Deactivation study of the hydrodeoxygenation of p-methylguaiacol over silica supported rhodium and platinum catalysts

Hydrodeoxygenation of para-methylguaiacol using silica supported Rh or Pt catalysts was investigated using a fixed-bed reactor at 300 °C, under 4 barg hydrogen and a WHSV of 2.5 h−1. The activity, selectivity and deactivation of the catalysts were examined in relation to time on stream. Three catalysts were tested: 2.5% Rh/silica supplied by Johnson Matthey (JM), 2.5% Rh/silica and 1.55% Pt/silica both prepared in-house. The Rh/silica (JM) showed the best stability with steady-state reached after 6 h on stream and a constant activity over 3 days of reaction. In contrast the other two catalysts did not reach steady state within the timeframe of the tests, with continuous deactivation over the time on stream. Nevertheless higher coking was observed on the Rh/silica (JM) catalyst, while all three catalysts showed evidence of sintering. The Pt catalyst (A) showed higher selectivity for the production of 4-methylcatechol while the Rh catalysts were more selective toward the cresols. In all cases, complete hydrodeoxygenation of the methylguaiacol to methylcyclohexane was not observed

Surgical Outcomes of Bariatric Surgery in Siriraj Hospital for the First 100 Morbidly Obese Patients Treated

Objective: Bariatric surgery is considered the most effective treatment for morbid obesity, and is increasingly performed in Thailand and globally. We aimed to establish the outcomes of bariatric surgery performed at Siriraj Hospital, Bangkok. Materials and Methods: This was a retrospective study of patients who underwent bariatric surgery between January 2012 and June 2016. Results: The records of the first 100 patients who underwent bariatric surgery were reviewed, comprising 58 patients who underwent laparoscopic sleeve gastrectomy (LSG) and 42 patients who underwent laparoscopic Roux-en-Y gastric bypass (LRYGB). The median patient age, preoperative body weight, and BMI were 36 years old, 129 kg, and 46.3 kg/m2. All the procedures were performed by a laparoscopic approach. The median operative times for LSG and LRYGB were 156 [85-435] and 265 [180-435] minutes. The median hospital stay was 3 days [3-14]. The major complication rate was 4%. There was no mortality in the 30-day postoperative period. The mean %excess weight loss (%EWL) of LSG was 56.8 ± 19.8%, 59.9 ± 21.7%, and 55.1 ± 21.3%, at 1, 2, and 3 years after surgery. The mean %EWL of LRYGB was 67 ± 18.3%, 66.2 ± 21.4%, and 63.6 ± 19.9%, at 1, 2, and 3 years after surgery. In the patients with type-II diabetes mellitus, 67% had complete diabetic remission at 1 year. The median FBS dropped from 127 to 99 mg/dL (p < 0.001) and HbA1c from 6.6% to 5.5% (p < 0.001). The remission rates of hypertension and dyslipidemia were 58% and 73%. Conclusion: The bariatric procedures are safe with a low complication rate. The procedures also provide good outcomes in postoperative weight loss and comorbidity resolution

Catalytic Conversion of Guaiacol Catalyzed by Platinum Supported on Alumina: Reaction Network Including Hydrodeoxygenation Reactions

The conversion of guaiacol catalyzed by Pt/γ-Al₂O₃ in the presence of H₂ was investigated with a flow reactor at 573 K and 140 kPa. Dozens of reaction products were identified, with the most abundant being phenol, catechol, and 3-methylcatechol. The kinetically significant reaction classes were found to be hydrogenolysis [including hydrodeoxygenation (HDO)], hydrogenation, and transalkylation. Selectivity–conversion data were used to determine an approximate quantitative reaction network accounting for the primary products, and a more detailed qualitative network was also inferred. Catalytic HDO was evidenced by the production of anisole and phenol. The HDO selectivity increased with an increasing H₂ partial pressure and a decreasing temperature. Products formed by transalkylation reactions match those produced in the conversion catalyzed by HY zeolite, in which no deoxygenated products were observed

Outcomes of Single-Incision Laparoscopic Surgery for Colon Cancer: A Case-Matched Comparative Study

Background: Single-incisionlaparoscopiccolectomy(SILC) isanevolvingtechnique withpotentialadvantages by reducing number of incisions that can reduce port-related complications and improve cosmetic results. The purposeof thisstudy wastocomparetheshort-termoutcomesbetweenSILC,hand-assistedlaparoscopiccolectomy (HALC) andstandard multi-port laparoscopic colectomy (MLC). Methods: Retrospectiveanalysesofatotalof90patientsbetweenMay2010and December2011, whounderwent SILC for coloncancer surgery, wereperformedin30patients. Clinicopathologicalparameters were matched1:1 withpatients whounderwent HALC (n=30)andMLC (n=30).Short-term outcomes werecollectedandanalyzed. Results: Operativetime wassignificantlyshorter inSILC comparedto HALC andMLC (p<0.001),as wellasless estimatedbloodloss (p=0.02). There werenosignificantdifferences inconversionrateandnumberofharvested lymphnodes.SILChadtheadvantageofless24-hrpostoperativepainscorecomparedtoHALCandMLC(p<0.001), whereas length of stayandtime to full diet werenotdifferent. Conclusion: Inselectedpatients,SILC canbesuccessfullyandsafelyperformed withshorteroperativetime, less estimated blood loss andless postoperativepainscore