and CysC levels and number of AKI episodes predict development of CKD in patients with cirrhosis.

Cystatin C predicts acute kidney injury and mortality in cirrhotics: A prospective cohort study.

BACKGROUND & AIMS: Acute kidney injury is a frequent and ominous complication in cirrhosis. An episode of AKI damages the functional nephron mass, compromising the renal functional reserve. We aimed to study the incidence of AKI, probability of subsequent episodes, whether AKI itself predisposes to future AKI and the reliability of serum cystatin C(sCyC) as a biomarker in a prospective cohort of cirrhotics. PATIENTS AND METHODS: Five hundred and thirty-one cirrhotics without ongoing AKI were followed for development/resolution of AKI. Predictive models for AKI and mortality were developed and validated (Gr. A, Derivative cohort [n = 273], Gr. B, Validation Cohort [n = 258]). RESULTS: 365 episodes of AKI occurred in 233 patients; yielding a mean of 1.56 episodes of AKI per patient. In Gr. A and B, 97 (35.5%) and 78 (30%) patients had prior AKI episodes and were predisposed to further attacks (Gr. A, HR 3.9, 95% CI 2.7-5.6, Gr. B, HR 3.6, 95% CI 2.5-5.4). AKI was thus an independent predictor of the development of new AKI(P < .05) and this risk increased significantly with increase in the number of AKI episodes (P < .001). S.CysC but not s.Cr was an independent predictor of new AKI on multivariate analysis. "AKI-Score" incorporating CysC; and the addition of Cyst into components of MELD, that is the "MELD-Cystatin" score predicted the development of AKI and mortality, respectively, and performed significantly better than the MELD and CTP scores. CONCLUSIONS: An episode of AKI itself predisposes to subsequent attacks of AKI in cirrhotics. Scores incorporating CysC can accurately predict the development of AKI and mortality in these patients.

SX-Ella Stent Danis Effectively Controls Refractory Variceal Bleed in Patients with Acute-on-Chronic Liver Failure.

BACKGROUND AND AIMS: Almost 10% of bleeding episodes are refractory to combination of vasoactive agent and endotherapy, and are associated with a mortality up to 50%. Severity of liver disease and high portal pressure are mainly responsible for it. TIPS cannot be used in these patients due to high MELD score. We aimed to evaluate the efficacy of self-expandable DE stents for control of refractory variceal bleeds in patients with ACLF. METHODS: Acute-on-chronic liver failure patients (n = 88, mean age 47.3 ± 10.9 years) with refractory variceal bleeds received either DE stent (Gr. A, n = 35) or continued with repeat endotherapy and vasoactive drug (Gr.B, n = 53). Matching by propensity risk score (PRS) was done to avoid selection bias. Competing risk Cox regression analysis was done to identify event-specific, i.e., gastrointestinal bleed-related death. RESULTS: Majority (78.4%) of patients were alcoholic with MELD score of 45.9 ± 20.1. Control of initial bleeding was significantly more in the DE stent group as compared to controls in both pre-match (89 vs. 37%; p < 0.001) and PRS-matched cohorts (73 vs. 32%; 0.007). Further, bleed-related death was also significantly lower in DE group as compared to controls in both pre-match (14 vs. 64%; p = 0.001) and PRS-matched cohorts (6 vs. 56%; p = 0.001). In a multivariate competing risk Cox model, patients who underwent DE stenting had reduced mortality in both pre-match (p = 0.04, HR 0.36, 95% CI 0.13-0.96) and PRS-matched cohorts (p < 0.001, HR 0.21, 95% CI 0.08-0.51). CONCLUSIONS: Self-expandable DE stents are very effective in control of refractory variceal bleeding and reduced mortality in patients with severe liver failure.

Endoscopic treatment of gastric varices.

Gastric varices (GV) are present in one in 5 patients with portal hypertension and variceal bleeding. GV bleeds tend to be more severe with higher mortality. High index of suspicion, early detection and proper locational diagnosis are important. An algorithmic approach to the management of GV bleeding prevents rebleeds and improves survival. Vasoactive drugs should be started with in 30 minutes (door to needle time) and early endotherapy be done. Cyanoacrylate injection in experienced hands achieves hemostasis in >90% patients. A repeat session is sometimes needed for complete obturation of GV. Transjugular intrahepatic portosystemic shunt and balloon retrograde transvenous obliteration are effective rescue options. Secondary prophylaxis of GV bleeding is done with beta-blocker and endotherapy.